IMS Final Release

# IMS Question and Test Interoperability (QTI): Usage Data Information Model and XSD Binding Version 2.2

# IMS Final Release
Version 1.0.1

Date Issued: | 1st August, 2016
Latest version: | http://www.imsglobal.org/question/

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Document Name: IMS Question and Test Interoperability (QTI): Usage Data Information Model and XSD Binding v2.2

Revision: 1st August, 2016

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# Table of Contents

1. Introduction

1.1. Overview of QTI Usage Data Statistics

1.2. Scope and Context

1.3. Structure of this Document

1.4. Nomenclature

1.5. References

2. Information Model

2.1. Information Model Overview

2.2. Root Attribute Description

2.2.1 "usageData" Root Attribute Description

2.3. Root Class Description

2.3.1 "UsageData" Root Class Description

2.3.1.1 "glossary" Characteristic Description

2.3.1.2 "itemStatistic" Attribute Description

2.4. Data Class Descriptions

2.4.1 "CategorizedStatistic" Class Description

2.4.1.1 "name" Characteristic Description

2.4.1.2 "glossary" Characteristic Description

2.4.1.3 "context" Characteristic Description

2.4.1.4 "caseCount" Characteristic Description

2.4.1.5 "stdError" Characteristic Description

2.4.1.6 "stdDeviation" Characteristic Description

2.4.1.7 "lastUpdated" Characteristic Description

2.4.1.8 "targetObject" Attribute Description

2.4.1.9 "mapping" Attribute Description

2.4.2 "Mapping" Class Description

2.4.2.1 "lowerBound" Characteristic Description

2.4.2.2 "upperBound" Characteristic Description

2.4.2.3 "defaultValue" Characteristic Description

2.4.2.4 "mapEntry" Attribute Description

2.4.3 "OrdinaryStatistic" Class Description

2.4.3.1 "name" Characteristic Description

2.4.3.2 "glossary" Characteristic Description

2.4.3.3 "context" Characteristic Description

2.4.3.4 "caseCount" Characteristic Description

2.4.3.5 "stdError" Characteristic Description

2.4.3.6 "stdDeviation" Characteristic Description

2.4.3.7 "lastUpdated" Characteristic Description

2.4.3.8 "targetObject" Attribute Description

2.4.3.9 "value" Attribute Description

2.5. Abstract Class Descriptions

2.5.1 "ItemStatistic" Class Description

2.5.1.1 "ordinaryStatistic" Attribute Description

2.5.1.2 "categorizedStatistic" Attribute Description

2.6. Derived Class Descriptions

2.6.1 "Date" Class Description

2.6.1.1 "pattern" Attribute Description

2.6.2 "Identifier" Class Description

2.6.3 "MapEntry" Class Description

2.6.3.1 "mapKey" Characteristic Description

2.6.3.2 "mappedValue" Characteristic Description

2.6.3.3 "caseSensitive" Characteristic Description

2.6.4 "TargetObject" Class Description

2.6.4.1 "identifier" Characteristic Description

2.6.4.2 "partIdentifier" Characteristic Description

2.6.5 "Value" Class Description

2.6.5.1 "fieldIdentifier" Characteristic Description

2.6.5.2 "baseType" Characteristic Description

2.7. Enumerated Vocabulary Descriptions

2.7.1 "BaseType" Vocabulary Description

2.8. External Vocabularies

2.8.1 "Distractor Statistics" External Vocabulary

2.8.2 "Item Statistics" External Vocabulary

3. XSD Binding

3.1. XSD Binding Overview

3.2. UML to XML/XSD Mapping

3.2.1 Root Attribute UML/XSD Mapping

3.2.2 Root Class UML/XSD Mapping

3.2.2.1 UsageData Root Class Mapping

3.2.3 Class UML/XSD Mapping

3.2.3.1 CategorizedStatistic Class Mapping

3.2.3.2 Mapping Class Mapping

3.2.3.3 OrdinaryStatistic Class Mapping

3.2.4 Derived Class UML/XSD Mapping

3.2.4.1 Date Class Mapping

3.2.4.2 Identifier Class Mapping

3.2.4.3 MapEntry Class Mapping

3.2.4.4 TargetObject Class Mapping

3.2.4.5 Value Class Mapping

3.2.5 Enumerated Class UML/XSD Mapping

3.2.6 Enumerated List Class UML/XSD Mapping

3.2.7 List Class UML/XSD Mapping

3.2.8 Union Class UML/XSD Mapping

3.2.9 Primitive Type UML/XSD Mapping

3.3. Filenames and Namespaces

3.3.1 Target Namespace Details

3.3.2 Imported Namespace Details

3.3.3 Implicit Namespace Details

3.4. Description of the XSD

3.4.1 Root Element Descriptions

3.4.1.1 "usageData" Root Element Description

3.4.2 Global Element Descriptions

3.4.3 Attribute Group Descriptions

3.4.4 Root Complex Type Descriptions

3.4.4.1 UsageData.Type Root Complex Type Description

* "glossary" Local Attribute Description

* "ordinaryStatistic" Local Element Description

* "categorizedStatistic" Local Element Description

3.4.5 Core Complex Type Descriptions

3.4.5.1 CategorizedStatistic.Type Core Complex Type Description

* "name" Local Attribute Description

* "glossary" Local Attribute Description

* "context" Local Attribute Description

* "caseCount" Local Attribute Description

* "stdError" Local Attribute Description

* "stdDeviation" Local Attribute Description

* "lastUpdated" Local Attribute Description

* "targetObject" Local Element Description

* "mapping" Local Element Description

3.4.5.2 Mapping.Type Core Complex Type Description

* "lowerBound" Local Attribute Description

* "upperBound" Local Attribute Description

* "defaultValue" Local Attribute Description

* "mapEntry" Local Element Description

3.4.5.3 OrdinaryStatistic.Type Core Complex Type Description

* "name" Local Attribute Description

* "glossary" Local Attribute Description

* "context" Local Attribute Description

* "caseCount" Local Attribute Description

* "stdError" Local Attribute Description

* "stdDeviation" Local Attribute Description

* "lastUpdated" Local Attribute Description

* "targetObject" Local Element Description

* "value" Local Element Description

3.4.6 Derived Complex Type Descriptions

3.4.6.1 MapEntry.Type Derived Complex Type Description

* "mapKey" Local Attribute Description

* "mappedValue" Local Attribute Description

* "caseSensitive" Local Attribute Description

3.4.6.2 TargetObject.Type Derived Complex Type Description

* "identifier" Local Attribute Description

* "partIdentifier" Local Attribute Description

3.4.6.3 Value.Type Derived Complex Type Description

* "fieldIdentifier" Local Attribute Description

* "baseType" Local Attribute Description

3.4.7 Simple Type Descriptions

3.4.7.1 Date.Type Simple Type Description

3.4.7.2 Identifier.Type Simple Type Description

3.5. The Schematron Rules

3.6. The VDEX Vocabulary Bindings

3.6.1 "Distractor Statistics" Vocabulary VDEX Binding Description

3.6.2 "Item Statistics" Vocabulary VDEX Binding Description

4. Extending and Profiling the Data Model

4.1. Extending the Data Model

4.2. Profiling the Data Model

Appendix A Modelling Concepts and Terms

A1 Data Model Descriptions

A1.1 Data Model Diagrams

A1.2 Class Descriptions

A1.3 Attribute and Characteristic Descriptions

A1.4 Enumerated Vocabulary Descriptions

A1.5 External Vocabulary Descriptions

A1.6 Import Class Descriptions

Appendix B XSD Binding Terms

B1 XSD Binding Description Terms

B1.1 UML/XSD Attribute Mapping Table Definition

B1.2 UML/XSD Class Mapping Table Definition

B1.3 UML/XSD Enumerated and Enumerated List Class Mapping Table Definition

B1.4 UML/XSD List and Union Mapping Tables Definition

B1.5 UML/XSD Primitive Types Mapping Table Definition

B1.6 XSD Description for an Element

B1.7 XSD Description for a Complex Type

B1.8 XSD Description for a Simple Type

B1.9 XSD Description for an Attribute Group

B1.10 XSD Description for an Attribute

B1.11 VDEX Description for an External Vocabulary

Appendix C XSD Listings

C1 QTI Usage Data Statistics XSD Listing

Appendix D VDEX Listings

Appendix D1 "Distractor Statistics" Vocabulary Listing

Appendix D2 "Item Statistics" Vocabulary Listing

About this Document

List of Contributors

Revision History

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# List of Figures

Figure 2.3.1 UsageData class definitions

Figure 2.4.1 CategorizedStatistic class definitions

Figure 2.4.2 Mapping class definitions

Figure 2.4.3 OrdinaryStatistic class definitions

Figure 2.5.1 ItemStatistic class definitions

Figure 2.6.1 Date class definitions

Figure 2.6.2 Identifier class definitions

Figure 2.6.3 MapEntry class definitions

Figure 2.6.4 TargetObject class definitions

Figure 2.6.5 Value class definitions

Figure 2.7.1 BaseType class definitions

Figure 3.4.1.1 XSD Description for the "usageData" Root Element

Figure 3.4.4.1 XSD Description for the "UsageData.Type" Root ComplexType

Figure XSD Description for the "glossary" Local Attribute

Figure XSD Description for the "ordinaryStatistic" Local Element Description

Figure XSD Description for the "categorizedStatistic" Local Element Description

Figure 3.4.5.1 XSD Description for the "CategorizedStatistic.Type" Core Complex Type

Figure XSD Description for the "name" Local Attribute

Figure XSD Description for the "glossary" Local Attribute

Figure XSD Description for the "context" Local Attribute

Figure XSD Description for the "caseCount" Local Attribute

Figure XSD Description for the "stdError" Local Attribute

Figure XSD Description for the "stdDeviation" Local Attribute

Figure XSD Description for the "lastUpdated" Local Attribute

Figure XSD Description for the "targetObject" Local Element

Figure XSD Description for the "mapping" Local Element

Figure 3.4.5.2 XSD Description for the "Mapping.Type" Core Complex Type

Figure XSD Description for the "lowerBound" Local Attribute

Figure XSD Description for the "upperBound" Local Attribute

Figure XSD Description for the "defaultValue" Local Attribute

Figure XSD Description for the "mapEntry" Local Element

Figure 3.4.5.3 XSD Description for the "OrdinaryStatistic.Type" Core Complex Type

Figure XSD Description for the "name" Local Attribute

Figure XSD Description for the "glossary" Local Attribute

Figure XSD Description for the "context" Local Attribute

Figure XSD Description for the "caseCount" Local Attribute

Figure XSD Description for the "stdError" Local Attribute

Figure XSD Description for the "stdDeviation" Local Attribute

Figure XSD Description for the "lastUpdated" Local Attribute

Figure XSD Description for the "targetObject" Local Element

Figure XSD Description for the "value" Local Element

Figure 3.4.6.1 XSD Description for the "MapEntry.Type" Derived Complex Type

Figure XSD Description for the "mapKey" Local Attribute

Figure XSD Description for the "mappedValue" Local Attribute

Figure XSD Description for the "caseSensitive" Local Attribute

Figure 3.4.6.2 XSD Description for the "TargetObject.Type" Derived Complex Type

Figure XSD Description for the "identifier" Local Attribute

Figure XSD Description for the "partIdentifier" Local Attribute

Figure 3.4.6.3 XSD Description for the "Value.Type" Derived Complex Type

Figure XSD Description for the "fieldIdentifier" Local Attribute

Figure XSD Description for the "baseType" Local Attribute

Figure 3.4.7.1 XSD Description for the "Date.Type" Simple Type

Figure 3.4.7.2 XSD Description for the "Identifier.Type" Simple Type

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# List of Tables

Table 2.2.1 "usageData" root attribute description

Table 2.3.1 UsageData class definitions

Table 2.3.1.1 Description of the "glossary" characteristic for the "UsageData" class

Table 2.3.1.2 Description of the "itemStatistic" attribute for the "UsageData" class

Table 2.4.1 CategorizedStatistic class definitions

Table 2.4.1.1 Description of the "name" characteristic for the "CategorizedStatistic" class

Table 2.4.1.2 Description of the "glossary" characteristic for the "CategorizedStatistic" class

Table 2.4.1.3 Description of the "context" characteristic for the "CategorizedStatistic" class

Table 2.4.1.4 Description of the "caseCount" characteristic for the "CategorizedStatistic" class

Table 2.4.1.5 Description of the "stdError" characteristic for the "CategorizedStatistic" class

Table 2.4.1.6 Description of the "stdDeviation" characteristic for the "CategorizedStatistic" class

Table 2.4.1.7 Description of the "lastUpdated" characteristic for the "CategorizedStatistic" class

Table 2.4.1.8 Description of the "targetObject" attribute for the "CategorizedStatistic" class

Table 2.4.1.9 Description of the "mapping" attribute for the "CategorizedStatistic" class

Table 2.4.2 Mapping class definitions

Table 2.4.2.1 Description of the "lowerBound" characteristic for the "Mapping" class

Table 2.4.2.2 Description of the "upperBound" characteristic for the "Mapping" class

Table 2.4.2.3 Description of the "defaultValue" characteristic for the "Mapping" class

Table 2.4.2.4 Description of the "mapEntry" attribute for the "Mapping" class

Table 2.4.3 OrdinaryStatistic class definitions

Table 2.4.3.1 Description of the "name" characteristic for the "OrdinaryStatistic" class

Table 2.4.3.2 Description of the "glossary" characteristic for the "OrdinaryStatistic" class

Table 2.4.3.3 Description of the "context" characteristic for the "OrdinaryStatistic" class

Table 2.4.3.4 Description of the "caseCount" characteristic for the "OrdinaryStatistic" class

Table 2.4.3.5 Description of the "stdError" characteristic for the "OrdinaryStatistic" class

Table 2.4.3.6 Description of the "stdDeviation" characteristic for the "OrdinaryStatistic" class

Table 2.4.3.7 Description of the "lastUpdated" characteristic for the "OrdinaryStatistic" class

Table 2.4.3.8 Description of the "targetObject" attribute for the "OrdinaryStatistic" class

Table 2.4.3.9 Description of the "value" attribute for the "OrdinaryStatistic" class

Table 2.5.1 ItemStatistic class definitions

Table 2.5.1.1 Description of the "ordinaryStatistic" attribute for the "ItemStatistic" class

Table 2.5.1.2 Description of the "categorizedStatistic" attribute for the "ItemStatistic" class

Table 2.6.1 Date class definitions

Table 2.6.1.1 Description of the "pattern" attribute for the "Date" class

Table 2.6.2 Identifier class definitions

Table 2.6.3 MapEntry class definitions

Table 2.6.3.1 Description of the "mapKey" characteristic for the "MapEntry" class

Table 2.6.3.2 Description of the "mappedValue" characteristic for the "MapEntry" class

Table 2.6.3.3 Description of the "caseSensitive" characteristic for the "MapEntry" class

Table 2.6.4 TargetObject class definitions

Table 2.6.4.1 Description of the "identifier" characteristic for the "TargetObject" class

Table 2.6.4.2 Description of the "partIdentifier" characteristic for the "TargetObject" class

Table 2.6.5 Value class definitions

Table 2.6.5.1 Description of the "fieldIdentifier" characteristic for the "Value" class

Table 2.6.5.2 Description of the "baseType" characteristic for the "Value" class

Table 2.7.1 BaseType class definitions

Table 2.8.1 Distractor Statistics external vocabulary definition

Table 2.8.2 Item Statistics external vocabulary definition

Table 3.2.1 UML/XSD Mapping for the Root Attributes

Table 3.2.2.1 UML/XSD Mapping for the UsageData Root Class

Table 3.2.3.1 UML/XSD Mapping for the CategorizedStatistic Core Class

Table 3.2.3.2 UML/XSD Mapping for the Mapping Core Class

Table 3.2.3.3 UML/XSD Mapping for the OrdinaryStatistic Core Class

Table 3.2.4.1 UML/XSD Mapping for the Date Derived Class

Table 3.2.4.2 UML/XSD Mapping for the Identifier Derived Class

Table 3.2.4.3 UML/XSD Mapping for the MapEntry Derived Class

Table 3.2.4.4 UML/XSD Mapping for the TargetObject Derived Class

Table 3.2.4.5 UML/XSD Mapping for the Value Derived Class

Table 3.2.5 UML/XSD Mapping for the Enumerated Class Definitions

Table 3.2.9 UML/XSD Mapping for the Primitive Type Definitions

Table 3.4.1.1 XSD Description for the "usageData" Root Element

Table 3.4.4.1 XSD Description for the "UsageData.Type" Root ComplexType

Table XSD Description for the "glossary" Local Attribute

Table XSD Description for the "ordinaryStatistic" Local Element Description

Table XSD Description for the "categorizedStatistic" Local Element Description

Table 3.4.5.1 XSD Description for the "CategorizedStatistic.Type" Core Complex Type

Table XSD Description for the "name" Local Attribute

Table XSD Description for the "glossary" Local Attribute

Table XSD Description for the "context" Local Attribute

Table XSD Description for the "caseCount" Local Attribute

Table XSD Description for the "stdError" Local Attribute

Table XSD Description for the "stdDeviation" Local Attribute

Table XSD Description for the "lastUpdated" Local Attribute

Table XSD Description for the "targetObject" Local Element

Table XSD Description for the "mapping" Local Element

Table 3.4.5.2 XSD Description for the "Mapping.Type" Core Complex Type

Table XSD Description for the "lowerBound" Local Attribute

Table XSD Description for the "upperBound" Local Attribute

Table XSD Description for the "defaultValue" Local Attribute

Table XSD Description for the "mapEntry" Local Element

Table 3.4.5.3 XSD Description for the "OrdinaryStatistic.Type" Core Complex Type

Table XSD Description for the "name" Local Attribute

Table XSD Description for the "glossary" Local Attribute

Table XSD Description for the "context" Local Attribute

Table XSD Description for the "caseCount" Local Attribute

Table XSD Description for the "stdError" Local Attribute

Table XSD Description for the "stdDeviation" Local Attribute

Table XSD Description for the "lastUpdated" Local Attribute

Table XSD Description for the "targetObject" Local Element

Table XSD Description for the "value" Local Element

Table 3.4.6.1 XSD Description for the "MapEntry.Type" Derived Complex Type

Table XSD Description for the "mapKey" Local Attribute

Table XSD Description for the "mappedValue" Local Attribute

Table XSD Description for the "caseSensitive" Local Attribute

Table 3.4.6.2 XSD Description for the "TargetObject.Type" Derived Complex Type

Table XSD Description for the "identifier" Local Attribute

Table XSD Description for the "partIdentifier" Local Attribute

Table 3.4.6.3 XSD Description for the "Value.Type" Derived Complex Type

Table XSD Description for the "fieldIdentifier" Local Attribute

Table XSD Description for the "baseType" Local Attribute

Table 3.4.7.1 XSD Description for the "Date.Type" Simple Type

Table 3.4.7.2 XSD Description for the "Identifier.Type" Simple Type

Table 3.6.1 VDEX Description for the "Distractor Statistics" Vocabulary.

Table 3.6.2 VDEX Description for the "Item Statistics" Vocabulary.

Table A1.1 The key to the descriptions of data model diagrams

Table A1.2 The key to the descriptions of the data class tables

Table A1.3 The key to the descriptions of the data attribute/characteristic tables

Table A1.4 The key to the descriptions of the enumerated vocabulary tables

Table A1.5 The key to the descriptions of the external vocabulary tables

Table A1.6 The key to the descriptions of the import class tables

Table B1.1 The key to the descriptions of UML to XSD attribute mapping tables

Table B1.2 The key to the descriptions of UML to XSD class mapping tables

Table B1.3 The key to the descriptions of UML to XSD enumerated and enumerated list class mapping tables

Table B1.4 The key to the descriptions of UML to XSD list class mapping table

Table B1.5 The key to the descriptions of UML to XSD primitive mapping table

Table B1.6 The key to the descriptions of XSD element tables

Table B1.7 The key to the descriptions of XSD complex type tables

Table B1.8 The key to the descriptions of XSD simple type tables

Table B1.9 The key to the descriptions of XSD attribute group tables

Table B1.10 The key to the descriptions of XSD attribute tables

Table B1.11 The key to the descriptions of VDEX vocabulary binding tables

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# 1. Introduction

## 1.1. Overview of QTI Usage Data Statistics

This document is a part of the IMS Global Question and Test Interoperability (QTI) v2.2 specification. It introduces QTI Usage Data for reporting statistical information about the usage of a set of items. While the expectation is that the original definition of the corresponding Items is based upon the use of the QTIv2.2 Assessment, Section and Item specification [QTI, 16a], this is not a pre-requisite for the use of this usage data representation.

## 1.2. Scope and Context

The IMS QTI Usage Data v2.2 is used in conjunction with the following documents:

- IMS Question and Test Interoperability: Assessment, Section and Item (ASI) Information Model v2.2 [QTI, 16a] - the data model definition for the exchange of Assessments, Sections and Items;
- IMS Question and Test Interoperability v2.2 Best Practice and Implementation Guide v1.0 [QTI, 15b] - key information on how to adopt and implement the specification.

This QTI Usage Data v2.2 specification supersedes the QTI v2.1 versions. There have been no functional changes and only the namespace and schema location of the XSD have been altered. The QTI Information Model is bound to an XML Schema Definition (XSD) and the external vocabularies supplied as Vocabulary Definition and Exchange (VDEX) instances [VDEX, 04]. This document and the accompanying XSD is generated using the IMS Global Binding Auto-generation Tool-kit (I-BAT) [I-BAT, 06].

## 1.3. Structure of this Document

The structure of the rest of this document is:

2. Information Model | The Information Model description for the QTI Usgae Data. This description uses a profile of UML to represent the structure of the data model;
3. XSD Binding | This is the description of the binding of the data model to XML and the corresponding XSD that is used to validate QTI Usage Data instances. This description includes an explanation of the relationship between the UML representation and the XSD that is produced through transformation of that representation;
4. Extending and Profiling the Data Model | Identification of the ways in which the data model can be extended (both in terms of the extending features and proprietary extensions to the model) and how this base specification, and its model-based description, can be profiled to produce derivative specifications;
Appendix A Modelling Concepts and Terms | An overview of the model driven approach, the concepts and the terms used by IMS to create the data model representations (based upon a profile of UML), the corresponding set of bindings and the accompanying documentation (including this information model);
Appendix B XSD Binding Terms | An overview of the concepts and the terms used by IMS to create theXSD-based bindings representations and the accompanying documentation. The XSD binding is auto-generated from the UML representation to ensure full consistency between the information model and binding;
Appendix C XSD Listings | The listing of the QTI Usage Data XSD that should be used to validate instances of the data exchange;
Appendix D VDEX Listings | The listings of the VDEX XML binding files that contain the external vocabularies instances. Each of these XML files is an instance of the IMS VDEX specification.

## 1.4. Nomenclature

AIS | Average Item Score
ASI | Assessment, Section, Item
DT | Derived Type
I-BAT | IMS Binding Autogeneration Toolkit
IRT | Item Response Theory
ISO | International Standards Organization
PT | Primitive Type
QTI | Question and Test Interoperability
RFC | Request For Comment
UML | Unified Modeling Language
URI | Uniform Resource Identifier
VDEX | Vocabulary Definition Exchange
W3C | World Wide Web Consortium
XML | Exchange Markup Language
XOR | Exclusive OR
XSD | XML Schema Definition

## 1.5. References

[I-BAT, 06] | IMS Binding Auto-generation Toolkit (I-BAT), Colin Smythe, IMS Global Learning Consortium Inc., July 2006.
[ISO 8601] | ISO8601:2004 Data elements and interchange formats - Information interchange - Representation of dates and times, ISO, International Standards Organization (ISO), 2000, p.33.
[QTI, 15b] | IMS Question and Test Interoperability (QTI): Best Practices and Implementation Guide v2.2, Tom Hoffmann and Wilbert Kraan, IMS Global Learning Consortium Inc., September 2015, http://www.imsglobal.org/question/qtiv2p2/imsqti_v2p2_impl.html.
[QTI, 16a] | IMS Question and Test Interoperability (QTI): Assessment, Section and Item (ASI) Information Model v2.2.1, Colin Smythe, Wilbert Kraan and Mark McKell, IMS Global Learning Consortium Inc., August 2016, http://www.imsglobal.org/question/qtiv2p2/QTIv2p2p1-ASI-InformationModelv1p0/imsqtiv2p2p1_asi_v1p0_InfoModelv1p0.html.
[RFC 2045] | Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies, N. Freed and N. Borenstein, Internet Engineering Task Force, November, 1996, https://www.ietf.org/rfc/rfc2045.txt.
[URI, 98] | Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies, T. Berners-Lee, R. Fielding and L. Masinter, Internet Engineering Task Force, August 1998, https://www.ietf.org/rfc/rfc2396.txt.
[VDEX, 04] | IMS Vocabulary Definition Exchange Information Model v1.0, Adam Cooper, IMS Global Learning Consortium Inc., February 2004, http://www.imsglobal.org/vdex/vdexv1p0/imsvdex_infov1p0.html.
[XML, 00] | Extensible Markup Language (XML), Version 1.0 (second edition), Tim Bray, Jean Paoli, C. M. Sperberg-McQueen and Eve Maler, World Wide Web Consortium, October 2000, http://www.w3.org/TR/2000/REC-xml-20001006.

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# 2. Information Model

## 2.1. Information Model Overview

The Information Model is described using a UML representation approach. The description consists of:

- Root Attributes - the root object that contains the QTI Usage Data structure;
- Root Classes - the root class that defines the QTI Usage Data structure;
- Data Classes - the core data class that define the QTI Usage Data structure;
- Abstract Classes - the abstract classes that define the QTI Usage Data structure;
- Derived Classes - the classes in the data model that are derived from the primitive types or other derived types;
- Enumerated Classes - the classes that contain the intrinsic enumerated vocabularies;
- External Vocabularies - the enumerated external vocabularies i.e. to be contained in their own vocabulary instance file.

## 2.2. Root Attribute Description

All of the Root attributes (the root name for the instances that can be exchanged) used within this Information Model are described in this Section. The syntax and semantics for this representation is described in Appendix A1.3. The root attributes are:

- usageData - this is the Root attribute and as such is the top-level name for an instance of a 'UsageData' object. This is data model for the item usage statistics about an 'assessmentItem'.

### 2.2.1 "usageData" Root Attribute Description

The definition of the "usageData" root attribute is shown in Table 2.2.1.

Table 2.2.1 Description of the "usageData" root attribute.
Descriptor | Definition
--- | ---
Attribute Name | usageData
Data Type | UsageData
Description | This is the Root attribute and as such is the top-level name for an instance of a 'UsageData' object. This is data model for the item usage statistics about an 'assessmentItem'.

## 2.3. Root Class Description

All of the Root data classes (the first class objects that can be exchanged using the data model) used within this Information Model are described in this Section. The syntax and semantics for this representation is described in Appendix A1.2.

### 2.3.1 UsageData Root Class Description

The data model for the "UsageData" root class is shown in Figure 2.3.1 and the accompanying definition in Table 2.3.1.

Figure 2.3.1 - UsageData class definitions.

Table 2.3.1 Description of the "UsageData" class.
Descriptor | Definition
--- | ---
Class Name | UsageData
Class Type | Container [ Sequence ]
Parents | None (Root Class)
Derived Classes | There are no derived classes.
Super Classes | This class is not derived from another class.
Characteristics | The set of characteristics are: glossary
Children | The set of children attributes are: itemStatistic
Description | Usage data, most commonly item statistics, do not form part of an assessmentItem directly because they always relate to some context or domain in which the statistics are valid. Therefore, this specification defines a separate class for describing these statistics. Each statistic refers to both its context and to the assessmentItem(s) it relates to. Therefore, instances of this class are bound and packaged separately for interoperability.

#### 2.3.1.1 "glossary" Characteristic Description

The description of the "glossary" characteristic for the "UsageData" root class is given in Table 2.3.1.1

Table 2.3.1.1 Description of the "glossary" characteristic for the "UsageData" class.
Descriptor | Definition
--- | ---
Characteristic Name | glossary
Data Type | AnyURI (Primitive-type)
Value Space | See Appendix A1.3.
Scope | Local ("-")
Multiplicity | [0..1]
Description | An optional URI that identifies the default glossary in which the names of the itemStatistics are defined. This URI should refer to the corresponding VDEX Vocabulary Identifier.

#### 2.3.1.2 "itemStatistic" Attribute Description

The description of the "itemStatistic" attribute for the "UsageData" root class is given in Table 2.3.1.2.

Table 2.3.1.2 Description of the "itemStatistic" attribute for the "UsageData" root class.
Descriptor | Definition
--- | ---
Attribute Name | itemStatistic
Data Type | ItemStatistic
Value Space | Abstract Container [ Selection ]
Scope | Local ("-")
Multiplicity | [0.. unbounded]
Description | A value or set of values that describe the performance of the item within a specific context. Common measures include the item's difficulty and how well it discriminates between various candidate ability levels. This is an abstract attribute and so a feature named 'itemStatistic' will not appear in an instance. Instead, it enables the construction of a more complex 'UsageData' class based upon the multiple selections of the children of the 'ItemStatistic' class.

## 2.4. Data Class Descriptions

All of the data classes used within this Information Model are described in this Section. The syntax and semantics for this representation is described in Appendix A1.2.

### 2.4.1 CategorizedStatistic Class Description

The data model for the "CategorizedStatistic" class is shown in Figure 2.4.1 and the accompanying definition in Table 2.4.1.

Figure 2.4.1 - CategorizedStatistic class definitions.

Table 2.4.1 Description of the "CategorizedStatistic" class.
Descriptor | Definition
--- | ---
Class Name | CategorizedStatistic
Class Type | Container [ Sequence ]
Parents | The set of parent classes are: ItemStatistic
Derived Classes | There are no derived classes.
Super Classes | This class is not derived from another class.
Characteristics | The set of characteristics are: name glossary context caseCount stdError stdDeviation lastUpdated
Children | The set of children attributes are: targetObject mapping
Description | An item statistic that consists of multiple values, e.g. IRT Dispersion Parameters.

#### 2.4.1.1 "name" Characteristic Description

The description of the "name" characteristic for the "CategorizedStatistic" class is given in Table 2.4.1.1.

Table 2.4.1.1 Description of the "name" characteristic for the "CategorizedStatistic" class.
Descriptor | Definition
--- | ---
Characteristic Name | name
Data Type | Identifier
Value Space | Container [ DerivedType ]
Scope | Local ("-")
Multiplicity | [1]
Description | The unique identifier of the item statistic. Glossaries of identifiers defined by this specification for commonly used item and distractor statistics are defined and should be used where possible. See Vocabulary for the Exchange of Item Statistics for more details.

#### 2.4.1.2 "glossary" Characteristic Description

The description of the "glossary" characteristic for the "CategorizedStatistic" class is given in Table 2.4.1.2.

Table 2.4.1.2 Description of the "glossary" characteristic for the "CategorizedStatistic" class.
Descriptor | Definition
--- | ---
Characteristic Name | glossary
Data Type | AnyURI (Primitive-type)
Value Space | See Appendix A1.3.
Scope | Local ("-")
Multiplicity | [0..1]
Description | An optional URI that identifies the glossary in which the name is defined. This value overrides any default glossary provided by the glossary attribute of the parent usageData.

#### 2.4.1.3 "context" Characteristic Description

The description of the "context" characteristic for the "CategorizedStatistic" class is given in Table 2.4.1.3.

Table 2.4.1.3 Description of the "context" characteristic for the "CategorizedStatistic" class.
Descriptor | Definition
--- | ---
Characteristic Name | context
Data Type | AnyURI (Primitive-type)
Value Space | See Appendix A1.3.
Scope | Local ("-")
Multiplicity | [1]
Description | A Uniform Resource Identifier that points to information about the context within which the item statistic was created. For example, the URI may point to the sample of item scores and the specifics of computations that created item statistics. The URI may be a URL, a database index, or other valid identifier

#### 2.4.1.4 "caseCount" Characteristic Description

The description of the "caseCount" characteristic for the "CategorizedStatistic" class is given in Table 2.4.1.4.

Table 2.4.1.4 Description of the "caseCount" characteristic for the "CategorizedStatistic" class.
Descriptor | Definition
--- | ---
Characteristic Name | caseCount
Data Type | Integer (Primitive-type)
Value Space | See Appendix A1.3.
Scope | Local ("-")
Multiplicity | [0..1]
Description | The number of cases in the sample used to create the item statistic.

#### 2.4.1.5 "stdError" Characteristic Description

The description of the "stdError" characteristic for the "CategorizedStatistic" class is given in Table 2.4.1.5.

Table 2.4.1.5 Description of the "stdError" characteristic for the "CategorizedStatistic" class.
Descriptor | Definition
--- | ---
Characteristic Name | stdError
Data Type | Double (Primitive-type)
Value Space | See Appendix A1.3.
Scope | Local ("-")
Multiplicity | [0..1]
Description | The standard error of the item statistic, also known as the variance.

#### 2.4.1.6 "stdDeviation" Characteristic Description

The description of the "stdDeviation" characteristic for the "CategorizedStatistic" class is given in Table 2.4.1.6.

Table 2.4.1.6 Description of the "stdDeviation" characteristic for the "CategorizedStatistic" class.
Descriptor | Definition
--- | ---
Characteristic Name | stdDeviation
Data Type | Double (Primitive-type)
Value Space | See Appendix A1.3.
Scope | Local ("-")
Multiplicity | [0..1]
Description | The standard deviation of the item statistic (i.e. the square root of the standard error).

#### 2.4.1.7 "lastUpdated" Characteristic Description

The description of the "lastUpdated" characteristic for the "CategorizedStatistic" class is given in Table 2.4.1.7.

Table 2.4.1.7 Description of the "lastUpdated" characteristic for the "CategorizedStatistic" class.
Descriptor | Definition
--- | ---
Characteristic Name | lastUpdated
Data Type | Date
Value Space | Container [ DerivedType ]
Scope | Local ("-")
Multiplicity | [0..1]
Description | Date of the last update to the item statistic value.

#### 2.4.1.8 "targetObject" Attribute Description

The description of the "targetObject" attribute for the "CategorizedStatistic" class is given in Table 2.4.1.8.

Table 2.4.1.8 Description of the "targetObject" attribute for the "CategorizedStatistic" class.
Descriptor | Definition
--- | ---
Attribute Name | targetObject
Data Type | TargetObject
Value Space | Container [ DerivedType ]
Scope | Local ("-")
Multiplicity | [1.. unbounded]
Description | The targetObject is used to refer to an assessment object. This object may be an assessmentItem or some other type of object defined outside the scope of this specification, for example, an entire test. In some cases it is desirable to refer not just to the assessment object but to a specific part of that object, in which case the optional partIdentifier can be used.

#### 2.4.1.9 "mapping" Attribute Description

The description of the "mapping" attribute for the "CategorizedStatistic" class is given in Table 2.4.1.9.

Table 2.4.1.9 Description of the "mapping" attribute for the "CategorizedStatistic" class.
Descriptor | Definition
--- | ---
Attribute Name | mapping
Data Type | Mapping
Value Space | Container [ Sequence ]
Scope | Local ("-")
Multiplicity | [1]
Description | The mapping from a source set of any baseType (except file and duration) to a single float. Note that mappings from values of base type float should be avoided due to the difficulty of matching floating point values, see the match operator for more details.

### 2.4.2 Mapping Class Description

The data model for the "Mapping" class is shown in Figure 2.4.2 and the accompanying definition in Table 2.4.2.

Figure 2.4.2 - Mapping class definitions.

Table 2.4.2 Description of the "Mapping" class.
Descriptor | Definition
--- | ---
Class Name | Mapping
Class Type | Container [ Sequence ]
Parents | The set of parent classes are: CategorizedStatistic
Derived Classes | There are no derived classes.
Super Classes | This class is not derived from another class.
Characteristics | The set of characteristics are: lowerBound upperBound defaultValue
Children | The set of children attributes are: mapEntry
Description | A special class used to create a mapping from a source set of any baseType (except file and duration) to a single float. Note that mappings from values of base type float should be avoided due to the difficulty of matching floating point values, see the match operator for more details. When mapping containers the result is the sum of the mapped values from the target set. See mapResponse for details.

#### 2.4.2.1 "lowerBound" Characteristic Description

The description of the "lowerBound" characteristic for the "Mapping" class is given in Table 2.4.2.1.

Table 2.4.2.1 Description of the "lowerBound" characteristic for the "Mapping" class.
Descriptor | Definition
--- | ---
Characteristic Name | lowerBound
Data Type | Double (Primitive-type)
Value Space | See Appendix A1.3.
Scope | Local ("-")
Multiplicity | [0..1]
Description | The lower bound for the result of mapping a container. If unspecified there is no lower-bound.

#### 2.4.2.2 "upperBound" Characteristic Description

The description of the "upperBound" characteristic for the "Mapping" class is given in Table 2.4.2.2.

Table 2.4.2.2 Description of the "upperBound" characteristic for the "Mapping" class.
Descriptor | Definition
--- | ---
Characteristic Name | upperBound
Data Type | Double (Primitive-type)
Value Space | See Appendix A1.3.
Scope | Local ("-")
Multiplicity | [0..1]
Description | The upper bound for the result of mapping a container. If unspecified there is no upper-bound.

#### 2.4.2.3 "defaultValue" Characteristic Description

The description of the "defaultValue" characteristic for the "Mapping" class is given in Table 2.4.2.3.

Table 2.4.2.3 Description of the "defaultValue" characteristic for the "Mapping" class.
Descriptor | Definition
--- | ---
Characteristic Name | defaultValue
Data Type | Double (Primitive-type)
Value Space | See Appendix A1.3. Default = "0".
Scope | Local ("-")
Multiplicity | [0..1]
Description | The default value from the target set to be used when no explicit mapping for a source value is given.

#### 2.4.2.4 "mapEntry" Attribute Description

The description of the "mapEntry" attribute for the "Mapping" class is given in Table 2.4.2.4.

Table 2.4.2.4 Description of the "mapEntry" attribute for the "Mapping" class.
Descriptor | Definition
--- | ---
Attribute Name | mapEntry
Data Type | MapEntry
Value Space | Container [ DerivedType ]
Scope | Local ("-")
Multiplicity | [1.. unbounded]
Description | The map is defined by a set of mapEntries, each of which maps a single value from the source set onto a single float.

### 2.4.3 OrdinaryStatistic Class Description

The data model for the "OrdinaryStatistic" class is shown in Figure 2.4.3 and the accompanying definition in Table 2.4.3.

Figure 2.4.3 - OrdinaryStatistic class definitions.

Table 2.4.3 Description of the "OrdinaryStatistic" class.
Descriptor | Definition
--- | ---
Class Name | OrdinaryStatistic
Class Type | Container [ Sequence ]
Parents | The set of parent classes are: ItemStatistic
Derived Classes | There are no derived classes.
Super Classes | This class is not derived from another class.
Characteristics | The set of characteristics are: name glossary context caseCount stdError stdDeviation lastUpdated
Children | The set of children attributes are: targetObject value
Description | An item statistic that consists of a single numeric value.

#### 2.4.3.1 "name" Characteristic Description

The description of the "name" characteristic for the "OrdinaryStatistic" class is given in Table 2.4.3.1.

Table 2.4.3.1 Description of the "name" characteristic for the "OrdinaryStatistic" class.
Descriptor | Definition
--- | ---
Characteristic Name | name
Data Type | Identifier
Value Space | Container [ DerivedType ]
Scope | Local ("-")
Multiplicity | [1]
Description | The unique identifier of the item statistic. Glossaries of identifiers defined by this specification for commonly used item and distractor statistics are defined and should be used where possible. See Vocabulary for the Exchange of Item Statistics for more details.

#### 2.4.3.2 "glossary" Characteristic Description

The description of the "glossary" characteristic for the "OrdinaryStatistic" class is given in Table 2.4.3.2.

Table 2.4.3.2 Description of the "glossary" characteristic for the "OrdinaryStatistic" class.
Descriptor | Definition
--- | ---
Characteristic Name | glossary
Data Type | AnyURI (Primitive-type)
Value Space | See Appendix A1.3.
Scope | Local ("-")
Multiplicity | [0..1]
Description | An optional URI that identifies the glossary in which the name is defined. This value overrides any default glossary provided by the glossary attribute of the parent usageData.

#### 2.4.3.3 "context" Characteristic Description

The description of the "context" characteristic for the "OrdinaryStatistic" class is given in Table 2.4.3.3.

Table 2.4.3.3 Description of the "context" characteristic for the "OrdinaryStatistic" class.
Descriptor | Definition
--- | ---
Characteristic Name | context
Data Type | AnyURI (Primitive-type)
Value Space | See Appendix A1.3.
Scope | Local ("-")
Multiplicity | [1]
Description | A Uniform Resource Identifier that points to information about the context within which the item statistic was created. For example, the URI may point to the sample of item scores and the specifics of computations that created item statistics. The URI may be a URL, a database index, or other valid identifier

#### 2.4.3.4 "caseCount" Characteristic Description

The description of the "caseCount" characteristic for the "OrdinaryStatistic" class is given in Table 2.4.3.4.

Table 2.4.3.4 Description of the "caseCount" characteristic for the "OrdinaryStatistic" class.
Descriptor | Definition
--- | ---
Characteristic Name | caseCount
Data Type | Integer (Primitive-type)
Value Space | See Appendix A1.3.
Scope | Local ("-")
Multiplicity | [0..1]
Description | The number of cases in the sample used to create the item statistic.

#### 2.4.3.5 "stdError" Characteristic Description

The description of the "stdError" characteristic for the "OrdinaryStatistic" class is given in Table 2.4.3.5.

Table 2.4.3.5 Description of the "stdError" characteristic for the "OrdinaryStatistic" class.
Descriptor | Definition
--- | ---
Characteristic Name | stdError
Data Type | Double (Primitive-type)
Value Space | See Appendix A1.3.
Scope | Local ("-")
Multiplicity | [0..1]
Description | The standard error of the item statistic, also known as the variance.

#### 2.4.3.6 "stdDeviation" Characteristic Description

The description of the "stdDeviation" characteristic for the "OrdinaryStatistic" class is given in Table 2.4.3.6.

Table 2.4.3.6 Description of the "stdDeviation" characteristic for the "OrdinaryStatistic" class.
Descriptor | Definition
--- | ---
Characteristic Name | stdDeviation
Data Type | Double (Primitive-type)
Value Space | See Appendix A1.3.
Scope | Local ("-")
Multiplicity | [0..1]
Description | The standard deviation of the item statistic (i.e. the square root of the standard error).

#### 2.4.3.7 "lastUpdated" Characteristic Description

The description of the "lastUpdated" characteristic for the "OrdinaryStatistic" class is given in Table 2.4.3.7.

Table 2.4.3.7 Description of the "lastUpdated" characteristic for the "OrdinaryStatistic" class.
Descriptor | Definition
--- | ---
Characteristic Name | lastUpdated
Data Type | Date
Value Space | Container [ DerivedType ]
Scope | Local ("-")
Multiplicity | [0..1]
Description | Date of the last update to the item statistic value.

#### 2.4.3.8 "targetObject" Attribute Description

The description of the "targetObject" attribute for the "OrdinaryStatistic" class is given in Table 2.4.3.8.

Table 2.4.3.8 Description of the "targetObject" attribute for the "OrdinaryStatistic" class.
Descriptor | Definition
--- | ---
Attribute Name | targetObject
Data Type | TargetObject
Value Space | Container [ DerivedType ]
Scope | Local ("-")
Multiplicity | [1.. unbounded]
Description | The targetObject is used to refer to an assessment object. This object may be an assessmentItem or some other type of object defined outside the scope of this specification, for example, an entire test. In some cases it is desirable to refer not just to the assessment object but to a specific part of that object, in which case the optional partIdentifier can be used.

#### 2.4.3.9 "value" Attribute Description

The description of the "value" attribute for the "OrdinaryStatistic" class is given in Table 2.4.3.9.

Table 2.4.3.9 Description of the "value" attribute for the "OrdinaryStatistic" class.
Descriptor | Definition
--- | ---
Attribute Name | value
Data Type | Value
Value Space | Container [ DerivedType ]
Scope | Local ("-")
Multiplicity | [1]
Description | The value of the associated ordinary statistic.

## 2.5. Abstract Class Descriptions

All of the abstract data classes used within this Information Model are described in this Section. The syntax and semantics for this representation is described in Appendix A1.2.

### 2.5.1 ItemStatistic Class Description

The data model for the "ItemStatistic" class is shown in Figure 2.5.1 and the accompanying definition in Table 2.5.1

Figure 2.5.1 - ItemStatistic class definitions.

Table 2.5.1 Description of the "ItemStatistic" class.
Descriptor | Definition
--- | ---
Class Name | ItemStatistic
Class Type | Abstract Container [ Selection ]
Parents | The set of parent classes are: UsageData
Derived Classes | There are no derived classes.
Super Classes | This class is not derived from another class.
Characteristics | There are no characteristics.
Children | The set of children attributes are: ordinaryStatistic categorizedStatistic
Description | This abstract class requires a choice of its children i.e. either an 'ordinaryStatistic' or a 'categorizedStatistic'.

#### 2.5.1.1 "ordinaryStatistic" Attribute Description

The description of the "ordinaryStatistic" attribute for the "ItemStatistic" class is given in Table 2.5.1.1.

Table 2.5.1.1 Description of the "ordinaryStatistic" attribute for the "ItemStatistic" class.
Descriptor | Definition
--- | ---
Attribute Name | ordinaryStatistic
Data Type | OrdinaryStatistic
Value Space | Container [ Sequence ]
Scope | Local ("-")
Multiplicity | [1]
Description | An item statistic that consists of a single numeric value.

#### 2.5.1.2 "categorizedStatistic" Attribute Description

The description of the "categorizedStatistic" attribute for the "ItemStatistic" class is given in Table 2.5.1.2.

Table 2.5.1.2 Description of the "categorizedStatistic" attribute for the "ItemStatistic" class.
Descriptor | Definition
--- | ---
Attribute Name | categorizedStatistic
Data Type | CategorizedStatistic
Value Space | Container [ Sequence ]
Scope | Local ("-")
Multiplicity | [1]
Description | An item statistic that consists of multiple values, e.g. IRT Dispersion Parameters.

## 2.6. Derived Class Descriptions

All of the derived data classes used within this Information Model are described in this Section. The syntax and semantics for this representation is described in Appendix A1.2.

### 2.6.1 Date Class Description

The data model for the "Date" class is shown in Figure 2.6.1 and the accompanying definition in Table 2.6.1.

Figure 2.6.1 - Date class definitions.

Table 2.6.1 Description of the "Date" class.
Descriptor | Definition
--- | ---
Class Name | Date
Class Type | Container [ DerivedType ]
Parents | The set of parent classes are: CategorizedStatistic OrdinaryStatistic
Derived Classes | There are no derived classes.
Super Classes | The set of classes from which this class is derived: Date (PrimitiveType)
Characteristics | There are no characteristics.
Children | The set of children attributes are: pattern
Description | The date as per the [ISO 8601] definition in the format YYYY-MM-DD.

#### 2.6.1.1 "pattern" Attribute Description

The description of the "pattern" attribute for the "Date" class is given in Table 2.6.1.

Table 2.6.1 Description of the "pattern" attribute for the "Date" class.
Descriptor | Definition
--- | ---
Attribute Name | pattern
Data Type | String (Primitive-type)
Value Space | See Appendix A1.3. Default = "[0-9]{4}-[0-9]{2}-[0-9]{2}".
Scope | Local ("-")
Multiplicity | [1]
Description | Ensures the date value is in the form YYYY-MM-DD where 'Y', 'M' and 'D' are numbers in the range 0-9.

### 2.6.2 Identifier Class Description

The data model for the "Identifier" class is shown in Figure 2.6.2 and the accompanying definition in Table 2.6.2.

Figure 2.6.2 - Identifier class definitions.

Table 2.6.2 Description of the "Identifier" class.
Descriptor | Definition
--- | ---
Class Name | Identifier
Class Type | Container [ DerivedType ]
Parents | The set of parent classes are: CategorizedStatistic OrdinaryStatistic TargetObject Value
Derived Classes | There are no derived classes.
Super Classes | The set of classes from which this class is derived: NCName (PrimitiveType)
Characteristics | There are no characteristics.
Children | There are no children.
Description | An identifier is simply a logical reference to another object in the item, such as an itemVariable or choice. An identifier is a string of characters that must start with a Letter or an underscore ('_') and contain only Letters, underscores, hyphens ('-'), period ('.', a.k.a. full-stop), Digits, CombiningChars and Extenders. Identifiers containing the period character are reserved for use in prefixing, as described in the definition of variable. The character classes Letter, Digit, CombiningChar and Extender are defined in the Extensible Markup Language (XML) 1.0 (Second Edition) [XML, 00]. Note particularly that identifiers may not contain the colon (':') character. Identifiers should have no more than 32 characters for compatibility with version 1. They are always compared case-sensitively.

### 2.6.3 MapEntry Class Description

The data model for the "MapEntry" class is shown in Figure 2.6.3 and the accompanying definition in Table 2.6.3.

Figure 2.6.3 - MapEntry class definitions.

Table 2.6.3 Description of the "MapEntry" class.
Descriptor | Definition
--- | ---
Class Name | MapEntry
Class Type | Container [ DerivedType ]
Parents | The set of parent classes are: Mapping
Derived Classes | There are no derived classes.
Super Classes | The set of classes from which this class is derived: Empty (PrimitiveType)
Characteristics | The set of characteristics are: mapKey mappedValue caseSensitive
Children | There are no children.
Description | A map is defined by a set of mapEntries, each of which maps a single value from the source set onto a single float.

#### 2.6.3.1 "mapKey" Characteristic Description

The description of the "mapKey" characteristic for the "MapEntry" class is given in Table 2.6.3.1.

Table 2.6.3.1 Description of the "mapKey" characteristic for the "MapEntry" class.
Descriptor | Definition
--- | ---
Characteristic Name | mapKey
Data Type | NormalizedString (Primitive-type)
Value Space | See Appendix A1.3.
Scope | Local ("-")
Multiplicity | [1]
Description | The source value.

#### 2.6.3.2 "mappedValue" Characteristic Description

The description of the "mappedValue" characteristic for the "MapEntry" class is given in Table 2.6.3.2.

Table 2.6.3.2 Description of the "mappedValue" characteristic for the "MapEntry" class.
Descriptor | Definition
--- | ---
Characteristic Name | mappedValue
Data Type | Double (Primitive-type)
Value Space | See Appendix A1.3.
Scope | Local ("-")
Multiplicity | [1]
Description | The mapped value.

#### 2.6.3.3 "caseSensitive" Characteristic Description

The description of the "caseSensitive" characteristic for the "MapEntry" class is given in Table 2.6.3.3.

Table 2.6.3.3 Description of the "caseSensitive" characteristic for the "MapEntry" class.
Descriptor | Definition
--- | ---
Characteristic Name | caseSensitive
Data Type | Boolean (Primitive-type)
Value Space | See Appendix A1.3.
Scope | Local ("-")
Multiplicity | [0..1]
Description | Used to control whether or not a mapEntry string is matched case sensitively.

### 2.6.4 TargetObject Class Description

The data model for the "TargetObject" class is shown in Figure 2.6.4 and the accompanying definition in Table 2.6.4.

Figure 2.6.4 - TargetObject class definitions.

Table 2.6.4 Description of the "TargetObject" class.
Descriptor | Definition
--- | ---
Class Name | TargetObject
Class Type | Container [ DerivedType ]
Parents | The set of parent classes are: CategorizedStatistic OrdinaryStatistic
Derived Classes | There are no derived classes.
Super Classes | The set of classes from which this class is derived: Empty (PrimitiveType)
Characteristics | The set of characteristics are: identifier partIdentifier
Children | There are no children.
Description | The targetObject is used to refer to an assessment object. This object may be an assessmentItem or some other type of object defined outside the scope of this specification, for example, an entire test. In some cases it is desirable to refer not just to the assessment object but to a specific part of that object, in which case the optional partIdentifier can be used.

#### 2.6.4.1 "identifier" Characteristic Description

The description of the "identifier" characteristic for the "TargetObject" class is given in Table 2.6.4.1.

Table 2.6.4.1 Description of the "identifier" characteristic for the "TargetObject" class.
Descriptor | Definition
--- | ---
Characteristic Name | identifier
Data Type | String (Primitive-type)
Value Space | See Appendix A1.3.
Scope | Local ("-")
Multiplicity | [1]
Description | The identifier of the assessmentItem or other target object.

#### 2.6.4.2 "partIdentifier" Characteristic Description

The description of the "partIdentifier" characteristic for the "TargetObject" class is given in Table 2.6.4.2.

Table 2.6.4.2 Description of the "partIdentifier" characteristic for the "TargetObject" class.
Descriptor | Definition
--- | ---
Characteristic Name | partIdentifier
Data Type | Identifier
Value Space | Container [ DerivedType ]
Scope | Local ("-")
Multiplicity | [0..1]
Description | An optional identifier to a specific part (e.g. an itemVariable) defined within the assessment object. In the case of an assessmentItem the partIdentifier typically refers to an outcome variable but can refer to other objects identified in the same namespace, such as a specific choice within an interaction. If no partIdentifier is given the statistic is considered to refer to the target object as a whole.

### 2.6.5 Value Class Description

The data model for the "Value" class is shown in Figure 2.6.5 and the accompanying definition in Table 2.6.5.

Figure 2.6.5 - Value class definitions.

Table 2.6.5 Description of the "Value" class.
Descriptor | Definition
--- | ---
Class Name | Value
Class Type | Container [ DerivedType ]
Parents | The set of parent classes are: OrdinaryStatistic
Derived Classes | There are no derived classes.
Super Classes | The set of classes from which this class is derived: NormalizedString (PrimitiveType)
Characteristics | The set of characteristics are: fieldIdentifier baseType
Children | There are no children.
Description | A class that can represent a single value of any baseType in variable declarations and result reports. The base-type is defined by the baseType attribute of the declaration except in the case of variables with record cardinality.

#### 2.6.5.1 "fieldIdentifier" Characteristic Description

The description of the "fieldIdentifier" characteristic for the "Value" class is given in Table 2.6.5.1.

Table 2.6.5.1 Description of the "fieldIdentifier" characteristic for the "Value" class.
Descriptor | Definition
--- | ---
Characteristic Name | fieldIdentifier
Data Type | Identifier
Value Space | Container [ DerivedType ]
Scope | Local ("-")
Multiplicity | [0..1]
Description | This attribute is only used for specifying the field identifier for a value that forms part of a record.

#### 2.6.5.2 "baseType" Characteristic Description

The description of the "baseType" characteristic for the "Value" class is given in Table 2.6.5.2.

Table 2.6.5.2 Description of the "baseType" characteristic for the "Value" class.
Descriptor | Definition
--- | ---
Characteristic Name | baseType
Data Type | BaseType
Value Space | Enumerated value set of: { boolean | directedPair | duration | file | float | identifier | integer | pair | point | string | uri }
Scope | Local ("-")
Multiplicity | [0..1]
Description | This attribute is only used for specifying the base-type of a value that forms part of a record.

## 2.7. Enumerated Vocabulary Descriptions

All of the enumerated vocabularies used within this Information Model are described in this Section. The syntax and semantics for this representation is described in Appendix A1.4.

### 2.7.1 BaseType Vocabulary Description

A base-type is simply a description of a set of atomic values (atomic to this specification). Note that several of the baseTypes used to define the runtime data model have identical definitions to those of the basic data types used to define the values for attributes in the specification itself. The use of an enumeration to define the set of baseTypes used in the runtime model, as opposed to the use of classes with similar names, is designed to help distinguish between these two distinct levels of modelling.The data model for the "BaseType" enumerated class is shown in Figure 2.7.1 and the accompanying vocabulary definition in Table 2.7.1.

Figure 2.7.1 - BaseType class definitions.

Table 2.7.1 Description of the "BaseType" enumerated vocabulary terms.
Term | Definition
--- | ---
boolean | The set of boolean values is the same as the set of values defined by the boolean primitveType.
directedPair | A directedPair value represents a pair of identifiers corresponding to a directed association between two objects. The two identifiers correspond to the source and destination objects.
duration | A duration value specifies a distance (in time) between two time points. In other words, a time period as defined by [ISO 8601], but represented as a single float that records time in seconds. Durations may have a fractional part. Durations are represented using the xsd:double datatype rather than xsd:dateTime for convenience and backward compatibility.
file | A file value is any sequence of octets (bytes) qualified by a content-type and an optional filename given to the file (for example, by the candidate when uploading it as part of an interaction). The content type of the file is one of the MIME types defined by [RFC 2045].
float | The set of float values is the same as the set of values defined by the float primitiveType.
identifier | The set of identifier values is the same as the set of values defined by the identifier class.
integer | The set of integer values is the same as the set of values defined by the integer primitiveType.
pair | A pair value represents a pair of identifiers corresponding to an association between two objects. The association is undirected so (A,B) and (B,A) are equivalent.
point | A point value represents an integer tuple corresponding to a graphic point. The two integers correspond to the horizontal (x-axis) and vertical (y-axis) positions respectively. The up/down and left/right senses of the axes are context dependent.
string | The set of string values is the same as the set of values defined by the string primitiveType.
uri | A URI value is a Uniform Resource Identifier as defined by [URI, 98].

## 2.8. External Vocabularies

All of the external vocabularies used within this Information Model are described in this Section. The syntax and semantics for this representation is described in Appendix A1.

### 2.8.1 "Distractor Statistics" External Vocabulary

The set of terms that would be used to collect distractor statistics. This is the value that will be entered in the 'name' element. The definition of the vocabulary is given in Table 2.8.1.

Table 2.8.1 Description of the "Distractor Statistics" external vocabulary terms.
Term | Definition
--- | ---
NumberChoosingResponse |
Caption: | The number of people choosing a specified response or getting a specified code.
Description: | Equal to the number of individuals that selected the response option. This can also be used for the number of individuals that received a certain rating on a judged item such as an essay question.
ParentChoosingResponse |
Caption: | The percent of people choosing a specified response or getting a specified code.
Description: | Equal to the percent of test takers that selected the response option. This can also be used for the percent of individuals that received a certain rating on a judged item such as an essay question.
PTbis-Response |
Caption: | r-pointbiserial for Response
Description: | A group-dependent measure of the discrimination of the response option, the pointbiserial correlation between selection of the response option and a criterion such as the total score on the test.
AISResponse |
Caption: | Average Item Score for Response
Description: | Equal to the mean of the item scores for the group of individuals that selected the response option.

### 2.8.2 "Item Statistics" External Vocabulary

The set of terms that would be used to collect the item statistics. This is the value that will be entered in the 'name' element. The definition of the vocabulary is given in Table 2.8.2.

Table 2.8.2 Description of the "Item Statistics" external vocabulary terms.
Term | Definition
--- | ---
D-Param |
Caption: | IRT d parameter
Description: | A measure of the dispersion of the item computed using the IRT method.
Score_Conversion |
Caption: | Score Conversion Table
Description: | Raw scores and their corresponding converted values e.g. the values to be used in score reports.
Fifths_Table_Second_Highest |
Caption: | Fifths_Table_Second_Highest
Description: | Count of examinees in the second highest fifth of the test score distribution who selected the specified option.
Fifths_Table_Lowest |
Caption: | Fifths_Table_Lowest
Description: | Count of examinees in the lowest fifth of the test score distribution who selected the specified option.
Fifths_Table_Second_Lowest |
Caption: | Fifths_Table_Second_Lowest
Description: | Count of examinees in the second lowest fifth of the test score distribution who selected the specified option.
Fifths_Table_Middle |
Caption: | Fifths_Table_Middle
Description: | Count of examinees in the middle fifth of the test score distribution who selected the specified option.
Fifths_Table_Highest |
Caption: | Fifths_Table_Highest
Description: | Count of examinees in the highest fifth of the test score distribution who selected the specified option.
AIS |
Caption: | Average Item Score
Description: | A group-dependent measure of item difficulty. Equal to the mean of the item scores for a group of individuals. For a rights-only dichotomously scored test, equivalent to the percent answering the item correctly (P-value).
A-Param |
Caption: | IRT a parameter
Description: | Index of item discrimination based on item response theory.
B-Param |
Caption: | IRT b parameter
Description: | Index of item difficulty based on item response theory.
C-Param |
Caption: | IRT c parameter
Description: | The lower asymptote of the item response function. Generally an index of guessing i.e. the probability of getting the item correct for very low ability examinees.
P-value |
Caption: | P-value
Description: | A group-dependent measure of item difficulty. It is equal to the percent answering the item correctly.
PHI |
Caption: | Phi coefficient
Description: | A group-dependent measure of item discrimination, Phi is the correlation of two dichotomous variables. In item analysis, it is generally the correlation between getting an item right or wrong and some dichotomous variable e.g. pass, fail.
PTbis |
Caption: | r-pointbiserial
Description: | A group-dependent measure of item discrimination, r-pointbiserial is the point biserial correlation between the score on a dichotomous item and a criterion which is a variable that can take many possible values, such as total score on the test.
rbis |
Caption: | r-biserial
Description: | A group-dependent measure of item discrimination, r-biserial is an estimate of the biserial correlation between a latent continuous variable hypothesised to underlie performance on a dichotomous item (i.e. item score) and a criterion which is a variable that can take many possible vales, such as total score on the test.
Polyserial |
Caption: | Polyserial
Description: | The polyserial correlation is the generalization of the biserial correlation for use with either dichotomous or polytomous items. For example, it may be the generalized form of the correlation with a criterion. It is the correlation of the item score with some continuous variable, usually the total score on the test.

toc | top

# 3. XSD Binding

## 3.1. XSD Binding Overview

The XSD binding is described using a set of tables derived from the UML representation and a set of XML code snippets. The binding description consists of:

- UML/XSD Mapping Rules - the mapping rules that show the relationship between the information model (the UML representation) and the corresponding XSD components;
- XSD Files and Namespaces - the set of XSD files and the namespaces used within those files;
- Description of the XSD - the detailed description of the actual XSD (the XSD listing is provided in Appendix C);
- The Schematron Rules - the set of Schematron rules that have been created to further impose the constraints on the XML instances that are required by the information model but not possible using the standard XSD features;
- VDEX Binding - the details of how the external vocabularies are bound to the IMS VDEX representation (the VDEX files are listed in Appendix D ).

An explanation of the structure and terms used XSD binding tables is given in Appendix B.

## 3.2. UML to XML/XSD Mapping

### 3.2.1 Root Attribute UML/XSD Mapping

The UML/XSD Mapping for the UML Root Attributes to the XSD Root Elements is given in Table 3.2.1. The syntax and semantics for this representation is described in Appendix B1.1.

Table 3.2.1 UML/XSD Mapping for the Root Attributes.
Attribute Name | UML Class | XSD Name | XSD Type | XSD Data Type
--- | --- | --- | --- | ---
usageData | UsageData | usageData | Element | UsageData.Type

### 3.2.2 Root Class UML/XSD Mapping

The syntax and semantics for the Root Class UML/XSD mapping representations is described in Appendix B1.2.

#### 3.2.2.1 UsageData Root Class Mapping

The UML/XSD Mapping for the "UsageData" Root Class is given in Table 3.2.2.1.

Table 3.2.2.1 UML/XSD Mapping for the "UsageData" Root Class.
Information Model Details | XSD Binding Details
--- | ---
Name | UML Artefact | Data Type | Multiplicity | Name | Type
UsageData | Root | Container [ Sequence ] | - N/A - | UsageData.Type | ComplexType
glossary | Characteristic | PT: AnyURI | [0..1] | glossary | Attribute (Local)
ordinaryStatistic | Attribute | OrdinaryStatistic | XOR [0.. *] [1] | ordinaryStatistic | Element (Local)
categorizedStatistic | Attribute | CategorizedStatistic | XOR [0.. *] [1] | categorizedStatistic | Element (Local)

### 3.2.3 Class UML/XSD Mapping

The syntax and semantics for the Data Class UML/XSD mapping representations is described in Appendix B1.2.

#### 3.2.3.1 CategorizedStatistic Class Mapping

The UML/XSD Mapping for the "CategorizedStatistic" Class is given in Table 3.2.3.1.

Table 3.2.3.1 UML/XSD Mapping for the "CategorizedStatistic" Core Class.
Information Model Details | XSD Binding Details
--- | ---
Name | UML Artefact | Data Type | Multiplicity | Name | Type
CategorizedStatistic | Core | Container [ Sequence ] | - N/A - | CategorizedStatistic.Type | ComplexType
name | Characteristic | DT: Identifier (PT: NCName) | [1] | name | Attribute (Local)
glossary | Characteristic | PT: AnyURI | [0..1] | glossary | Attribute (Local)
context | Characteristic | PT: AnyURI | [1] | context | Attribute (Local)
caseCount | Characteristic | PT: Integer | [0..1] | caseCount | Attribute (Local)
stdError | Characteristic | PT: Double | [0..1] | stdError | Attribute (Local)
stdDeviation | Characteristic | PT: Double | [0..1] | stdDeviation | Attribute (Local)
lastUpdated | Characteristic | DT: Date (PT: Date) | [0..1] | lastUpdated | Attribute (Local)
targetObject | Attribute | DT: TargetObject (PT: Empty) | [1.. *] | targetObject | Element (Local)
mapping | Attribute | Mapping | [1] | mapping | Element (Local)

#### 3.2.3.2 Mapping Class Mapping

The UML/XSD Mapping for the "Mapping" Class is given in Table 3.2.3.2.

Table 3.2.3.2 UML/XSD Mapping for the "Mapping" Core Class.
Information Model Details | XSD Binding Details
--- | ---
Name | UML Artefact | Data Type | Multiplicity | Name | Type
Mapping | Core | Container [ Sequence ] | - N/A - | Mapping.Type | ComplexType
lowerBound | Characteristic | PT: Double | [0..1] | lowerBound | Attribute (Local)
upperBound | Characteristic | PT: Double | [0..1] | upperBound | Attribute (Local)
defaultValue | Characteristic | PT: Double | [0..1] | defaultValue | Attribute (Local)
mapEntry | Attribute | DT: MapEntry (PT: Empty) | [1.. *] | mapEntry | Element (Local)

#### 3.2.3.3 OrdinaryStatistic Class Mapping

The UML/XSD Mapping for the "OrdinaryStatistic" Class is given in Table 3.2.3.3.

Table 3.2.3.3 UML/XSD Mapping for the "OrdinaryStatistic" Core Class.
Information Model Details | XSD Binding Details
--- | ---
Name | UML Artefact | Data Type | Multiplicity | Name | Type
OrdinaryStatistic | Core | Container [ Sequence ] | - N/A - | OrdinaryStatistic.Type | ComplexType
name | Characteristic | DT: Identifier (PT: NCName) | [1] | name | Attribute (Local)
glossary | Characteristic | PT: AnyURI | [0..1] | glossary | Attribute (Local)
context | Characteristic | PT: AnyURI | [1] | context | Attribute (Local)
caseCount | Characteristic | PT: Integer | [0..1] | caseCount | Attribute (Local)
stdError | Characteristic | PT: Double | [0..1] | stdError | Attribute (Local)
stdDeviation | Characteristic | PT: Double | [0..1] | stdDeviation | Attribute (Local)
lastUpdated | Characteristic | DT: Date (PT: Date) | [0..1] | lastUpdated | Attribute (Local)
targetObject | Attribute | DT: TargetObject (PT: Empty) | [1.. *] | targetObject | Element (Local)
value | Attribute | DT: Value (PT: NormalizedString) | [1] | value | Element (Local)

### 3.2.4 Derived UML/XSD Mapping

The syntax and semantics for the Derived Class UML/XSD mapping representations is described in Appendix B1.2.

#### 3.2.4.1 Date Derived Class Mapping

The UML/XSD Mapping for the "Date" Derived Class is given in Table 3.2.4.1.

Table 3.2.4.1 UML/XSD Mapping for the "Date" Derived Class.
Information Model Details | XSD Binding Details
--- | ---
Name | UML Artefact | Data Type | Multiplicity | Name | Type
Date | Derived | PT: Date | - N/A - | Date.Type | SimpleType
pattern | Attribute | PT: String | [1] | [ No XML instance visibility ] | Restriction (Pattern) on the Primitive Type.

The syntax and semantics for the Derived Class UML/XSD mapping representations is described in Appendix B1.2.

#### 3.2.4.2 Identifier Derived Class Mapping

The UML/XSD Mapping for the "Identifier" Derived Class is given in Table 3.2.4.2.

Table 3.2.4.2 UML/XSD Mapping for the "Identifier" Derived Class.
Information Model Details | XSD Binding Details
--- | ---
Name | UML Artefact | Data Type | Multiplicity | Name | Type
Identifier | Derived | PT: NCName | - N/A - | Identifier.Type | SimpleType

The syntax and semantics for the Derived Class UML/XSD mapping representations is described in Appendix B1.2.

#### 3.2.4.3 MapEntry Derived Class Mapping

The UML/XSD Mapping for the "MapEntry" Derived Class is given in Table 3.2.4.3.

Table 3.2.4.3 UML/XSD Mapping for the "MapEntry" Derived Class.
Information Model Details | XSD Binding Details
--- | ---
Name | UML Artefact | Data Type | Multiplicity | Name | Type
MapEntry | Derived | PT: Empty | - N/A - | MapEntry.Type | ComplexType
mapKey | Characteristic | PT: NormalizedString | [1] | mapKey | Attribute (Local)
mappedValue | Characteristic | PT: Double | [1] | mappedValue | Attribute (Local)
caseSensitive | Characteristic | PT: Boolean | [0..1] | caseSensitive | Attribute (Local)

The syntax and semantics for the Derived Class UML/XSD mapping representations is described in Appendix B1.2.

#### 3.2.4.4 TargetObject Derived Class Mapping

The UML/XSD Mapping for the "TargetObject" Derived Class is given in Table 3.2.4.4.

Table 3.2.4.4 UML/XSD Mapping for the "TargetObject" Derived Class.
Information Model Details | XSD Binding Details
--- | ---
Name | UML Artefact | Data Type | Multiplicity | Name | Type
TargetObject | Derived | PT: Empty | - N/A - | TargetObject.Type | ComplexType
identifier | Characteristic | PT: String | [1] | identifier | Attribute (Local)
partIdentifier | Characteristic | DT: Identifier (PT: NCName) | [0..1] | partIdentifier | Attribute (Local)

The syntax and semantics for the Derived Class UML/XSD mapping representations is described in Appendix B1.2.

#### 3.2.4.5 Value Derived Class Mapping

The UML/XSD Mapping for the "Value" Derived Class is given in Table 3.2.4.5.

Table 3.2.4.5 UML/XSD Mapping for the "Value" Derived Class.
Information Model Details | XSD Binding Details
--- | ---
Name | UML Artefact | Data Type | Multiplicity | Name | Type
Value | Derived | PT: NormalizedString | - N/A - | Value.Type | ComplexType
fieldIdentifier | Characteristic | DT: Identifier (PT: NCName) | [0..1] | fieldIdentifier | Attribute (Local)
baseType | Characteristic | [ Enumeration (BaseType) ] | [0..1] | baseType | Attribute (Local)

### 3.2.5 Enumerated Class UML/XSD Mapping

The definition of the set of enumerated data-types used in this specification is given in Table 3.2.5. The syntax and semantics for the Enumerated Class UML/XSD mapping representations is described in Appendix B1.3.

Table 3.2.5 The UML/XSD Map Enumerated Class Definitions.
Enumeration Class Name | Description
--- | ---
BaseType | Enumerated value set of: { boolean | directedPair | duration | file | float | identifier | integer | pair | point | string | uri }.

### 3.2.6 Enumerated List Class UML/XSD Mapping

There are no enumerated list class definitions.

### 3.2.7 List Class UML/XSD Mapping

There are no list class definitions.

### 3.2.8 Union Class UML/XSD Mapping

There are no union class definitions.

### 3.2.9 Primitive Type UML/XSD Mapping

The definition of the set of primitive data-types used in this specification is given in Table 3.2.9. The syntax and semantics for the Primitive Type UML/XSD mapping representations is described in Appendix B1.5.

Table 3.2.9 The UML/XSD Map Primitive Type Definitions.
Primitive Type Name | Description
--- | ---
AnyURI | This is mapped to the XML "xs:anyURI" data-type.
Boolean | This is mapped to the XML "xs:boolean" data-type.
Date | This is mapped to the XML "xs:date" data-type.
Double | This is mapped to the XML "xs:double" data-type.
Empty | This is used to denote an element that will not contain a value i.e. it is empty. Within the XSD a Special Data-type is declared called "EmptyPrimitiveType.Type". This ensures that the associated element has NO children (but it will have XML attributes). The XSD code is:
    <xs:complexType name="EmptyPrimitiveType.Type">
        <xs:complexContent>
            <xs:restriction base="xs:anyType" />
        </xs:complexContent>
    </xs:complexType>
Integer | This is mapped to the XML "xs:integer" data-type.
NCName | This is mapped to the XML "xs:NCName" data-type.
NormalizedString | This is mapped to the XML "xs:normalizedString" data-type.
String | This is mapped to the XML "xs:string" data-type.

## 3.3. Filenames and Namespaces

### 3.3.1 Target Namespace Details

Target Namespace: | http://www.imsglobal.org/xsd/imsqti_usagedata_v2p2
Schema Location: | http://www.imsglobal.org/xsd/qti/qtiv2p2/imsqti_usagedata_v2p2.xsd

### 3.3.2 Imported Namespace Details

There are no imported classes.

### 3.3.3 Implicit Namespace Details

Feature: | XSD Language
Namespace: | http://www.w3.org/2001/XMLSchema
Schema Location: | XML Processor Resolved.
Prefix: | xs

## 3.4. Description of the XSD

### 3.4.1 Root Element Descriptions

The syntax and semantics for the Root Element XSD representations is described in Appendix B1.6.

#### 3.4.1.1 "usageData" Root Element Description

The XSD description for the "usageData" Root Element is given in Table 3.4.1.1.

Table 3.4.1.1 XSD description for the "usageData" Root Element.
Namespace | http://www.imsglobal.org/xsd/imsqti_usagedata_v2p2
Diagram |
Type | UsageData.Type
Properties |
Content | simple
MinOccurs | 1
MaxOccurs | 1
Model | ( ordinaryStatistic{1..1} | categorizedStatistic{1..1} ){0..*}
Attributes |
QName | Type | Inherited | Scope | Use | Default
--- | --- | --- | --- | --- | ---
glossary | xs:anyURI | No | Local | Optional | -
Source |
    <xs:element name="usageData" type="UsageData.Type" />

### 3.4.2 Global Element Descriptions

There are no global elements.

### 3.4.3 Attribute Group Descriptions

There are no attribute groups.

### 3.4.4 Root Complex Type Descriptions

The syntax and semantics for the Root ComplexType XSD representations is described in Appendix B1.7.

#### 3.4.4.1 UsageData.Type Root Complex Type Description

The XSD description for the "UsageData.Type" Root ComplexType is given in Table 3.4.4.1.

Table 3.4.4.1 XSD description for the "UsageData.Type" Root Complex Type.
Namespace | http://www.imsglobal.org/xsd/imsqti_usagedata_v2p2
Annotations | Usage data, most commonly item statistics, do not form part of an assessmentItem directly because they always relate to some context or domain in which the statistics are valid. Therefore, this specification defines a separate class for describing these statistics. Each statistic refers to both its context and to the assessmentItem(s) it relates to. Therefore, instances of this class are bound and packaged separately for interoperability.
Diagram |
Properties |
Abstract | false
Mixed | false
Used by |
Root Elements | usageData
Model | ( ordinaryStatistic{1..1} | categorizedStatistic{1..1} ){0..*}
Attributes |
QName | Type | Inherited | Scope | Use | Default
--- | --- | --- | --- | --- | ---
glossary | xs:anyURI | No | Local | Optional | -
Source |
    <xs:complexType name="UsageData.Type" abstract="false" mixed="false">
        <xs:sequence>
            <xs:choice minOccurs="0" maxOccurs="unbounded">
                <xs:element name="ordinaryStatistic" type="OrdinaryStatistic.Type" minOccurs="1" maxOccurs="1"/>
                <xs:element name="categorizedStatistic" type="CategorizedStatistic.Type" minOccurs="1" maxOccurs="1"/>
            </xs:choice>
        </xs:sequence>
        <xs:attribute name="glossary" use="optional" type="xs:anyURI" />
    </xs:complexType>

##### "glossary" Local Attribute Description

The XSD description for the "glossary" Local Attribute is given in the Table below.

Table - XSD description for the "glossary/UsageData.Type" Local Attribute.
Namespace | No namespace.
Type | xs:anyURI
Properties |
Use | optional
Source |
    <xs:attribute name="glossary" use="optional" type="xs:anyURI" />

##### "ordinaryStatistic" Local Element Description

The XSD description for the "ordinaryStatistic" Local Element is given in the Table below.

Table - XSD description for the "ordinaryStatistic/UsageData.Type" Local Element.
Namespace | http://www.imsglobal.org/xsd/imsqti_usagedata_v2p2
Diagram |
Type | OrdinaryStatistic.Type
Properties |
Content | complex
MinOccurs | 1
MaxOccurs | 1
Mixed | false
Model | targetObject{1..*}, value{1..1}
Attributes |
QName | Type | Inherited | Scope | Use | Default
--- | --- | --- | --- | --- | ---
name | Identifier.Type | No | Local | Required | -
glossary | xs:anyURI | No | Local | Optional | -
context | xs:anyURI | No | Local | Required | -
caseCount | xs:integer | No | Local | Optional | -
stdError | xs:double | No | Local | Optional | -
stdDeviation | xs:double | No | Local | Optional | -
lastUpdated | Date.Type | No | Local | Optional | -
Source |
    <xs:element name="ordinaryStatistic" type="OrdinaryStatistic.Type" minOccurs="1" maxOccurs="1" />

##### "categorizedStatistic" Local Element Description

The XSD description for the "categorizedStatistic" Local Element is given in the Table below.

Table - XSD description for the "categorizedStatistic/UsageData.Type" Local Element.
Namespace | http://www.imsglobal.org/xsd/imsqti_usagedata_v2p2
Diagram |
Type | CategorizedStatistic.Type
Properties |
Content | complex
MinOccurs | 1
MaxOccurs | 1
Mixed | false
Model | targetObject{1..*}, mapping{1..1}
Attributes |
QName | Type | Inherited | Scope | Use | Default
--- | --- | --- | --- | --- | ---
name | Identifier.Type | No | Local | Required | -
glossary | xs:anyURI | No | Local | Optional | -
context | xs:anyURI | No | Local | Required | -
caseCount | xs:integer | No | Local | Optional | -
stdError | xs:double | No | Local | Optional | -
stdDeviation | xs:double | No | Local | Optional | -
lastUpdated | Date.Type | No | Local | Optional | -
Source |
    <xs:element name="categorizedStatistic" type="CategorizedStatistic.Type" minOccurs="1" maxOccurs="1" />

### 3.4.5 Core Complex Type Descriptions

The syntax and semantics for the Core ComplexType XSD representations is described in Appendix B1.7.

#### 3.4.5.1 "CategorizedStatistic.Type" Core Complex Type Description

The XSD description for the "CategorizedStatistic.Type" Core ComplexType is given in Table 3.4.5.1.

Table 3.4.5.1 XSD description for the "CategorizedStatistic.Type" Core Complex Type.
Namespace | http://www.imsglobal.org/xsd/imsqti_usagedata_v2p2
Annotations | An item statistic that consists of multiple values, e.g. IRT Dispersion Parameters.
Diagram |
Properties |
Abstract | false
Mixed | false
Used by |
Elements | categorizedStatistic/UsageData.Type
Model | targetObject{1..*}, mapping{1..1}
Attributes |
QName | Type | Inherited | Scope | Use | Default
--- | --- | --- | --- | --- | ---
name | Identifier.Type | No | Local | Required | -
glossary | xs:anyURI | No | Local | Optional | -
context | xs:anyURI | No | Local | Required | -
caseCount | xs:integer | No | Local | Optional | -
stdError | xs:double | No | Local | Optional | -
stdDeviation | xs:double | No | Local | Optional | -
lastUpdated | Date.Type | No | Local | Optional | -
Source |
    <xs:complexType name="CategorizedStatistic.Type" abstract="false" mixed="false">
        <xs:sequence>
            <xs:element name="targetObject" type="TargetObject.Type" minOccurs="1" maxOccurs="unbounded" />
            <xs:element name="mapping" type="Mapping.Type" minOccurs="1" maxOccurs="1" />
        </xs:sequence>
        <xs:attribute name="name" use="required" type="Identifier.Type" />
        <xs:attribute name="glossary" use="optional" type="xs:anyURI" />
        <xs:attribute name="context" use="required" type="xs:anyURI" />
        <xs:attribute name="caseCount" use="optional" type="xs:integer" />
        <xs:attribute name="stdError" use="optional" type="xs:double" />
        <xs:attribute name="stdDeviation" use="optional" type="xs:double" />
        <xs:attribute name="lastUpdated" use="optional" type="Date.Type" />
    </xs:complexType>

##### "name" Local Attribute Description

The XSD description for the "name" Local Attribute is given in the Table below.

Table - XSD description for the "name/CategorizedStatistic.Type" Local Attribute.
Namespace | No namespace.
Type | Identifier.Type
Properties |
Use | required
Source |
    <xs:attribute name="name" use="required" type="Identifier.Type" />

##### "glossary" Local Attribute Description

The XSD description for the "glossary" Local Attribute is given in the Table below.

Table - XSD description for the "glossary/CategorizedStatistic.Type" Local Attribute.
Namespace | No namespace.
Type | xs:anyURI
Properties |
Use | optional
Source |
    <xs:attribute name="glossary" use="optional" type="xs:anyURI" />

##### "context" Local Attribute Description

The XSD description for the "context" Local Attribute is given in the Table below.

Table - XSD description for the "context/CategorizedStatistic.Type" Local Attribute.
Namespace | No namespace.
Type | xs:anyURI
Properties |
Use | required
Source |
    <xs:attribute name="context" use="required" type="xs:anyURI" />

##### "caseCount" Local Attribute Description

The XSD description for the "caseCount" Local Attribute is given in the Table below.

Table - XSD description for the "caseCount/CategorizedStatistic.Type" Local Attribute.
Namespace | No namespace.
Type | xs:integer
Properties |
Use | optional
Source |
    <xs:attribute name="caseCount" use="optional" type="xs:integer" />

##### "stdError" Local Attribute Description

The XSD description for the "stdError" Local Attribute is given in the Table below.

Table - XSD description for the "stdError/CategorizedStatistic.Type" Local Attribute.
Namespace | No namespace.
Type | xs:double
Properties |
Use | optional
Source |
    <xs:attribute name="stdError" use="optional" type="xs:double" />

##### "stdDeviation" Local Attribute Description

The XSD description for the "stdDeviation" Local Attribute is given in the Table below.

Table - XSD description for the "stdDeviation/CategorizedStatistic.Type" Local Attribute.
Namespace | No namespace.
Type | xs:double
Properties |
Use | optional
Source |
    <xs:attribute name="stdDeviation" use="optional" type="xs:double" />

##### "lastUpdated" Local Attribute Description

The XSD description for the "lastUpdated" Local Attribute is given in the Table below.

Table - XSD description for the "lastUpdated/CategorizedStatistic.Type" Local Attribute.
Namespace | No namespace.
Type | Date.Type
Properties |
Use | optional
Facets |
Pattern | [0-9]{4}-[0-9]{2}-[0-9]{2}
Source |
    <xs:attribute name="lastUpdated" use="optional" type="Date.Type" />

##### "targetObject" Local Element Description

The XSD description for the "targetObject" Local Element is given in the Table below.

Table - XSD description for the "targetObject/CategorizedStatistic.Type" Local Element.
Namespace | http://www.imsglobal.org/xsd/imsqti_usagedata_v2p2
Diagram |
Type | TargetObject.Type
Type Hierarchy | EmptyPrimitiveType.Type ^---TargetObject.Type
Properties |
Content | simple
MinOccurs | 1
MaxOccurs | unbounded
Model | Empty
Attributes |
QName | Type | Inherited | Scope | Use | Default
--- | --- | --- | --- | --- | ---
identifier | xs:string | No | Local | Required | -
partIdentifier | Identifier.Type | No | Local | Optional | -
Source |
    <xs:element name="targetObject" type="TargetObject.Type" minOccurs="1" maxOccurs="unbounded" />

##### "mapping" Local Element Description

The XSD description for the "mapping" Local Element is given in the Table below.

Table - XSD description for the "mapping/CategorizedStatistic.Type" Local Element.
Namespace | http://www.imsglobal.org/xsd/imsqti_usagedata_v2p2
Diagram |
Type | Mapping.Type
Properties |
Content | complex
MinOccurs | 1
MaxOccurs | 1
Mixed | false
Model | mapEntry{1..*}
Attributes |
QName | Type | Inherited | Scope | Use | Default
--- | --- | --- | --- | --- | ---
lowerBound | xs:double | No | Local | Optional | -
upperBound | xs:double | No | Local | Optional | -
defaultValue | xs:double | No | Local | Optional | 0
Source |
    <xs:element name="mapping" type="Mapping.Type" minOccurs="1" maxOccurs="1" />

#### 3.4.5.2 "Mapping.Type" Core Complex Type Description

The XSD description for the "Mapping.Type" Core ComplexType is given in Table 3.4.5.2.

Table 3.4.5.2 XSD description for the "Mapping.Type" Core Complex Type.
Namespace | http://www.imsglobal.org/xsd/imsqti_usagedata_v2p2
Annotations | A special class used to create a mapping from a source set of any baseType (except file and duration) to a single float. Note that mappings from values of base type float should be avoided due to the difficulty of matching floating point values, see the match operator for more details. When mapping containers the result is the sum of the mapped values from the target set. See mapResponse for details.
Diagram |
Properties |
Abstract | false
Mixed | false
Used by |
Elements | mapping/CategorizedStatistic.Type
Model | mapEntry{1..*}
Attributes |
QName | Type | Inherited | Scope | Use | Default
--- | --- | --- | --- | --- | ---
lowerBound | xs:double | No | Local | Optional | -
upperBound | xs:double | No | Local | Optional | -
defaultValue | xs:double | No | Local | Optional | 0
Source |
    <xs:complexType name="Mapping.Type" abstract="false" mixed="false">
        <xs:sequence>
            <xs:element name="mapEntry" type="MapEntry.Type" minOccurs="1" maxOccurs="unbounded" />
        </xs:sequence>
        <xs:attribute name="lowerBound" use="optional" type="xs:double" />
        <xs:attribute name="upperBound" use="optional" type="xs:double" />
        <xs:attribute name="defaultValue" use="optional" default="0" type="xs:double" />
    </xs:complexType>

##### "lowerBound" Local Attribute Description

The XSD description for the "lowerBound" Local Attribute is given in the Table below.

Table - XSD description for the "lowerBound/Mapping.Type" Local Attribute.
Namespace | No namespace.
Type | xs:double
Properties |
Use | optional
Source |
    <xs:attribute name="lowerBound" use="optional" type="xs:double" />

##### "upperBound" Local Attribute Description

The XSD description for the "upperBound" Local Attribute is given in the Table below.

Table - XSD description for the "upperBound/Mapping.Type" Local Attribute.
Namespace | No namespace.
Type | xs:double
Properties |
Use | optional
Source |
    <xs:attribute name="upperBound" use="optional" type="xs:double" />

##### "defaultValue" Local Attribute Description

The XSD description for the "defaultValue" Local Attribute is given in the Table below.

Table - XSD description for the "defaultValue/Mapping.Type" Local Attribute.
Namespace | No namespace.
Type | xs:double
Properties |
Use | optional
Default | 0
Source |
    <xs:attribute name="defaultValue" use="optional" default="0" type="xs:double" />

##### "mapEntry" Local Element Description

The XSD description for the "mapEntry" Local Element is given in the Table below.

Table - XSD description for the "mapEntry/Mapping.Type" Local Element.
Namespace | http://www.imsglobal.org/xsd/imsqti_usagedata_v2p2
Diagram |
Type | MapEntry.Type
Type Hierarchy | EmptyPrimitiveType.Type ^---MapEntry.Type
Properties |
Content | simple
MinOccurs | 1
MaxOccurs | unbounded
Model | Empty
Attributes |
QName | Type | Inherited | Scope | Use | Default
--- | --- | --- | --- | --- | ---
mapKey | xs:normalizedString | No | Local | Required | -
mappedValue | xs:double | No | Local | Required | -
caseSensitive | xs:boolean | No | Local | Optional | -
Source |
    <xs:element name="mapEntry" type="MapEntry.Type" minOccurs="1" maxOccurs="unbounded" />

#### 3.4.5.3 "OrdinaryStatistic.Type" Core Complex Type Description

The XSD description for the "OrdinaryStatistic.Type" Core ComplexType is given in Table 3.4.5.3.

Table 3.4.5.3 XSD description for the "OrdinaryStatistic.Type" Core Complex Type.
Namespace | http://www.imsglobal.org/xsd/imsqti_usagedata_v2p2
Annotations | An item statistic that consists of a single numeric value.
Diagram |
Properties |
Abstract | false
Mixed | false
Used by |
Elements | ordinaryStatistic/UsageData.Type
Model | targetObject{1..*}, value{1..1}
Attributes |
QName | Type | Inherited | Scope | Use | Default
--- | --- | --- | --- | --- | ---
name | Identifier.Type | No | Local | Required | -
glossary | xs:anyURI | No | Local | Optional | -
context | xs:anyURI | No | Local | Required | -
caseCount | xs:integer | No | Local | Optional | -
stdError | xs:double | No | Local | Optional | -
stdDeviation | xs:double | No | Local | Optional | -
lastUpdated | Date.Type | No | Local | Optional | -
Source |
    <xs:complexType name="OrdinaryStatistic.Type" abstract="false" mixed="false">
        <xs:sequence>
            <xs:element name="targetObject" type="TargetObject.Type" minOccurs="1" maxOccurs="unbounded" />
            <xs:element name="value" type="Value.Type" minOccurs="1" maxOccurs="1" />
        </xs:sequence>
        <xs:attribute name="name" use="required" type="Identifier.Type" />
        <xs:attribute name="glossary" use="optional" type="xs:anyURI" />
        <xs:attribute name="context" use="required" type="xs:anyURI" />
        <xs:attribute name="caseCount" use="optional" type="xs:integer" />
        <xs:attribute name="stdError" use="optional" type="xs:double" />
        <xs:attribute name="stdDeviation" use="optional" type="xs:double" />
        <xs:attribute name="lastUpdated" use="optional" type="Date.Type" />
    </xs:complexType>

##### "name" Local Attribute Description

The XSD description for the "name" Local Attribute is given in the Table below.

Table - XSD description for the "name/OrdinaryStatistic.Type" Local Attribute.
Namespace | No namespace.
Type | Identifier.Type
Properties |
Use | required
Source |
    <xs:attribute name="name" use="required" type="Identifier.Type" />

##### "glossary" Local Attribute Description

The XSD description for the "glossary" Local Attribute is given in the Table below.

Table - XSD description for the "glossary/OrdinaryStatistic.Type" Local Attribute.
Namespace | No namespace.
Type | xs:anyURI
Properties |
Use | optional
Source |
    <xs:attribute name="glossary" use="optional" type="xs:anyURI" />

##### "context" Local Attribute Description

The XSD description for the "context" Local Attribute is given in the Table below.

Table - XSD description for the "context/OrdinaryStatistic.Type" Local Attribute.
Namespace | No namespace.
Type | xs:anyURI
Properties |
Use | required
Source |
    <xs:attribute name="context" use="required" type="xs:anyURI" />

##### "caseCount" Local Attribute Description

The XSD description for the "caseCount" Local Attribute is given in the Table below.

Table - XSD description for the "caseCount/OrdinaryStatistic.Type" Local Attribute.
Namespace | No namespace.
Type | xs:integer
Properties |
Use | optional
Source |
    <xs:attribute name="caseCount" use="optional" type="xs:integer" />

##### "stdError" Local Attribute Description

The XSD description for the "stdError" Local Attribute is given in the Table below.

Table - XSD description for the "stdError/OrdinaryStatistic.Type" Local Attribute.
Namespace | No namespace.
Type | xs:double
Properties |
Use | optional
Source |
    <xs:attribute name="stdError" use="optional" type="xs:double" />

##### "stdDeviation" Local Attribute Description

The XSD description for the "stdDeviation" Local Attribute is given in the Table below.

Table - XSD description for the "stdDeviation/OrdinaryStatistic.Type" Local Attribute.
Namespace | No namespace.
Type | xs:double
Properties |
Use | optional
Source |
    <xs:attribute name="stdDeviation" use="optional" type="xs:double" />

##### "lastUpdated" Local Attribute Description

The XSD description for the "lastUpdated" Local Attribute is given in the Table below.

Table - XSD description for the "lastUpdated/OrdinaryStatistic.Type" Local Attribute.
Namespace | No namespace.
Type | Date.Type
Properties |
Use | optional
Facets |
Pattern | [0-9]{4}-[0-9]{2}-[0-9]{2}
Source |
    <xs:attribute name="lastUpdated" use="optional" type="Date.Type" />

##### "targetObject" Local Element Description

The XSD description for the "targetObject" Local Element is given in the Table below.

Table - XSD description for the "targetObject/OrdinaryStatistic.Type" Local Element.
Namespace | http://www.imsglobal.org/xsd/imsqti_usagedata_v2p2
Diagram |
Type | TargetObject.Type
Type Hierarchy | EmptyPrimitiveType.Type ^---TargetObject.Type
Properties |
Content | simple
MinOccurs | 1
MaxOccurs | unbounded
Model | Empty
Attributes |
QName | Type | Inherited | Scope | Use | Default
--- | --- | --- | --- | --- | ---
identifier | xs:string | No | Local | Required | -
partIdentifier | Identifier.Type | No | Local | Optional | -
Source |
    <xs:element name="targetObject" type="TargetObject.Type" minOccurs="1" maxOccurs="unbounded" />

##### "value" Local Element Description

The XSD description for the "value" Local Element is given in the Table below.

Table - XSD description for the "value/OrdinaryStatistic.Type" Local Element.
Namespace | http://www.imsglobal.org/xsd/imsqti_usagedata_v2p2
Diagram |
Type | Value.Type
Properties |
Content | simple
MinOccurs | 1
MaxOccurs | 1
Model | N/A
Attributes |
QName | Type | Inherited | Scope | Use | Default
--- | --- | --- | --- | --- | ---
fieldIdentifier | Identifier.Type | No | Local | Optional | -
baseType | [ Enumeration ] | No | Local | Optional | -
Source |
    <xs:element name="value" type="Value.Type" minOccurs="1" maxOccurs="1" />

### 3.4.6 Derived Complex Type Descriptions

The syntax and semantics for the Derived ComplexType XSD representations is described in Appendix B1.7.

#### 3.4.6.1 "MapEntry.Type" Derived Complex Type Description

The XSD description for the "MapEntry.Type" Derived Complex Type is given in Table 3.4.6.1.

Table 3.4.6.1 XSD description for the "MapEntry.Type" Derived Complex Type.
Namespace | http://www.imsglobal.org/xsd/imsqti_usagedata_v2p2
Annotations | A map is defined by a set of mapEntries, each of which maps a single value from the source set onto a single float.
Diagram |
Type Hierarchy | EmptyPrimitiveType.Type ^---MapEntry.Type
Properties |
Abstract | false
Mixed | false
Used by |
Elements | mapEntry/Mapping.Type
Model | Empty
Attributes |
QName | Type | Inherited | Scope | Use | Default
--- | --- | --- | --- | --- | ---
mapKey | xs:normalizedString | No | Local | Required | -
mappedValue | xs:double | No | Local | Required | -
caseSensitive | xs:boolean | No | Local | Optional | -
Source |
    <xs:complexType name="MapEntry.Type" abstract="false" mixed="false">
        <xs:simpleType>
            <xs:extension base="EmptyPrimitiveType.Type">
                <xs:attribute name="mapKey" use="required" type="xs:normalizedString" />
                <xs:attribute name="mappedValue" use="required" type="xs:double" />
                <xs:attribute name="caseSensitive" use="optional" type="xs:boolean" />
            </xs:extension>
        </xs:simpleType>
    </xs:complexType>

##### "mapKey" Local Attribute Description

The XSD description for the "mapKey" Local Attribute is given in the Table below.

Table - XSD description for the "mapKey/MapEntry.Type" Local Attribute.
Namespace | No namespace.
Type | xs:normalizedString
Properties |
Use | required
Source |
    <xs:attribute name="mapKey" use="required" type="xs:normalizedString" />

##### "mappedValue" Local Attribute Description

The XSD description for the "mappedValue" Local Attribute is given in the Table below.

Table - XSD description for the "mappedValue/MapEntry.Type" Local Attribute.
Namespace | No namespace.
Type | xs:double
Properties |
Use | required
Source |
    <xs:attribute name="mappedValue" use="required" type="xs:double" />

##### "caseSensitive" Local Attribute Description

The XSD description for the "caseSensitive" Local Attribute is given in the Table below.

Table - XSD description for the "caseSensitive/MapEntry.Type" Local Attribute.
Namespace | No namespace.
Type | xs:boolean
Properties |
Use | optional
Source |
    <xs:attribute name="caseSensitive" use="optional" type="xs:boolean" />

#### 3.4.6.2 "TargetObject.Type" Derived Complex Type Description

The XSD description for the "TargetObject.Type" Derived Complex Type is given in Table 3.4.6.2.

Table 3.4.6.2 XSD description for the "TargetObject.Type" Derived Complex Type.
Namespace | http://www.imsglobal.org/xsd/imsqti_usagedata_v2p2
Annotations | The targetObject is used to refer to an assessment object. This object may be an assessmentItem or some other type of object defined outside the scope of this specification, for example, an entire test. In some cases it is desirable to refer not just to the assessment object but to a specific part of that object, in which case the optional partIdentifier can be used.
Diagram |
Type Hierarchy | EmptyPrimitiveType.Type ^---TargetObject.Type
Properties |
Abstract | false
Mixed | false
Used by |
Elements | targetObject/CategorizedStatistic.Type, targetObject/OrdinaryStatistic.Type
Model | Empty
Attributes |
QName | Type | Inherited | Scope | Use | Default
--- | --- | --- | --- | --- | ---
identifier | xs:string | No | Local | Required | -
partIdentifier | Identifier.Type | No | Local | Optional | -
Source |
    <xs:complexType name="TargetObject.Type" abstract="false" mixed="false">
        <xs:simpleType>
            <xs:extension base="EmptyPrimitiveType.Type">
                <xs:attribute name="identifier" use="required" type="xs:string" />
                <xs:attribute name="partIdentifier" use="optional" type="Identifier.Type" />
            </xs:extension>
        </xs:simpleType>
    </xs:complexType>

##### "identifier" Local Attribute Description

The XSD description for the "identifier" Local Attribute is given in the Table below.

Table - XSD description for the "identifier/TargetObject.Type" Local Attribute.
Namespace | No namespace.
Type | xs:string
Properties |
Use | required
Source |
    <xs:attribute name="identifier" use="required" type="xs:string" />

##### "partIdentifier" Local Attribute Description

The XSD description for the "partIdentifier" Local Attribute is given in the Table below.

Table - XSD description for the "partIdentifier/TargetObject.Type" Local Attribute.
Namespace | No namespace.
Type | Identifier.Type
Properties |
Use | optional
Source |
    <xs:attribute name="partIdentifier" use="optional" type="Identifier.Type" />

#### 3.4.6.3 "Value.Type" Derived Complex Type Description

The XSD description for the "Value.Type" Derived Complex Type is given in Table 3.4.6.3.

Table 3.4.6.3 XSD description for the "Value.Type" Derived Complex Type.
Namespace | http://www.imsglobal.org/xsd/imsqti_usagedata_v2p2
Annotations | A class that can represent a single value of any baseType in variable declarations and result reports. The base-type is defined by the baseType attribute of the declaration except in the case of variables with record cardinality.
Diagram |
Properties |
Abstract | false
Mixed | false
Used by |
Elements | value/OrdinaryStatistic.Type
Model | N/A
Attributes |
QName | Type | Inherited | Scope | Use | Default
--- | --- | --- | --- | --- | ---
fieldIdentifier | Identifier.Type | No | Local | Optional | -
baseType | [ Enumeration ] | No | Local | Optional | -
Source |
    <xs:complexType name="Value.Type" abstract="false" mixed="false">
        <xs:simpleType>
            <xs:extension base="xs:normalizedString">
                <xs:attribute name="fieldIdentifier" use="optional" type="Identifier.Type" />
                <xs:attribute name="baseType" use="optional">
                    <xs:simpleType>
                        <xs:annotation>
                            <xs:documentation source="documentation">
                                A base-type is simply a description of a set of atomic values (atomic to this specificati-
                                on). Note that several of the baseTypes used to define the runtime data model have identi-
                                cal definitions to those of the basic data types used to define the values for attributes
                                in the specification itself. The use of an enumeration to define the set of baseTypes used
                                in the runtime model, as opposed to the use of classes with similar names, is designed to
                                help distinguish between these two distinct levels of modelling.
                            </xs:documentation>
                        </xs:annotation>
                        <xs:restriction base="xs:string">
                            <xs:enumeration value="boolean" />
                            <xs:enumeration value="directedPair" />
                            <xs:enumeration value="duration" />
                            <xs:enumeration value="file" />
                            <xs:enumeration value="float" />
                            <xs:enumeration value="identifier" />
                            <xs:enumeration value="integer" />
                            <xs:enumeration value="pair" />
                            <xs:enumeration value="point" />
                            <xs:enumeration value="string" />
                            <xs:enumeration value="uri" />
                        </xs:restriction>
                    </xs:simpleType>
                </xs:attribute>
            </xs:extension>
        </xs:simpleType>
    </xs:complexType>

##### "fieldIdentifier" Local Attribute Description

The XSD description for the "fieldIdentifier" Local Attribute is given in the Table below.

Table - XSD description for the "fieldIdentifier/Value.Type" Local Attribute.
Namespace | No namespace.
Type | Identifier.Type
Properties |
Use | optional
Source |
    <xs:attribute name="fieldIdentifier" use="optional" type="Identifier.Type" />

##### "baseType" Local Attribute Description

The XSD description for the "baseType" Local Attribute is given in the Table below.

Table - XSD description for the "baseType/Value.Type" Local Attribute.
Namespace | No namespace.
Type | Enumeration [Restriction of "xs:string"]
Properties |
Use | optional
Facets |
Enumeration | boolean
Enumeration | directedPair
Enumeration | duration
Enumeration | file
Enumeration | float
Enumeration | identifier
Enumeration | integer
Enumeration | pair
Enumeration | point
Enumeration | string
Enumeration | uri
Source |
    <xs:attribute name="baseType" use="optional">
        <xs:simpleType>
            <xs:restriction base="xs:string">
                <xs:enumeration value="boolean" />
                <xs:enumeration value="directedPair" />
                <xs:enumeration value="duration" />
                <xs:enumeration value="file" />
                <xs:enumeration value="float" />
                <xs:enumeration value="identifier" />
                <xs:enumeration value="integer" />
                <xs:enumeration value="pair" />
                <xs:enumeration value="point" />
                <xs:enumeration value="string" />
                <xs:enumeration value="uri" />
            </xs:restriction>
        </xs:simpleType>
    </xs:attribute>

### 3.4.7 Simple Type Descriptions

The syntax and semantics for the SimpleType XSD representations is described in Appendix B1.8.

#### 3.4.7.1 "Date.Type" Simple Type Description

The XSD description for the "Date.Type" SimpleType is given in Table 3.4.7.1.

Table 3.4.7.1 XSD description for the "Date.Type" Simple Type.
Namespace | http://www.imsglobal.org/xsd/imsqti_usagedata_v2p2
Diagram |
Type | xs:date
Facets |
Pattern | [0-9]{4}-[0-9]{2}-[0-9]{2}
Used by |
Attributes | lastUpdated/CategorizedStatistic.Type, lastUpdated/OrdinaryStatistic.Type
Source |
    <xs:simpleType name="Date.Type">
        <xs:restriction base="xs:date">
            <xs:pattern value="[0-9]{4}-[0-9]{2}-[0-9]{2}" />
        </xs:restriction>
    </xs:simpleType>

#### 3.4.7.2 "Identifier.Type" Simple Type Description

The XSD description for the "Identifier.Type" SimpleType is given in Table 3.4.7.2.

Table 3.4.7.2 XSD description for the "Identifier.Type" Simple Type.
Namespace | http://www.imsglobal.org/xsd/imsqti_usagedata_v2p2
Diagram |
Type | xs:NCName
Used by |
Attributes | name/CategorizedStatistic.Type, name/OrdinaryStatistic.Type, partIdentifier/TargetObject.Type, fieldIdentifier/Value.Type
Source |
    <xs:simpleType name="Identifier.Type">
        <xs:restriction base="xs:NCName" />
    </xs:simpleType>

## 3.5. The Schematron Rules

There are no schematron rules used in this XSD binding of the specification.

## 3.6. The VDEX Vocabulary Bindings

Each external vocabulary is bound to an IMS VDEX instance and is described in this Section. The syntax and semantics for this representation is described in Appendix B1.11.

### 3.6.1 "Distractor Statistics" Vocabulary VDEX Binding Description

The set of terms that would be used to collect distractor statistics. This is the value that will be entered in the 'name' element. The VDEX description for the "Distractor Statistics" vocabulary is given in Table 3.6.1.

Table 3.6.1 VDEX description for the "Distractor Statistics" Vocabulary.
Name | IMS Global QTI Glossary of Terms for Usage Data Distractor Statistics
Identifier | http://www.imsglobal.org/qti/qtiv2p2/distractorstatisticsglossaryv1p0
Location | http://www.imsglobal.org/question/qtiv2p2/glossaries/distractorstatisticsglossaryv1p0.xml
Type | glossaryOrDictionary
Publisher | IMS Global Learning Consortium Inc.
Keywords | QTIv2.2, Usage Data, Distractor Statistics Glossary
Terms |
Name | Status | Caption | Description
--- | --- | --- | ---
NumberChoosingResponse | Final | The number of people choosing a specified response or getting a specified code. | Equal to the number of individuals that selected the response option. This can also be used for the number of individuals that received a certain rating on a judged item such as an essay question.
ParentChoosingResponse | Final | The percent of people choosing a specified response or getting a specified code. | Equal to the percent of test takers that selected the response option. This can also be used for the percent of individuals that received a certain rating on a judged item such as an essay question.
PTbis-Response | Final | r-pointbiserial for Response | A group-dependent measure of the discrimination of the response option, the pointbiserial correlation between selection of the response option and a criterion such as the total score on the test.
AISResponse | Final | Average Item Score for Response | Equal to the mean of the item scores for the group of individuals that selected the response option.

### 3.6.2 "Item Statistics" Vocabulary VDEX Binding Description

The set of terms that would be used to collect the item statistics. This is the value that will be entered in the 'name' element. The VDEX description for the "Item Statistics" vocabulary is given in Table 3.6.2.

Table 3.6.2 VDEX description for the "Item Statistics" Vocabulary.
Name | IMS Global QTI Glossary of Terms for Usage Data Item Statistics
Identifier | http://www.imsglobal.org/qti/qtiv2p2/itemstatisticsglossaryv1p0
Location | http://www.imsglobal.org/question/qtiv2p2/glossaries/itemstatisticsglossaryv1p0.xml
Type | glossaryOrDictionary
Publisher | IMS Global Learning Consortium Inc.
Keywords | QTIv2.2, Usage Data, Item Statistics Glossary
Terms |
Name | Status | Caption | Description
--- | --- | --- | ---
D-Param | Final | IRT d parameter | A measure of the dispersion of the item computed using the IRT method.
Score_Conversion | Final | Score Conversion Table | Raw scores and their corresponding converted values e.g. the values to be used in score reports.
Fifths_Table_Second_Highest | Final | Fifths_Table_Second_Highest | Count of examinees in the second highest fifth of the test score distribution who selected the specified option.
Fifths_Table_Lowest | Final | Fifths_Table_Lowest | Count of examinees in the lowest fifth of the test score distribution who selected the specified option.
Fifths_Table_Second_Lowest | Final | Fifths_Table_Second_Lowest | Count of examinees in the second lowest fifth of the test score distribution who selected the specified option.
Fifths_Table_Middle | Final | Fifths_Table_Middle | Count of examinees in the middle fifth of the test score distribution who selected the specified option.
Fifths_Table_Highest | Final | Fifths_Table_Highest | Count of examinees in the highest fifth of the test score distribution who selected the specified option.
AIS | Final | Average Item Score | A group-dependent measure of item difficulty. Equal to the mean of the item scores for a group of individuals. For a rights-only dichotomously scored test, equivalent to the percent answering the item correctly (P-value).
A-Param | Final | IRT a parameter | Index of item discrimination based on item response theory.
B-Param | Final | IRT b parameter | Index of item difficulty based on item response theory.
C-Param | Final | IRT c parameter | The lower asymptote of the item response function. Generally an index of guessing i.e. the probability of getting the item correct for very low ability examinees.
P-value | Final | P-value | A group-dependent measure of item difficulty. It is equal to the percent answering the item correctly.
PHI | Final | Phi coefficient | A group-dependent measure of item discrimination, Phi is the correlation of two dichotomous variables. In item analysis, it is generally the correlation between getting an item right or wrong and some dichotomous variable e.g. pass, fail.
PTbis | Final | r-pointbiserial | A group-dependent measure of item discrimination, r-pointbiserial is the point biserial correlation between the score on a dichotomous item and a criterion which is a variable that can take many possible values, such as total score on the test.
rbis | Final | r-biserial | A group-dependent measure of item discrimination, r-biserial is an estimate of the biserial correlation between a latent continuous variable hypothesised to underlie performance on a dichotomous item (i.e. item score) and a criterion which is a variable that can take many possible vales, such as total score on the test.
Polyserial | Final | Polyserial | The polyserial correlation is the generalization of the biserial correlation for use with either dichotomous or polytomous items. For example, it may be the generalized form of the correlation with a criterion. It is the correlation of the item score with some continuous variable, usually the total score on the test.

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# 4. Extending and Profiling the Data Model

## 4.1. Extending the Data Model

The QTI Usage specification contains NO exension points. Any proprietary extension is non-conformant. The behavior of a system that receives a QTI Usage Data instance that contains proprietary extensions in undefined (however a system should handle such violations in a controlled manner).

The Usage Data external vocabularies (contained in the VDEX files) can be extended to support proprietary terms. It is recommended that IMS be informed of such changes so that the new additions can be formally adopted. The proprietary terms must be marked as such in the 'status' field of the term in the VDEX file. It may be appropriate to give the changed VDEX file a new name and identifier.

## 4.2. Profiling the Data Model

This specification may be profiled. A profile must be formal subset of the base specification. This ensures that, with the exception of namespace/schema location changes, any instance which is compliant to the profile MUST also be compliant to the base specification. This means that a profile must only increase the constraints on the properties of the data model. For example, an element with a multiplicity of [0..1] can have this changed to [1..1] but NOT [0..*]. Proprietary extensions are ONLY permitted as defined by the base specification.

It is strongly recommended that a profile of this specification is undertaken either by, or with the close support, of IMS Global. However, no matter who is responsible for creating the profile artefacts (documents, XSDs, etc.), it is strongly recommended that the IMS specification tools are used. This will ensure that the artefacts are consistent with the base specifications and that useful support documentation is automatically produced e.g. creation of a document that summarises the differences between the base specification and the profile. Organizations wishing to produce a profile of this specification should contact Lisa Mattson (IMS Global Chief Operations Officer) at: lmattson@imsglobal.org.

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# Appendix A Modelling Concepts and Terms

## A1 Data Model Descriptions

### A1.1 Data Model Diagrams

Table A1.1 provides the key to the descriptions of data model diagrams.

Table A1.1 The key to the descriptions of data model diagrams.
Feature | Definition and Usage
--- | ---
Data Model Package | Each data model description is enclosed in a UML Package that has the stereotype of « dataModel » under which is the name of the data model diagram being described. Only one logical data model can be described.
DerivedType Class | This is a class that is identified by the stereotype « DerivedType » under which is the name of the data-type. A derived class is one that is derived either from another derived class or a PrimitiveType class.
Enumeration Class | This is a class that is identified by the stereotype « Enumeration » under which is the name of the enumeration data-type. The enumeration class consists of the list of tokens that are the permitted values of the assigned attribute.
Enumerated List Class | This is a class that is identified by the stereotype « EnumeratedList » under which is the name of the enumerated list data-type. The enumeration list class consists of the list of tokens that are the permitted values of the assigned attribute. A list of tokens is permitted using comma separation.
PrimitiveType Class | This is a class that is identified by the stereotype « PrimitveType » under which is the name of the primitive data-type. A PrimitiveType is one of the many base data-types on which a data model can be built (see Appendix A1.3 for the set of primitive types that are available).
Selection Class | This is a class that is identified by the stereotype « Selection » under which is the name of the data-type. The selection means that only one of the listed attributes make occur in an instance. If this is an abstract class then multiple iterations of the instance may occur and the multiplicity of the attribute defines the constraints on the number of times the attribute can occur in the full instance. If the stereotype and associated name of the class are in italics this denotes the class is abstract.
Sequence Class | This is a class that is identified by the stereotype « Sequence » under which is the name of the data-type. The sequence means that the listed attributes must occur only in the order of the attributes listed on the class. The associated multiplicity defines the number of times the attribute may occur consecutively in the instance. If the stereotype and associated name of the class are in italics this denotes the class is abstract.
Unordered Class | This is a class that is identified by the stereotype « Unordered » under which is the name of the data-type. The unordering means that the listed attributes may occur in any order but the associated multiplicity for the attribute must be followed (when binding to XML this requires the use of Schematron rules to enforce the multiplicity). If the stereotype and associated name of the class are in italics this denotes the class is abstract.
List Class | This is a class that is identified by the stereotype « List » under which is the name of the data-type. A list class is one in which the associated instance will consist of a list of objects that conform to the permitted data-types of the list (the superclasses for the list class). The terms in the list are separated by a space.
Union Class | This is a class that is identified by the stereotype « Union » under which is the name of the data-type. A union class is one in which the associated instance will consist of a objects that conform to the any of the permitted data-types of the union (the superclasses for the union class).
Characteristic Description | Many classes contain a set of characteristics (the set of characteristics are listed under the stereotype « Characteristics »). Each characteristic description consists of the scope, name, data-type and multiplicity (see Appendix A1.3 for a more complete description). Note that when bound to XSD/XML, a characteristic is mapped to an XML attribute.
Attribute Description | Many classes contain a set of attributes (the set of attributes are listed under the stereotype « Attributes »). Each attribute description consists of the scope, name, data-type and multiplicity (see Appendix A1.3 for a more complete description). Note when bound to XSD/XML, an attribute is mapped to an XML element.
Composition Arrow | This is an arrow with a filled diamond head to indicate that the child class is a composite structure of the parent class i.e. the child class only exists within the context of the parent class. This association allows complex structures to be constructed with common subcomponents.
Generalization Arrow | This is an arrow with a white arrow head to indicate the class/superclass relationship. The arrow points in the direction of generality i.e. from the class to the super class.

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### A1.2 Class Descriptions

Table A1.2 provides the key to the descriptions of the data class tables.

Table A1.2 The key to the descriptions of the data class tables.
Category | Definition
--- | ---
Class Name | The name given to the class being described.
Class Type | The nature of the class. This is described as a "Container [...]" or "Abstract Container [...]". The value of "..." being (see Appendix A1.1 for the meaning of these values): "DerivedType" "List" "Selection" "Sequence" "Union" "Unordered" If the container is also marked as "Mixed" then the children are permitted to include text as well as attributes.
Parents | This is the list of classes that contain the class being described as either the type of a child characteristic or attribute. In the case of a Root Class the entry is also labelled as "Root Class".
Derived Classes | The set of classes that are derived from this class (there may be none). The entries are linked to the corresponding class descriptions.
Super Classes | The set of super classes from which the class being described is derived (there may be none). The entries are linked to the corresponding class descriptions.
Characteristics | Lists the set of characteristics for this class. The list of characteristics includes those that are inherited. Each characteristic is linked to the corresponding characteristic description table.
Children | Lists the set of attributes for this class (the only other permitted associations are generalizations). The list of children includes those attributes that are inherited. Each child entry is linked to the corresponding attribute description table. The nature of the relationship between the children is defined by the stereotype of the parent class i.e. the class type. If the child is in italics this denotes a reference to an abstract class and that an instance would NOT contain a child of that name but would be replaced by a complex set of children as defined by the associated abstract class.
Description | Contains descriptions relating to the class and its properties and relationships.

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### A1.3 Attribute and Characteristic Descriptions

Table A1.3 provides the key to the descriptions of the data attributes/characteristics for the data classes.

Table A1.3 The key to the descriptions of the data attribute/characteristic tables.
Category | Definition
--- | ---
Attribute Name or Characteristic Name | The name given to the attribute or characteristic being described. If the name is in italics this denotes an abstract attribute or characteristic.
Data Type | This is the data-type of the attribute or characteristic (if this is in italics it denotes an abstract class). The data-type can take many forms: Class Name - the name of the Class (this is linked to the class definition elsewhere in this document); Primitive Data-types from:- AnyTypeLax - the namespace data-type i.e. defining data from any context (this is used for allowing any form of extension); AnyURI - the AnyURI data-type (absolute or relatve URI); Base - the base data-type for defining a base URI/URL link reference; Boolean - the boolean data-type (with permitted values of "true" and "false"); Date - the date data-type (using the ISO 8601 format); DateTime - the date/time data-type (using the ISO 8601 format); Double - the double data-type (double precision floating point number - 64bit); Empty - the associated instance must be empty; ID - the unique identifier data-type; IDREF - the reference to a previously defined unique identifier data-type (ID); IDREFS - a list, whitespace separated, of references to a previously defined unique identifier data-type (ID); Int - the int data-type (this is derived from the "decimal" data-type); Integer - the integer data-type (using the); Language - the language data-type as defined in [RFC 3066]; Namespace - the namespace data-type i.e. defining data from a context other than that as the default for the data model (this is used for importing other data models); NamespaceLax - the namespace data-type i.e. defining data from a context other than that as the default for the data model (this is used for importing other data models but being lax on the validation); NonNegativeInteger - the non-negative integer data-type (this is derived from the "integer" data-type) i.e. an integer that is zero or higher; NCName - the NCName data-type (derived from the Name data-type); NormalizedString - the normalized string data type (strings with line feeds, carriage returns and tab characters removed); String - the normalized string data type.
Value Space | The range of valid values for this attribute/characteristic (including any default value). If the value space is unspecified, it is not known or is not important. This value space must be defined in terms of the associated data-type.
Scope | This is the scope of the attribute/characteristic with permitted values of: Local - denoted by "-" and meaning the attribute/characteristic has significance and access within the context of the parent class only; Global - denoted by "+" and meaning that the attribute/characteristic has global scoping (so must have a unique name) and can be accessed from anywhere.
Multiplicity | A property of an attribute/characteristic indicating the number of times it may be used or appear in a given class instance. The values of this property are expressed as a range or shorthand for a range using the notation: "0..1" [optional; restricted] "0..*" [optional; unrestricted] "1" [mandatory; restricted] "1..*" [mandatory; unrestricted]
Description | Contains descriptions relating to the attribute/characteristic and its values space.

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### A1.4 Enumerated Vocabulary Descriptions

Table A1.4 provides the key to the descriptions of the enumerated vocabulary classes. These are vocabularies that will be contained within the binding form itself

Table A1.4 The key to the descriptions of the enumerated vocabulary tables.
Category | Definition
--- | ---
Term | The vocabulary token itself i.e. the vocabulary entry.
Definition | The meaning of the term and how it should be used.

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### A1.5 External Vocabulary Descriptions

Table A1.5 provides the key to the descriptions of the external vocabulary classes. These are vocabularies that will be contained in some independent format e.g. using the IMS VDEX.

Table A1.5 The key to the descriptions of the external vocabulary tables.
Category | Definition
--- | ---
Term | The vocabulary token itself i.e. the vocabulary entry.
Definition | The meaning of the term and how it should be used. This consists of the "Caption" and "Description" of the vocabulary term. The caption is used to provide a human readable label for the term.

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### A1.6 Import Class Descriptions

Table A1.6 provides the key to the descriptions of the import classes.

Table A1.6 The key to the descriptions of the imported class tables.
Category | Definition
--- | ---
Import Class Name | The name of the class.
Parent Classes | The list of parent classes, and the associated children, that use this imported class. Each class and attribute name has a link to its corresponding tabular description in the information model.
Description | The description of how the class is used within the data model.

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# Appendix B XSD Binding Terms

## B1 XSD Binding Description Terms

### B1.1 UML/XSD Attribute Mapping Table Definition

Table B1.1 provides the key to the descriptions of UML to XSD attribute mapping tables.

Table B1.1 The key to the descriptions of UML to XSD attribute mapping tables.
Feature | Definition and Usage
--- | ---
Attribute Name | The name of the attribute (these are the attributes listed in the class identified by the « Roots » stereotype).
UML Class | The name of the class, the type of the attribute, in the UML diagrams (each class will have an associated stereotype label to denote its modelling interpretation). If the information model description is contained within the same document, this value is hot-linked to that description.
XSD Name | The equivalent name of the UML attribute name in the XSD i.e. the XML element name.
XSD Type | The XSD type - this will always be "Element".
XSD Data Type | The data-type in the context of the XSD. This is hot-linked to the corresponding description table in the binding.

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### B1.2 UML/XSD Class Mapping Table Definition

Table B1.2 provides the key to the descriptions of UML to XSD class mapping tables. This table shows the relationship between the two modelling components:

- Information model aspects - the name/type/multiplicity of the artefact in the information model
- Binding aspects - the corresponding name/type in the XSD binding

Table B1.2 The key to the descriptions of UML to XSD class mapping tables.
Feature | Definition and Usage
--- | ---
Name | The name of the UML class and the associated set of attributes and characteristics. The first row is used to describe the UML class. Camel-case is used for the attribute and characteristic names.
UML Artefact | The UML Class will be denoted as "Root", "Core" or "Derived" depending on the nature of the class. The list of attributes (mapped to XML elements) and characteristics (mapped to XML attributes) will be identified as either "Attributes" or "Characteristics".
Data Type | The data-type has several permitted values: PT:... - denotes a primitive type with "..." replaced by the actual primitiveType name DT:... (PT:...) - denotes a derived type of name "..." derived from the primitive type "PT:..." [Enumeration(...)] - denotes an enumeration of name "..." [List(...)] - denotes a list of the name "..." [Union(...)] - denotes a union of one or more data-types with the name "..." [Imported(...)] - denotes a class with the name "..." has been imported from another specification "Container[...]" - denotes a class of stereotype "..."
Multiplicity | The multiplicity of the child attribute/characteristic. The value for the Class itself is "-N/A-". The multiplicity values are: "0..1" [optional; restricted] "0..*" [optional; unrestricted] "1" [mandatory; restricted] "1..*" [mandatory; unrestricted] The multiplicity will also indicate when groups of elements have variable multiplicity. In the case when a selection between groups of elements is used then this is denoted by "XOR" being displayed above the multiplicity for each of the grouped elements. Alongside the XOR is the multiplicity of the group as a whole.
XSD Name | This is the equivalent name of the UML artefact in the XSD. In the case of a "Derived" class the UML attribute may be used to define constraints on the primitiveType and so may not have visibility in an instance. In this case the name entry will be "[ No XML instance visibility ]".
XSD Type | The XSD data-type. For the Class this will have either the value "ComplexType" or "SimpleType" or the statement "There is no equivalent derived complexType. This is a logical class that is used to identify a namespace constraint.". For the attributes the value is either "Element (Global)" or "Element (Local)" depending on the scoping. For the characteristics the value is either "Attribute (Global)" or "Attribute (Local)" depending on the scoping. In the case of a "Derived" class the UML attribute may be used to define constraints on the primitiveType and so may not have visibility in an instance. In this case the type entry will denote the type of restriction i.e. MinLength, MaxLength, WhiteSpace, MinInclusive, MaxInclusive and Pattern.

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### B1.3 UML/XSD Enumerated and Enumerated List Class Mapping Table Definition

Table B1.3 provides the key to the descriptions of UML to XSD enumerated and enumerated list class mapping tables.

Table B1.3 The key to the descriptions of UML to XSD enumerated and enumerated list class mapping tables.
Feature | Definition and Usage
--- | ---
Enumeration Class Name or Enumeration List Class Name | The name of the enumeration class or the enumeration list class.
Description | The list of permitted tokens for the enumeration or list. Each value is separated by the "|" character.

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### B1.4 UML/XSD List and Union Class Mapping Table Definition

Table B1.4 provides the key to the descriptions of UML to XSD list and union class mapping tables.

Table B1.4 The key to the descriptions of UML to XSD list and union class mapping tables.
Feature | Definition and Usage
--- | ---
List/Union Class Name | The name of the list or union class.
Description | The list of primitive types and simple derived types from which the list of values can be derived. Links to the definition of the description of the primitive and derived types provided elsewhere in the UML/XSD mapping are supplied.

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### B1.5 UML/XSD Primitive Types Mapping Table Definition

Table B1.5 provides the key to the descriptions of UML to XSD primitive-type mapping tables.

Table B1.5 The key to the descriptions of UML to XSD primitive mapping tables.
Feature | Definition and Usage
--- | ---
Primitive Type Name | The name of the primitve type used in the specification. Links to the definition of the primitive types, if provided elsewhere in the document, are supplied.
Description | The equivalent XML base data type that is used in the XSD binding.

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### B1.6 XSD Description for an Element

Table B1.6 provides the key to the descriptions of XSD element tables.

Table B1.6 The key to the descriptions of XSD element tables.
Feature | Definition and Usage
--- | ---
Namespace | The namespace for the XSD element.
Diagram | This diagram consists of three types of linked blocks. Straight link lines denote XML sequence whereas diagonal lines denote XML selection/unordered. The block forms are: Element Blocks - blue and grey shaded rounded rectangles containing the name of the element, its data-type, any default value and the multiplicity (denoted by a circle containing either the symbol "?", "1", "*", "+" or "U" representing optional, required, optionally many, at least one or unordered respectively. Unordered makes use of an associated set of Schematron Rules). If the element inherits features from another class then it contains a purple shadow that names the complexType from which the elements/attributes are inherited; Attribute Blocks - orange and grey shaded rounded rectangles containing the name of the attribute, its data-type, any default value and the multiplicity (denoted by a circle containing either the symbol "?" or "1" representing option or required respectively); Attribute Group Blocks - orange shaded rounded rectangle containing the name of the attribute group; Purple Surrounds - a surround on the attributes block denotes inherited attributes and a surround on the element block denotes inherited elements.
Type | The data-type for the element. This will possible entries are: The name of the primitiveType data-type Statement of an enumeration The import class name written as [Import (...)] The actual data-type with a link to the corresponding declaration.
Type Hierachy | The identification of the superclass upon which this type is based (the superclass is shown on the top line). This indicates the source of the inherited set of XML elements and attributes for the element.
Properties | The set of properties for the element including (these will not be shown for Global elements): Content - the type of content i.e "simple" or "complex" Mixed - whether or not the content is a mixture of content/element {true, false} MinOccurs - the minimum number of occurences MaxOccurs - the maximum number of occurences
Used by | The features in the XSD that make use of this global or root element. These features are listed under the heading "ComplexTypes". Each of the entries is linked to its formal description table.
Facets | The permitted set of facets for the content i.e. the ways in which the content is further constrained. This row is only present if there are associated facets. The set of permitted facets are: Enumeration - a permitted value MinLength - the required minimum number of characters MaxLength - the maximum number of characters WhiteSpace - default handling of white-space i.e. preserve or replace or collapse MinInclusive - the permitted minimum value (inclusive) MaxInclusive - the permitted maximum value (inclusive) Pattern - the permitted character set defined as a regular expression
Model | The set of child elements. This is an ordered list of elements (as per the sequence in the data-type complexType) and accompanied by their multiplicity. Links to the corresponding declarations are supplied. In the case where the type is an enumeration or primitiveType then the value is "N/A". The value may also be "Empty" to indicate that no children are permitted. If the element is imported i.e. from an external XSD, only the URL for that XSD will be given.
Attributes | The set of global and local XML attributes for this complexType (if the element is imported i.e. from an external XSD, only the URL for that XSD will be given). Links are made to the associated tabular definitions. Each attribute is described by: QName - the name with a link to the corresponding table description Type - the data-type Inherited - Yes/No statement of whether or not this attribute is inherited from a base complexType Scope - the scope defined as either "Local" or "Global" Use - the multiplicity as either "Required" or "Optional" Default - the default value or a "-" if there is none
Schematron Rules | The set of schematron rules to be applied for the element grouped as: Unordered Class - the Schematron Rules that enforce the "Unordered" stereotype; NS Constraint - the Schematron Rules that enforce the constraints on extension XML attributes; Explicit Rules - the Schematron Rules that enforce the explicitly defined constraints for the information model.
Source | The equivalent XSD code for the declaration of the element. This includes the multiplicity and default values for the element. See the W3C XSD documentation for the description of the permitted contents for this declaration. If the element is imported i.e. from an external XSD, only the URL for that XSD will be given.

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### B1.7 XSD Description for a Complex Type

Table B1.7 provides the key to the descriptions of XSD complex type tables.

Table B1.7 The key to the descriptions of XSD complex type tables.
Feature | Definition and Usage
--- | ---
Namespace | The namespace for the XSD complexType.
Annotations | The documentation comment for the data-type (the comment within the XSD).
Diagram | This diagram consists of four types of linked blocks. Straight link lines denote XML sequence whereas diagonal lines denote XML selection/unordered. The block forms are: ComplexType Block - a purple and grey shaded rectangle containing the name of the complexType and identification of whether it is abstract and supports mixed content; Element Blocks - blue and grey shaded rounded rectangles containing the name of the element, its data-type, any default value and the multiplicity (denoted by a circle containing either the symbol "?", "1", "*", "+" or "U" representing optional, required, optionally many, at least one or unordered respectively. Unordered makes use of an associated set of Schematron Rules); Attribute Blocks - orange and grey shaded rounded rectangles containing the name of the attribute, its data-type, any default value and the multiplicity (denoted by a circle containing either the symbol "?" or "1" representing option or required respectively); Attribute Group Blocks - orange shaded rounded rectangle containing the name of the attribute group; Purple Surrounds - a surround on the attributes block denotes inherited attributes and a surround on the element block denotes inherited elements.
Properties | The properties of the class expressed in terms of whether or not the complexType is abstract {true, false} or whether it supports mixed content {true, false}.
Facets | The permitted set of facets for the content i.e. the ways in which the content is further constrained. This row is only present if there are associated facets. The set of permitted facets are: Enumeration - a permitted value MinLength - the required minimum number of characters MaxLength - the maximum number of characters WhiteSpace - default handling of white-space i.e. preserve or replace or collapse MinInclusive - the permitted minimum value (inclusive) MaxInclusive - the permitted maximum value (inclusive) Pattern - the permitted character set defined as a regular expression
Used by | The features in the XSD that make use of this complexType. These features are listed under the headings "Root Elements", "Elements" and "ComplexTypes". Each of the entries is linked to its formal description table.
Model | The set of child elements. This is an ordered list of elements (as per the sequence in the complexType) and accompanied by their multiplicity. Links to the corresponding declarations are supplied. In the case where the type is an enumeration or primitiveType then the value is "N/A". The value may also be "Empty" to indicate that no children are permitted. In some situations the value may be "None" denoting that there are no children defined e.g. for a base class from which other classes are derived and which may have children as part of the extension.
Attributes | The set of global and local XML attributes for this complexType. Links are made to the associated tabular definitions. Each attribute is described by: QName - the name with a link to the corresponding table description Type - the data-type Inherited - Yes/No statement of whether or not this attribute is inherited from a base complexType Scope - the scope defined as either "Local" or "Global" Use - the multiplicity as either "Required" or "Optional" Default - the default value or a "-" if there is none
Schematron Rules | The set of schematron rules to be applied for the class grouped as: Unordered Class - the Schematron Rules that enforce the "Unordered" stereotype; NS Constraint - the Schematron Rules that enforce the constraints on extension XML attributes; Explicit Rules - the Schematron Rules that enforce the explicitly defined constraints for the information model.
Source | The equivalent XSD code for the declaration of the complexType. This is the full declaration. See the W3C XSD documentation for the description of the permitted contents for this declaration.

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### B1.8 XSD Description for a Simple Type

Table B1.8 provides the key to the descriptions of XSD simple type tables.

Table B1.8 The key to the descriptions of XSD simple type tables.
Feature | Definition and Usage
--- | ---
Namespace | The namespace for the XSD simpleType.
Diagram | This diagram consists of a single block. The block form is: SimpleType Block - a green and grey shaded rectangle containing the name of the simpleType and its data-type
Type | The data-type for the element. This is either a primitiveType or an enumeration.
Facets | The permitted set of facets for the content i.e. the ways in which the content is further constrained. This row is only present if there are associated facets. The set of permitted facets are: Enumeration - a permitted value MinLength - the required minimum number of characters MaxLength - the maximum number of characters WhiteSpace - default handling of white-space i.e. preserve or replace or collapse MinInclusive - the permitted minimum value (inclusive) MaxInclusive - the permitted maximum value (inclusive) Pattern - the permitted character set defined as a regular expression
Used by | The features in the XSD that make use of this simpleType. These features are listed under the headings "Attributes", "Elements" and "ComplexTypes". Each of the entries is linked to its formal description table.
Source | The equivalent XSD code for the declaration of the simpleType. This is the full declaration. See the W3C XSD documentation for the description of the permitted contents for this declaration.

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### B1.9 XSD Description for an Attribute Group

Table B1.9 provides the key to the descriptions of XSD attribute group tables.

Table B1.9 The key to the descriptions of XSD attribute group tables.
Feature | Definition and Usage
--- | ---
Namespace | The namespace for the XSD attribute group.
Diagram | This diagram consists of two types of linked blocks: Attribute Group Block - an orange shaded rectangle containing the name of the attribute group Attribute Blocks - an orange and grey shaded rectangle containing the name of the attribute, its data-type, any default value and the multiplicity (denoted by a circle containing either the symbol "?" or "1" representing optional or required respectively)
Used by | The features in the XSD that make use of this attributeGroup. These features are listed under the heading "ComplexTypes". Each of the entries is linked to its formal description table.
Attributes | The set of XML attributes that constitute the attributeGroup. This includes the data-type and multiplicity.
Schematron Rules | The set of schematron rules to be applied for the attributeGroup are: NS Constraint - the Schematron Rules that enforce the constraints on extension XML attributes; Explicit Rules - the Schematron Rules that enforce the explicitly defined constraints for the information model.
Source | The equivalent XSD code for the declaration of the attributeGroup. See the W3C XSD documentation for the description of the permitted contents for this declaration.

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### B1.10 XSD Description for an Attribute

Table B1.10 provides the key to the descriptions of XSD attribute tables.

Table B1.10 The key to the descriptions of XSD attribute tables.
Feature | Definition and Usage
--- | ---
Namespace | The namespace for the XSD attribute. Only external/imported attributes have a namespace.
Properties | The properties of the attributes expressed in terms of the multiplicity i.e. "Optional" or "Required" and the default value (not all attributes will have a default value).
Facets | The permitted set of facets for the content i.e. the ways in which the content is further constrained. This row is only present if there are associated facets. The set of permitted facets are: Enumeration - a permitted value MinLength - the required minimum number of characters MaxLength - the maximum number of characters WhiteSpace - default handling of white-space i.e. preserve or replace or collapse MinInclusive - the permitted minimum value (inclusive) MaxInclusive - the permitted maximum value (inclusive) Pattern - the permitted character set defined as a regular expression
Source | The equivalent XSD code for the declaration of the attribute. See the W3C XSD documentation for the description of the permitted contents for this declaration.

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### B1.11 VDEX Description for an External Vocabulary

Table B1.11 provides the key to the descriptions of VDEX tables.

Table B1.11 The key to the descriptions of VDEX vocabulary binding tables.
Feature | Definition
--- | ---
Name | The name/title for the vocabulary.
Identifier | The unique identifier the vocabulary.
Location | The Web location for the VDEX file.
Type | The type of vocabulary. The choise is "glossaryOrDictionary", "flatTokenTerms", "hierarchicalTokenTerms", "thesaurus" or "lax" (see the IMS VDEX Specification [VDEX, 04] for the use of these terms).
Publisher | The publisher of the vocabulary.
Keywords | The keywords for the vocabulary.
Terms | The set of terms that constitute the vocabulary. Each term there is defined by its: Name - the vocabulary name/token Status - the release status of the term either "Draft", "Provisional" or "Final" Caption - the human readable caption/label for the term Description - the meaning of the term

toc | top

# Appendix C XSD Listings

## C1 QTI Usage Data Statistics XSD Listing

The XSD listing is shown below (the XSD is available at: http://www.imsglobal.org/xsd/qti/qtiv2p2/imsqti_usagedata_v2p2.xsd).

    <?xml version = "1.0" encoding = "UTF-8"?>
    <xs:schema xmlns="http://www.imsglobal.org/xsd/imsqti_usagedata_v2p2"
         targetNamespace="http://www.imsglobal.org/xsd/imsqti_usagedata_v2p2"
         xmlns:xs="http://www.w3.org/2001/XMLSchema"
         version="IMS QTI USAGE 2.2.0"
         elementFormDefault="qualified"
         attributeFormDefault="unqualified">

        <xs:annotation>
            <xs:documentation>
                XSD Data File Information
                =========================
                Author:         Colin Smythe (IMS Global, UK) and Mark McKell (IMS Global, USA)
                Date:           1st September, 2015
                Version:        2.2
                Status:         Final Release
                Description:    This is the Platform Specific Model of the Usage Data in the IMS QTI v2.2 Specification Information Model. Is is this representation that is used to produce the XSD binding for the IMS QTI v2.2 Usage Data XSD.

                History:        This version supercedes the full IMS QTI v2.1 specification.

                License:        IPR and Distribution Notices

                                This machine readable file is derived from IMS Global specification IMS Question and Test Interoperability (QTI) Version 2.2
                                found at http://www.imsglobal.org/question and the original IMS Global schema binding or code base
                                http://www.imsglobal.org/question.

                                Recipients of this document are requested to submit, with their comments, notification of any relevant
                                patent claims or other intellectual property rights of which they may be aware that might be infringed by
                                any implementation of the specification set forth in this document, and to provide supporting documentation.

                                IMS takes no position regarding the validity or scope of any intellectual property or other rights that might
                                be claimed to pertain to the implementation or use of the technology described in this document or the extent
                                to which any license under such rights might or might not be available; neither does it represent that it has
                                made any effort to identify any such rights. Information on IMS procedures with respect to rights in IMS
                                specifications can be found at the IMS Global Intellectual Property Rights web page: http://www.imsglobal.org/ipr/imsipr_policyFinal.pdf.

                                Copyright (c) IMS Global Learning Consortium 1999-2016. All Rights Reserved.

                                Use of this specification to develop products or services is governed by the license with IMS found on the IMS website: http://www.imsglobal.org/license.html.

                                Permission is granted to all parties to use excerpts from this document as needed in producing requests for proposals.

                                The limited permissions granted above are perpetual and will not be revoked by IMS or its successors or assigns.

                                THIS SPECIFICATION IS BEING OFFERED WITHOUT ANY WARRANTY WHATSOEVER, AND IN PARTICULAR, ANY WARRANTY OF NONINFRINGEMENT IS
                                EXPRESSLY DISCLAIMED. ANY USE OF THIS SPECIFICATION SHALL BE MADE ENTIRELY AT THE IMPLEMENTERS OWN RISK, AND NEITHER THE CONSORTIUM
                                NOR ANY OF ITS MEMBERS OR SUBMITTERS, SHALL HAVE ANY LIABILITY WHATSOEVER TO ANY IMPLEMENTER OR THIRD PARTY FOR ANY DAMAGES OF
                                ANY NATURE WHATSOEVER, DIRECTLY OR INDIRECTLY, ARISING FROM THE USE OF THIS SPECIFICATION.

                Source UML File Information
                ===========================
                The source file information must be supplied as an XMI file (without diagram layout information).
                The supported UML authoring tools are:
                (a) Poseidon - v6 (and later)
                (b) Papyrus - v1.1.3 (and later)

                Source XSLT File Information
                ============================
                XSL Generator:    Specificationv1p0_GenerationToolv1.xsl
                XSLT Processor:   Saxon-EE-9.6.0.7
                Release:          1.0
                Date:             31st January, 2016
                Autogen Engineer: Colin Smythe (IMS Global, UK)
                Autogen Date:     2016-07-04

                IMS Global Auto-generation Binding Tool-kit (I-BAT)
                ===================================================
                This file was auto-generated using the IMS Global Binding Auto-generation Tool-kit (I-BAT).  While every
                attempt has been made to ensure that this tool auto-generates the files correctly, users should be aware
                that this is an experimental tool.  Permission is given to make use of this tool.  IMS Global makes no
                claim on the materials created by third party users of this tool.  Details on how to use this tool
                are contained in the IMS Global "I-BAT" documentation available at the IMS Global web-site:
                http://www.imsglobal.org.

                Tool Copyright:  2012-2016  (c) IMS Global Learning Consortium Inc.  All Rights Reserved.
            </xs:documentation>
        </xs:annotation>

        <!-- Generate Global Attributes (non-assigned) ******************************************************** -->

        <!-- ================================================================================================== -->

        <!-- Generate Global Attributes *********************************************************************** -->

        <!-- ================================================================================================== -->

        <!-- Generate Global List Types *********************************************************************** -->

        <!-- ================================================================================================== -->

        <!-- Generate Namespaced extension Group  ************************************************************* -->

        <!-- ================================================================================================== -->

        <!-- Generate Special DataTypes  ********************************************************************** -->

        <xs:complexType name="EmptyPrimitiveType.Type">
            <xs:complexContent>
                <xs:restriction base="xs:anyType" />
            </xs:complexContent>
        </xs:complexType>

        <!-- ================================================================================================== -->

        <!-- Generate the enumerated simpleType declarations ************************************************** -->

        <!-- ================================================================================================== -->

        <!-- Generate the simpleType elements based on IMS data-types (Parameter) ***************************** -->

        <!-- ================================================================================================== -->

        <!-- Generate the simpleType elements based on IMS data-types (Derived) ******************************* -->

        <!-- ================================================================================================== -->

        <!-- Generate the simpleType elements based on IMS data-types (Union) ********************************* -->

        <!-- ================================================================================================== -->

        <!-- Generate the simpleType elements based on IMS data-types (Complex) ******************************* -->

        <!-- ================================================================================================== -->

        <!-- Generate the derived data-type elements based upon simpleType ************************************ -->

        <xs:simpleType name="Date.Type">
            <xs:restriction base="xs:date">
                <xs:pattern value="[0-9]{4}-[0-9]{2}-[0-9]{2}" />
            </xs:restriction>
        </xs:simpleType>

        <xs:simpleType name="Identifier.Type">
            <xs:restriction base="xs:NCName" />
        </xs:simpleType>

        <!-- ================================================================================================== -->

        <!-- Generate the derived data-type elements based upon derived simpleType **************************** -->

        <!-- ================================================================================================== -->

        <!-- Generate the ComplexTypes ************************************************************************ -->

        <xs:complexType name="CategorizedStatistic.Type" abstract="false" mixed="false">
            <xs:annotation>
                <xs:documentation source="documentation">
                    An item statistic that consists of multiple values, e.g. IRT Dispersion Parameters.
                </xs:documentation>
            </xs:annotation>
            <xs:sequence>
                <xs:element name="targetObject" type="TargetObject.Type" minOccurs="1" maxOccurs="unbounded" />
                <xs:element name="mapping" type="Mapping.Type" minOccurs="1" maxOccurs="1" />
            </xs:sequence>
            <xs:attribute name="name" use="required" type="Identifier.Type" />
            <xs:attribute name="glossary" use="optional" type="xs:anyURI" />
            <xs:attribute name="context" use="required" type="xs:anyURI" />
            <xs:attribute name="caseCount" use="optional" type="xs:integer" />
            <xs:attribute name="stdError" use="optional" type="xs:double" />
            <xs:attribute name="stdDeviation" use="optional" type="xs:double" />
            <xs:attribute name="lastUpdated" use="optional" type="Date.Type" />
        </xs:complexType>

        <xs:complexType name="Mapping.Type" abstract="false" mixed="false">
            <xs:annotation>
                <xs:documentation source="documentation">
                    A special class used to create a mapping from a source set of any baseType (except file a-
                    nd duration) to a single float. Note that mappings from values of base type float should
                    be avoided due to the difficulty of matching floating point values, see the match operator
                    for more details. When mapping containers the result is the sum of the mapped values from
                    the target set. See mapResponse for details.
                </xs:documentation>
            </xs:annotation>
            <xs:sequence>
                <xs:element name="mapEntry" type="MapEntry.Type" minOccurs="1" maxOccurs="unbounded" />
            </xs:sequence>
            <xs:attribute name="lowerBound" use="optional" type="xs:double" />
            <xs:attribute name="upperBound" use="optional" type="xs:double" />
            <xs:attribute name="defaultValue" use="optional" default="0" type="xs:double" />
        </xs:complexType>

        <xs:complexType name="OrdinaryStatistic.Type" abstract="false" mixed="false">
            <xs:annotation>
                <xs:documentation source="documentation">
                    An item statistic that consists of a single numeric value.
                </xs:documentation>
            </xs:annotation>
            <xs:sequence>
                <xs:element name="targetObject" type="TargetObject.Type" minOccurs="1" maxOccurs="unbounded" />
                <xs:element name="value" type="Value.Type" minOccurs="1" maxOccurs="1" />
            </xs:sequence>
            <xs:attribute name="name" use="required" type="Identifier.Type" />
            <xs:attribute name="glossary" use="optional" type="xs:anyURI" />
            <xs:attribute name="context" use="required" type="xs:anyURI" />
            <xs:attribute name="caseCount" use="optional" type="xs:integer" />
            <xs:attribute name="stdError" use="optional" type="xs:double" />
            <xs:attribute name="stdDeviation" use="optional" type="xs:double" />
            <xs:attribute name="lastUpdated" use="optional" type="Date.Type" />
        </xs:complexType>

        <xs:complexType name="UsageData.Type" abstract="false" mixed="false">
            <xs:annotation>
                <xs:documentation source="documentation">
                    Usage data, most commonly item statistics, do not form part of an assessmentItem directly
                    because they always relate to some context or domain in which the statistics are valid. T-
                    herefore, this specification defines a separate class for describing these statistics. Ea-
                    ch statistic refers to both its context and to the assessmentItem(s) it relates to. There-
                    fore, instances of this class are bound and packaged separately for interoperability.
                </xs:documentation>
            </xs:annotation>
            <xs:sequence>
                <xs:choice minOccurs="0" maxOccurs="unbounded">
                    <xs:element name="ordinaryStatistic" type="OrdinaryStatistic.Type" minOccurs="1" maxOccurs="1"/>
                    <xs:element name="categorizedStatistic" type="CategorizedStatistic.Type" minOccurs="1" maxOccurs="1"/>
                </xs:choice>
            </xs:sequence>
            <xs:attribute name="glossary" use="optional" type="xs:anyURI" />
        </xs:complexType>

        <!-- ================================================================================================== -->

        <!-- Generate the SOAP Binding ComplexTypes *********************************************************** -->

        <!-- ================================================================================================== -->

        <!-- Generate the derived ComplexTypes **************************************************************** -->

        <xs:complexType name="MapEntry.Type" abstract="false" mixed="false">
            <xs:annotation>
                <xs:documentation source="documentation">
                    A map is defined by a set of mapEntries, each of which maps a single value from the source
                    set onto a single float.
                </xs:documentation>
            </xs:annotation>
            <xs:complexContent>
                <xs:extension base="EmptyPrimitiveType.Type">
                    <xs:attribute name="mapKey" use="required" type="xs:normalizedString" />
                    <xs:attribute name="mappedValue" use="required" type="xs:double" />
                    <xs:attribute name="caseSensitive" use="optional" type="xs:boolean" />
                </xs:extension>
            </xs:complexContent>
        </xs:complexType>

        <xs:complexType name="TargetObject.Type" abstract="false" mixed="false">
            <xs:annotation>
                <xs:documentation source="documentation">
                    The targetObject is used to refer to an assessment object. This object may be an assessme-
                    ntItem or some other type of object defined outside the scope of this specification, for
                    example, an entire test. In some cases it is desirable to refer not just to the assessment
                    object but to a specific part of that object, in which case the optional partIdentifier c-
                    an be used.
                </xs:documentation>
            </xs:annotation>
            <xs:complexContent>
                <xs:extension base="EmptyPrimitiveType.Type">
                    <xs:attribute name="identifier" use="required" type="xs:string" />
                    <xs:attribute name="partIdentifier" use="optional" type="Identifier.Type" />
                </xs:extension>
            </xs:complexContent>
        </xs:complexType>

        <xs:complexType name="Value.Type" abstract="false" mixed="false">
            <xs:annotation>
                <xs:documentation source="documentation">
                    A class that can represent a single value of any baseType in variable declarations and re-
                    sult reports. The base-type is defined by the baseType attribute of the declaration except
                    in the case of variables with record cardinality.
                </xs:documentation>
            </xs:annotation>
            <xs:simpleContent>
                <xs:extension base="xs:normalizedString">
                    <xs:attribute name="fieldIdentifier" use="optional" type="Identifier.Type" />
                    <xs:attribute name="baseType" use="optional">
                        <xs:simpleType>
                            <xs:annotation>
                                <xs:documentation source="documentation">
                                    A base-type is simply a description of a set of atomic values (atomic to this specificati-
                                    on). Note that several of the baseTypes used to define the runtime data model have identi-
                                    cal definitions to those of the basic data types used to define the values for attributes
                                    in the specification itself. The use of an enumeration to define the set of baseTypes used
                                    in the runtime model, as opposed to the use of classes with similar names, is designed to
                                    help distinguish between these two distinct levels of modelling.
                                </xs:documentation>
                            </xs:annotation>
                            <xs:restriction base="xs:string">
                                <xs:enumeration value="boolean" />
                                <xs:enumeration value="directedPair" />
                                <xs:enumeration value="duration" />
                                <xs:enumeration value="file" />
                                <xs:enumeration value="float" />
                                <xs:enumeration value="identifier" />
                                <xs:enumeration value="integer" />
                                <xs:enumeration value="pair" />
                                <xs:enumeration value="point" />
                                <xs:enumeration value="string" />
                                <xs:enumeration value="uri" />
                            </xs:restriction>
                        </xs:simpleType>
                    </xs:attribute>
                </xs:extension>
            </xs:simpleContent>
        </xs:complexType>

        <!-- ================================================================================================== -->

        <!-- Declaration of the elements (Complex) ************************************************************ -->

        <!-- ================================================================================================== -->

        <!-- Declaration of the elements (Derived) ************************************************************ -->

        <!-- ================================================================================================== -->

        <!-- Declaration of the root element(s) *************************************************************** -->

        <xs:element name="usageData" type="UsageData.Type" />

        <!-- ================================================================================================== -->

    </xs:schema>

toc | top

# Appendix D VDEX Listings

## Appendix D1 "Distractor Statistics" Vocabulary Listing

The VDEX listing is shown below (the VDEX is available at: http://www.imsglobal.org/question/qtiv2p2/glossaries/distractorstatisticsglossaryv1p0.xml). A human-readable version of the VDEX is available at: http://www.imsglobal.org/question/qtiv2p2/glossaries/distractorstatisticsglossaryv1p0.html.

    <?xml version = "1.0" encoding = "UTF-8"?>

    <!-- ********************************************************************************************** -->
    <!--                                                                                                -->
    <!-- Author:         Colin Smythe (IMS Global, UK) and Mark McKell (IMS Global, USA)                -->
    <!-- Date:           2015-06-01                                                                     -->
    <!-- Version:        1.0                                                                            -->
    <!-- Status:         Final release                                                                  -->
    <!--                                                                                                -->
    <!-- Description:    The set of terms that would be used to collect distractor statistics. This is  -->
    <!--                 the value that will be entered in the 'name' element.                          -->
    <!--                 The set of terms in the vocabulary are:                                        -->
    <!--                 * AISResponse;                                                                 -->
    <!--                 * NumberChoosingResponse;                                                      -->
    <!--                 * PTbis-Response;                                                              -->
    <!--                 * ParentChoosingResponse;                                                      -->
    <!--                                                                                                -->
    <!-- History:        The first formal release of this QTI Glossary as part of QTIv2.2.              -->
    <!--                                                                                                -->
    <!-- Licenses:       IPR and Distribution Notices                                                   -->
    <!--                                                                                                -->
    <!--                 This machine readable vocabulary is derived from the IMS Global specification  -->
    <!--                 IMS Global Question and Test Interoperability (QTI) Version 2.2 found at http- -->
    <!--                 ://www.imsglobal.org/question and the original IMS Global schema binding or c- -->
    <!--                 ode base http://www.imsglobal.org/question.                                    -->
    <!--                                                                                                -->
    <!--                 Recipients of this document are requested to submit, with their comments, not- -->
    <!--                 ification of any relevant patent claims or other intellectual property rights  -->
    <!--                 of which they may be aware that might be infringed by any implementation of t- -->
    <!--                 he specification set forth in this document, and to provide supporting docume- -->
    <!--                 ntation.                                                                       -->
    <!--                                                                                                -->
    <!--                 IMS takes no position regarding the validity or scope of any intellectual pro- -->
    <!--                 perty or other rights that  might be claimed to pertain to the implementation  -->
    <!--                 or use of the technology described in this document or the extent to which any -->
    <!--                 license under such rights might or might not be  available; neither does it r- -->
    <!--                 epresent that it has made any effort to identify any such rights. Information  -->
    <!--                 on the IMS procedures with respect to rights in IMS specifications  can be fo- -->
    <!--                 und at the IMS Intellectual Property Rights web page: http://www.imsglobal.or- -->
    <!--                 g/ipr/imsipr_policyFinal.pdf.                                                  -->
    <!--                                                                                                -->
    <!--                 Copyright © IMS Global Learning Consortium 1999-2016. All Rights Reserved.     -->
    <!--                                                                                                -->
    <!--                 Use of this specification to develop products or services is governed by the   -->
    <!--                 license with IMS found on the IMS website: http://www.imsglobal.org/license.h- -->
    <!--                 tml.                                                                           -->
    <!--                                                                                                -->
    <!--                 Permission is granted to all parties to use excerpts from this document as ne- -->
    <!--                 eded in producing requests for proposals.                                      -->
    <!--                                                                                                -->
    <!--                 The limited permissions granted above are perpetual and will not be revoked by -->
    <!--                 IMS or its successors or assigns.                                              -->
    <!--                                                                                                -->
    <!--                 THIS SPECIFICATION IS BEING OFFERED WITHOUT ANY WARRANTY WHATSOEVER, AND IN P- -->
    <!--                 ARTICULAR,  ANY WARRANTY OF NONINFRINGEMENT IS EXPRESSLY DISCLAIMED. ANY USE   -->
    <!--                 OF THIS SPECIFICATION SHALL BE MADE ENTIRELY AT THE IMPLEMENTERS OWN RISK, AND -->
    <!--                 NEITHER THE  CONSORTIUM, NOR ANY OF ITS MEMBERS OR SUBMITTERS, SHALL HAVE ANY  -->
    <!--                 LIABILITY WHATSOEVER TO ANY IMPLEMENTER OR THIRD PARTY FOR ANY DAMAGES OF ANY  -->
    <!--                 NATURE WHATSOEVER,  DIRECTLY OR INDIRECTLY, ARISING FROM THE USE OF THIS SPEC- -->
    <!--                 IFICATION.                                                                     -->
    <!--                                                                                                -->
    <!-- Source XSLT File Information                                                                   -->
    <!-- ============================                                                                   -->
    <!-- XSL Generator:  Specificationv1p0_GenerationToolv1.xsl                                         -->
    <!-- XSLT Processor: Saxon-HE-9.4.0.4                                                               -->
    <!-- Release:        1.0                                                                            -->
    <!-- Date:           31st January, 2016                                                             -->
    <!-- Autogen Eng:    Colin Smythe (IMS Global, UK)                                                  -->
    <!-- Autogen Date:   2016-07-04                                                                     -->
    <!--                                                                                                -->
    <!-- Webster Auto-generation Toolkit                                                                -->
    <!-- ===============================                                                                -->
    <!-- This VDEX was auto-generated using the IMS Global Binding Auto-generation Toolkit (I-BAT). Wh- -->
    <!-- ile every attempt has been made to ensure that this tool auto-generates the VDEXs correctly,   -->
    <!-- users should be aware that this is an experimental tool. Permission is given to make use of t- -->
    <!-- his tool. IMS Global makes no claim on the materials created by third party users of this too- -->
    <!-- l. Details on how to use this auto-generation toolkit are available at the IMS Global web-sit- -->
    <!-- e: www.imsglobal.org.'                                                                         -->
    <!--                                                                                                -->
    <!-- Tool Copyright: 2005-2016 (c) IMS Global Learning Consortium Inc.  All Rights Reserved.        -->
    <!--                                                                                                -->
    <!-- $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ -->

    <vdex profileType="glossaryOrDictionary"
          xmlns="http://www.imsglobal.org/xsd/imsvdex_v1p0"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://www.imsglobal.org/xsd/imsvdex_v1p0 http://www.imsglobal.org/xsd/imsvdex_v1p0.xsd http://ltsc.ieee.org/xsd/LOM http://www.imsglobal.org/xsd/imsmd_loose_v1p3p2.xsd"
          orderSignificant="false"
          language="en-US">
        <vocabName>
            <langstring language="en-US">IMS Global QTI Glossary of Terms for Usage Data Distractor Statistics</langstring>
        </vocabName>
        <vocabIdentifier isRegistered="true">http://www.imsglobal.org/qti/qtiv2p2/distractorstatisticsglossaryv1p0</vocabIdentifier>
        <term>
            <termIdentifier>AISResponse</termIdentifier>
            <caption>
                <langstring language="en-US">Average Item Score for Response</langstring>
            </caption>
            <description>
                <langstring language="en-US">Equal to the mean of the item scores for the group of individuals that selected the response option.</langstring>
            </description>
            <metadata>
                <lom xmlns="http://ltsc.ieee.org/xsd/LOM">
                    <general>
                        <keyword>
                            <string>Distractor Statistics, AISResponse, IMS Global QTIv2.2</string>
                        </keyword>
                    </general>
                    <relation>
                        <resource>
                            <description>
                                <string>IMS Global</string>
                            </description>
                        </resource>
                    </relation>
                    <lifeCycle>
                        <contribute>
                            <role>
                                <value>publisher</value>
                            </role>
                            <entity>IMS Global Learning Consortium Inc.</entity>
                            <date>
                                <dateTime>2015-03-01</dateTime>
                            </date>
                        </contribute>
                        <status>
                            <value>Final</value>
                        </status>
                    </lifeCycle>
                </lom>
            </metadata>
        </term>
        <term>
            <termIdentifier>NumberChoosingResponse</termIdentifier>
            <caption>
                <langstring language="en-US">The number of people choosing a specified response or getting a specified code.</langstring>
            </caption>
            <description>
                <langstring language="en-US">Equal to the number of individuals that selected the response option. This can also be used for the number of individuals that received a certain rating on a judged item such as an essay question.</langstring>
            </description>
            <metadata>
                <lom xmlns="http://ltsc.ieee.org/xsd/LOM">
                    <general>
                        <keyword>
                            <string>Distractor Statistics, Number Choosing Response, IMS Global QTIv2.2</string>
                        </keyword>
                    </general>
                    <relation>
                        <resource>
                            <description>
                                <string>IMS Global</string>
                            </description>
                        </resource>
                    </relation>
                    <lifeCycle>
                        <contribute>
                            <role>
                                <value>publisher</value>
                            </role>
                            <entity>IMS Global Learning Consortium Inc.</entity>
                            <date>
                                <dateTime>2015-03-01</dateTime>
                            </date>
                        </contribute>
                        <status>
                            <value>Final</value>
                        </status>
                    </lifeCycle>
                </lom>
            </metadata>
        </term>
        <term>
            <termIdentifier>PTbis-Response</termIdentifier>
            <caption>
                <langstring language="en-US">r-pointbiserial for Response</langstring>
            </caption>
            <description>
                <langstring language="en-US">A group-dependent measure of the discrimination of the response option, the pointbiserial correlation between selection of the response option and a criterion such as the total score on the test.</langstring>
            </description>
            <metadata>
                <lom xmlns="http://ltsc.ieee.org/xsd/LOM">
                    <general>
                        <keyword>
                            <string>Distractor Statistics, PTbis-Response, IMS Global QTIv2.2</string>
                        </keyword>
                    </general>
                    <relation>
                        <resource>
                            <description>
                                <string>IMS Global</string>
                            </description>
                        </resource>
                    </relation>
                    <lifeCycle>
                        <contribute>
                            <role>
                                <value>publisher</value>
                            </role>
                            <entity>IMS Global Learning Consortium Inc.</entity>
                            <date>
                                <dateTime>2015-03-01</dateTime>
                            </date>
                        </contribute>
                        <status>
                            <value>Final</value>
                        </status>
                    </lifeCycle>
                </lom>
            </metadata>
        </term>
        <term>
            <termIdentifier>ParentChoosingResponse</termIdentifier>
            <caption>
                <langstring language="en-US">The percent of people choosing a specified response or getting a specified code.</langstring>
            </caption>
            <description>
                <langstring language="en-US">Equal to the percent of test takers that selected the response option. This can also be used for the percent of individuals that received a certain rating on a judged item such as an essay question.</langstring>
            </description>
            <metadata>
                <lom xmlns="http://ltsc.ieee.org/xsd/LOM">
                    <general>
                        <keyword>
                            <string>Distractor Statistics, Percent Choosing Response, IMS Global QTIv2.2</string>
                        </keyword>
                    </general>
                    <relation>
                        <resource>
                            <description>
                                <string>IMS Global</string>
                            </description>
                        </resource>
                    </relation>
                    <lifeCycle>
                        <contribute>
                            <role>
                                <value>publisher</value>
                            </role>
                            <entity>IMS Global Learning Consortium Inc.</entity>
                            <date>
                                <dateTime>2015-03-01</dateTime>
                            </date>
                        </contribute>
                        <status>
                            <value>Final</value>
                        </status>
                    </lifeCycle>
                </lom>
            </metadata>
        </term>
        <metadata>
            <lom xmlns="http://ltsc.ieee.org/xsd/LOM">
                <general>
                    <title>
                        <string>IMS Global QTI Glossary of Terms for Usage Data Distractor Statistics</string>
                    </title>
                    <keyword>
                        <string>QTIv2.2, Usage Data, Distractor Statistics Glossary</string>
                    </keyword>
                    <language>en-US</language>
                    <description>
                        <string>Description: The set of terms that would be used to collect distractor statistics. This is the value that will be entered in the 'name' element.</string>
                        <string>History: The first formal release of this QTI Glossary as part of QTIv2.2.</string>
                    </description>
                </general>
                <lifeCycle>
                    <contribute>
                        <role>
                            <value>author</value>
                        </role>
                        <entity>Colin Smythe (IMS Global, UK) and Mark McKell (IMS Global, USA)</entity>
                    </contribute>
                    <version>
                        <string>1.0</string>
                    </version>
                    <status>
                        <value>Final release</value>
                    </status>
                    <contribute>
                        <role>
                            <value>publisher</value>
                        </role>
                        <entity>IMS Global Learning Consortium Inc.</entity>
                        <date>
                            <dateTime>2015-06-01</dateTime>
                        </date>
                    </contribute>
                </lifeCycle>
                <rights>
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                        <value>yes</value>
                    </copyrightAndOtherRestrictions>
                    <description>
                        <string>2015 (c) IMS Global Learning Consortium Inc.</string>
                    </description>
                </rights>
                <technical>
                    <format>XML</format>
                </technical>
            </lom>
        </metadata>
    </vdex>

## Appendix D2 "Item Statistics" Vocabulary Listing

The VDEX listing is shown below (the VDEX is available at: http://www.imsglobal.org/question/qtiv2p2/glossaries/itemstatisticsglossaryv1p0.xml). A human-readable version of the VDEX is available at: http://www.imsglobal.org/question/qtiv2p2/glossaries/itemstatisticsglossaryv1p0.html.

    <?xml version = "1.0" encoding = "UTF-8"?>

    <!-- ********************************************************************************************** -->
    <!--                                                                                                -->
    <!-- Author:         Colin Smythe (IMS Global, UK) and Mark McKell (IMS Global, USA)                -->
    <!-- Date:           2015-06-01                                                                     -->
    <!-- Version:        1.0                                                                            -->
    <!-- Status:         Final Release                                                                  -->
    <!--                                                                                                -->
    <!-- Description:    The set of terms that would be used to collect the item statistics. This is t- -->
    <!--                 he value that will be entered in the 'name' element.                           -->
    <!--                 The set of terms in the vocabulary are:                                        -->
    <!--                 * A-Param;                                                                     -->
    <!--                 * AIS;                                                                         -->
    <!--                 * B-Param;                                                                     -->
    <!--                 * C-Param;                                                                     -->
    <!--                 * D-Param;                                                                     -->
    <!--                 * Fifths_Table_Highest;                                                        -->
    <!--                 * Fifths_Table_Lowest;                                                         -->
    <!--                 * Fifths_Table_Middle;                                                         -->
    <!--                 * Fifths_Table_Second_Highest;                                                 -->
    <!--                 * Fifths_Table_Second_Lowest;                                                  -->
    <!--                 * P-value;                                                                     -->
    <!--                 * PHI;                                                                         -->
    <!--                 * PTbis;                                                                       -->
    <!--                 * Polyserial;                                                                  -->
    <!--                 * Score_Conversion;                                                            -->
    <!--                 * rbis;                                                                        -->
    <!--                                                                                                -->
    <!-- History:        The first formal release of this QTI Glossary as part of QTIv2.2.              -->
    <!--                                                                                                -->
    <!-- Licenses:       IPR and Distribution Notices                                                   -->
    <!--                                                                                                -->
    <!--                 This machine readable vocabulary is derived from the IMS Global specification  -->
    <!--                 IMS Global Question and Test Interoperability (QTI) Version 2.2 found at http- -->
    <!--                 ://www.imsglobal.org/question and the original IMS Global schema binding or c- -->
    <!--                 ode base http://www.imsglobal.org/question.                                    -->
    <!--                                                                                                -->
    <!--                 Recipients of this document are requested to submit, with their comments, not- -->
    <!--                 ification of any relevant patent claims or other intellectual property rights  -->
    <!--                 of which they may be aware that might be infringed by any implementation of t- -->
    <!--                 he specification set forth in this document, and to provide supporting docume- -->
    <!--                 ntation.                                                                       -->
    <!--                                                                                                -->
    <!--                 IMS takes no position regarding the validity or scope of any intellectual pro- -->
    <!--                 perty or other rights that  might be claimed to pertain to the implementation  -->
    <!--                 or use of the technology described in this document or the extent to which any -->
    <!--                 license under such rights might or might not be  available; neither does it r- -->
    <!--                 epresent that it has made any effort to identify any such rights. Information  -->
    <!--                 on the IMS procedures with respect to rights in IMS specifications  can be fo- -->
    <!--                 und at the IMS Intellectual Property Rights web page: http://www.imsglobal.or- -->
    <!--                 g/ipr/imsipr_policyFinal.pdf.                                                  -->
    <!--                                                                                                -->
    <!--                 Copyright © IMS Global Learning Consortium 1999-2016. All Rights Reserved.     -->
    <!--                                                                                                -->
    <!--                 Use of this specification to develop products or services is governed by the   -->
    <!--                 license with IMS found on the IMS website: http://www.imsglobal.org/license.h- -->
    <!--                 tml.                                                                           -->
    <!--                                                                                                -->
    <!--                 Permission is granted to all parties to use excerpts from this document as ne- -->
    <!--                 eded in producing requests for proposals.                                      -->
    <!--                                                                                                -->
    <!--                 The limited permissions granted above are perpetual and will not be revoked by -->
    <!--                 IMS or its successors or assigns.                                              -->
    <!--                                                                                                -->
    <!--                 THIS SPECIFICATION IS BEING OFFERED WITHOUT ANY WARRANTY WHATSOEVER, AND IN P- -->
    <!--                 ARTICULAR,  ANY WARRANTY OF NONINFRINGEMENT IS EXPRESSLY DISCLAIMED. ANY USE   -->
    <!--                 OF THIS SPECIFICATION SHALL BE MADE ENTIRELY AT THE IMPLEMENTERS OWN RISK, AND -->
    <!--                 NEITHER THE  CONSORTIUM, NOR ANY OF ITS MEMBERS OR SUBMITTERS, SHALL HAVE ANY  -->
    <!--                 LIABILITY WHATSOEVER TO ANY IMPLEMENTER OR THIRD PARTY FOR ANY DAMAGES OF ANY  -->
    <!--                 NATURE WHATSOEVER,  DIRECTLY OR INDIRECTLY, ARISING FROM THE USE OF THIS SPEC- -->
    <!--                 IFICATION.                                                                     -->
    <!--                                                                                                -->
    <!-- Source XSLT File Information                                                                   -->
    <!-- ============================                                                                   -->
    <!-- XSL Generator:  Specificationv1p0_GenerationToolv1.xsl                                         -->
    <!-- XSLT Processor: Saxon-HE-9.4.0.4                                                               -->
    <!-- Release:        1.0                                                                            -->
    <!-- Date:           31st January, 2016                                                             -->
    <!-- Autogen Eng:    Colin Smythe (IMS Global, UK)                                                  -->
    <!-- Autogen Date:   2016-07-04                                                                     -->
    <!--                                                                                                -->
    <!-- Webster Auto-generation Toolkit                                                                -->
    <!-- ===============================                                                                -->
    <!-- This VDEX was auto-generated using the IMS Global Binding Auto-generation Toolkit (I-BAT). Wh- -->
    <!-- ile every attempt has been made to ensure that this tool auto-generates the VDEXs correctly,   -->
    <!-- users should be aware that this is an experimental tool. Permission is given to make use of t- -->
    <!-- his tool. IMS Global makes no claim on the materials created by third party users of this too- -->
    <!-- l. Details on how to use this auto-generation toolkit are available at the IMS Global web-sit- -->
    <!-- e: www.imsglobal.org.'                                                                         -->
    <!--                                                                                                -->
    <!-- Tool Copyright: 2005-2016 (c) IMS Global Learning Consortium Inc.  All Rights Reserved.        -->
    <!--                                                                                                -->
    <!-- $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ -->

    <vdex profileType="glossaryOrDictionary"
          xmlns="http://www.imsglobal.org/xsd/imsvdex_v1p0"
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          xsi:schemaLocation="http://www.imsglobal.org/xsd/imsvdex_v1p0 http://www.imsglobal.org/xsd/imsvdex_v1p0.xsd http://ltsc.ieee.org/xsd/LOM http://www.imsglobal.org/xsd/imsmd_loose_v1p3p2.xsd"
          orderSignificant="false"
          language="en-US">
        <vocabName>
            <langstring language="en-US">IMS Global QTI Glossary of Terms for Usage Data Item Statistics</langstring>
        </vocabName>
        <vocabIdentifier isRegistered="true">http://www.imsglobal.org/qti/qtiv2p2/itemstatisticsglossaryv1p0</vocabIdentifier>
        <term>
            <termIdentifier>A-Param</termIdentifier>
            <caption>
                <langstring language="en-US">IRT a parameter</langstring>
            </caption>
            <description>
                <langstring language="en-US">Index of item discrimination based on item response theory.</langstring>
            </description>
            <metadata>
                <lom xmlns="http://ltsc.ieee.org/xsd/LOM">
                    <general>
                        <keyword>
                            <string>Item Statistics, A-Param, IMS Global QTIv2.2</string>
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                    </general>
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                            <description>
                                <string>IMS Global</string>
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                            </date>
                        </contribute>
                        <status>
                            <value>Final</value>
                        </status>
                    </lifeCycle>
                </lom>
            </metadata>
        </term>
        <term>
            <termIdentifier>AIS</termIdentifier>
            <caption>
                <langstring language="en-US">Average Item Score</langstring>
            </caption>
            <description>
                <langstring language="en-US">A group-dependent measure of item difficulty. Equal to the mean of the item scores for a group of individuals. For a rights-only dichotomously scored test, equivalent to the percent answering the item correctly (P-value).</langstring>
            </description>
            <metadata>
                <lom xmlns="http://ltsc.ieee.org/xsd/LOM">
                    <general>
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                            <string>Distractor Statistics, AIS, IMS Global QTIv2.2</string>
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                            </date>
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                        <status>
                            <value>Final</value>
                        </status>
                    </lifeCycle>
                </lom>
            </metadata>
        </term>
        <term>
            <termIdentifier>B-Param</termIdentifier>
            <caption>
                <langstring language="en-US">IRT b parameter</langstring>
            </caption>
            <description>
                <langstring language="en-US">Index of item difficulty based on item response theory.</langstring>
            </description>
            <metadata>
                <lom xmlns="http://ltsc.ieee.org/xsd/LOM">
                    <general>
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                            <string>Item Statistics, B-Param, IMS Global QTIv2.2</string>
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                            <description>
                                <string>IMS Global</string>
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                            <entity>IMS Global Learning Consortium Inc.</entity>
                            <date>
                                <dateTime>2015-03-01</dateTime>
                            </date>
                        </contribute>
                        <status>
                            <value>Final</value>
                        </status>
                    </lifeCycle>
                </lom>
            </metadata>
        </term>
        <term>
            <termIdentifier>C-Param</termIdentifier>
            <caption>
                <langstring language="en-US">IRT c parameter</langstring>
            </caption>
            <description>
                <langstring language="en-US">The lower asymptote of the item response function. Generally an index of guessing i.e. the probability of getting the item correct for very low ability examinees.</langstring>
            </description>
            <metadata>
                <lom xmlns="http://ltsc.ieee.org/xsd/LOM">
                    <general>
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                            <string>Item Statistics, C-Param, IMS Global QTIv2.2</string>
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                        <resource>
                            <description>
                                <string>IMS Global</string>
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                            <role>
                                <value>publisher</value>
                            </role>
                            <entity>IMS Global Learning Consortium Inc.</entity>
                            <date>
                                <dateTime>2015-03-01</dateTime>
                            </date>
                        </contribute>
                        <status>
                            <value>Final</value>
                        </status>
                    </lifeCycle>
                </lom>
            </metadata>
        </term>
        <term>
            <termIdentifier>D-Param</termIdentifier>
            <caption>
                <langstring language="en-US">IRT d parameter</langstring>
            </caption>
            <description>
                <langstring language="en-US">A measure of the dispersion of the item computed using the IRT method.</langstring>
            </description>
            <metadata>
                <lom xmlns="http://ltsc.ieee.org/xsd/LOM">
                    <general>
                        <keyword>
                            <string>Item Statistics, D-Param, IMS Global QTIv2.2</string>
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                        <resource>
                            <description>
                                <string>IMS Global</string>
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                        <contribute>
                            <role>
                                <value>publisher</value>
                            </role>
                            <entity>IMS Global Learning Consortium Inc.</entity>
                            <date>
                                <dateTime>2015-03-01</dateTime>
                            </date>
                        </contribute>
                        <status>
                            <value>Final</value>
                        </status>
                    </lifeCycle>
                </lom>
            </metadata>
        </term>
        <term>
            <termIdentifier>Fifths_Table_Highest</termIdentifier>
            <caption>
                <langstring language="en-US">Fifths_Table_Highest</langstring>
            </caption>
            <description>
                <langstring language="en-US">Count of examinees in the highest fifth of the test score distribution who selected the specified option.</langstring>
            </description>
            <metadata>
                <lom xmlns="http://ltsc.ieee.org/xsd/LOM">
                    <general>
                        <keyword>
                            <string>Item Statistics, Fifths_Table_Highest, IMS Global QTIv2.2</string>
                        </keyword>
                    </general>
                    <relation>
                        <resource>
                            <description>
                                <string>IMS Global</string>
                            </description>
                        </resource>
                    </relation>
                    <lifeCycle>
                        <contribute>
                            <role>
                                <value>publisher</value>
                            </role>
                            <entity>IMS Global Learning Consortium Inc.</entity>
                            <date>
                                <dateTime>2015-03-01</dateTime>
                            </date>
                        </contribute>
                        <status>
                            <value>Final</value>
                        </status>
                    </lifeCycle>
                </lom>
            </metadata>
        </term>
        <term>
            <termIdentifier>Fifths_Table_Lowest</termIdentifier>
            <caption>
                <langstring language="en-US">Fifths_Table_Lowest</langstring>
            </caption>
            <description>
                <langstring language="en-US">Count of examinees in the lowest fifth of the test score distribution who selected the specified option.</langstring>
            </description>
            <metadata>
                <lom xmlns="http://ltsc.ieee.org/xsd/LOM">
                    <general>
                        <keyword>
                            <string>Item Statistics, Fifths_Table_Lowest, IMS Global QTIv2.1</string>
                        </keyword>
                    </general>
                    <relation>
                        <resource>
                            <description>
                                <string>IMS Global</string>
                            </description>
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                        <contribute>
                            <role>
                                <value>publisher</value>
                            </role>
                            <entity>IMS Global Learning Consortium Inc.</entity>
                            <date>
                                <dateTime>2015-03-01</dateTime>
                            </date>
                        </contribute>
                        <status>
                            <value>Final</value>
                        </status>
                    </lifeCycle>
                </lom>
            </metadata>
        </term>
        <term>
            <termIdentifier>Fifths_Table_Middle</termIdentifier>
            <caption>
                <langstring language="en-US">Fifths_Table_Middle</langstring>
            </caption>
            <description>
                <langstring language="en-US">Count of examinees in the middle fifth of the test score distribution who selected the specified option.</langstring>
            </description>
            <metadata>
                <lom xmlns="http://ltsc.ieee.org/xsd/LOM">
                    <general>
                        <keyword>
                            <string>Item Statistics, Fifths_Table_Middle, IMS Global QTIv2.2</string>
                        </keyword>
                    </general>
                    <relation>
                        <resource>
                            <description>
                                <string>IMS Global</string>
                            </description>
                        </resource>
                    </relation>
                    <lifeCycle>
                        <contribute>
                            <role>
                                <value>publisher</value>
                            </role>
                            <entity>IMS Global Learning Consortium Inc.</entity>
                            <date>
                                <dateTime>2015-03-01</dateTime>
                            </date>
                        </contribute>
                        <status>
                            <value>Final</value>
                        </status>
                    </lifeCycle>
                </lom>
            </metadata>
        </term>
        <term>
            <termIdentifier>Fifths_Table_Second_Highest</termIdentifier>
            <caption>
                <langstring language="en-US">Fifths_Table_Second_Highest</langstring>
            </caption>
            <description>
                <langstring language="en-US">Count of examinees in the second highest fifth of the test score distribution who selected the specified option.</langstring>
            </description>
            <metadata>
                <lom xmlns="http://ltsc.ieee.org/xsd/LOM">
                    <general>
                        <keyword>
                            <string>Item Statistics, Fifths_Table_Second_Highest, IMS Global QTIv2.2</string>
                        </keyword>
                    </general>
                    <relation>
                        <resource>
                            <description>
                                <string>IMS Global</string>
                            </description>
                        </resource>
                    </relation>
                    <lifeCycle>
                        <contribute>
                            <role>
                                <value>publisher</value>
                            </role>
                            <entity>IMS Global Learning Consortium Inc.</entity>
                            <date>
                                <dateTime>2015-03-01</dateTime>
                            </date>
                        </contribute>
                        <status>
                            <value>Final</value>
                        </status>
                    </lifeCycle>
                </lom>
            </metadata>
        </term>
        <term>
            <termIdentifier>Fifths_Table_Second_Lowest</termIdentifier>
            <caption>
                <langstring language="en-US">Fifths_Table_Second_Lowest</langstring>
            </caption>
            <description>
                <langstring language="en-US">Count of examinees in the second lowest fifth of the test score distribution who selected the specified option.</langstring>
            </description>
            <metadata>
                <lom xmlns="http://ltsc.ieee.org/xsd/LOM">
                    <general>
                        <keyword>
                            <string>Item Statistics, Fifths_Table_Second_Lowest, IMS Global QTIv2.2</string>
                        </keyword>
                    </general>
                    <relation>
                        <resource>
                            <description>
                                <string>IMS Global</string>
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                            <role>
                                <value>publisher</value>
                            </role>
                            <entity>IMS Global Learning Consortium Inc.</entity>
                            <date>
                                <dateTime>2015-03-01</dateTime>
                            </date>
                        </contribute>
                        <status>
                            <value>Final</value>
                        </status>
                    </lifeCycle>
                </lom>
            </metadata>
        </term>
        <term>
            <termIdentifier>P-value</termIdentifier>
            <caption>
                <langstring language="en-US">P-value</langstring>
            </caption>
            <description>
                <langstring language="en-US">A group-dependent measure of item difficulty. It is equal to the percent answering the item correctly.</langstring>
            </description>
            <metadata>
                <lom xmlns="http://ltsc.ieee.org/xsd/LOM">
                    <general>
                        <keyword>
                            <string>Item Statistics, P-value, IMS Global QTIv2.2</string>
                        </keyword>
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                    <relation>
                        <resource>
                            <description>
                                <string>IMS Global</string>
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                            <role>
                                <value>publisher</value>
                            </role>
                            <entity>IMS Global Learning Consortium Inc.</entity>
                            <date>
                                <dateTime>2015-03-01</dateTime>
                            </date>
                        </contribute>
                        <status>
                            <value>Final</value>
                        </status>
                    </lifeCycle>
                </lom>
            </metadata>
        </term>
        <term>
            <termIdentifier>PHI</termIdentifier>
            <caption>
                <langstring language="en-US">Phi coefficient</langstring>
            </caption>
            <description>
                <langstring language="en-US">A group-dependent measure of item discrimination, Phi is the correlation of two dichotomous variables. In item analysis, it is generally the correlation between getting an item right or wrong and some dichotomous variable e.g. pass, fail.</langstring>
            </description>
            <metadata>
                <lom xmlns="http://ltsc.ieee.org/xsd/LOM">
                    <general>
                        <keyword>
                            <string>Item Statistics, PHI, IMS Global QTIv2.2</string>
                        </keyword>
                    </general>
                    <relation>
                        <resource>
                            <description>
                                <string>IMS Global</string>
                            </description>
                        </resource>
                    </relation>
                    <lifeCycle>
                        <contribute>
                            <role>
                                <value>publisher</value>
                            </role>
                            <entity>IMS Global Learning Consortium Inc.</entity>
                            <date>
                                <dateTime>2015-03-01</dateTime>
                            </date>
                        </contribute>
                        <status>
                            <value>Final</value>
                        </status>
                    </lifeCycle>
                </lom>
            </metadata>
        </term>
        <term>
            <termIdentifier>PTbis</termIdentifier>
            <caption>
                <langstring language="en-US">r-pointbiserial</langstring>
            </caption>
            <description>
                <langstring language="en-US">A group-dependent measure of item discrimination, r-pointbiserial is the point biserial correlation between the score on a dichotomous item and a criterion which is a variable that can take many possible values, such as total score on the test.</langstring>
            </description>
            <metadata>
                <lom xmlns="http://ltsc.ieee.org/xsd/LOM">
                    <general>
                        <keyword>
                            <string>Item Statistics, PTbis, IMS Global QTIv2.1</string>
                        </keyword>
                    </general>
                    <relation>
                        <resource>
                            <description>
                                <string>IMS Global</string>
                            </description>
                        </resource>
                    </relation>
                    <lifeCycle>
                        <contribute>
                            <role>
                                <value>publisher</value>
                            </role>
                            <entity>IMS Global Learning Consortium Inc.</entity>
                            <date>
                                <dateTime>2015-03-01</dateTime>
                            </date>
                        </contribute>
                        <status>
                            <value>Final</value>
                        </status>
                    </lifeCycle>
                </lom>
            </metadata>
        </term>
        <term>
            <termIdentifier>Polyserial</termIdentifier>
            <caption>
                <langstring language="en-US">Polyserial</langstring>
            </caption>
            <description>
                <langstring language="en-US">The polyserial correlation is the generalization of the biserial correlation for use with either dichotomous or polytomous items. For example, it may be the generalized form of the correlation with a criterion. It is the correlation of the item score with some continuous variable, usually the total score on the test.</langstring>
            </description>
            <metadata>
                <lom xmlns="http://ltsc.ieee.org/xsd/LOM">
                    <general>
                        <keyword>
                            <string>Item Statistics, Polyserial, IMS Global QTIv2.2</string>
                        </keyword>
                    </general>
                    <relation>
                        <resource>
                            <description>
                                <string>IMS Global</string>
                            </description>
                        </resource>
                    </relation>
                    <lifeCycle>
                        <contribute>
                            <role>
                                <value>publisher</value>
                            </role>
                            <entity>IMS Global Learning Consortium Inc.</entity>
                            <date>
                                <dateTime>2015-03-01</dateTime>
                            </date>
                        </contribute>
                        <status>
                            <value>Final</value>
                        </status>
                    </lifeCycle>
                </lom>
            </metadata>
        </term>
        <term>
            <termIdentifier>Score_Conversion</termIdentifier>
            <caption>
                <langstring language="en-US">Score Conversion Table</langstring>
            </caption>
            <description>
                <langstring language="en-US">Raw scores and their corresponding converted values e.g. the values to be used in score reports.</langstring>
            </description>
            <metadata>
                <lom xmlns="http://ltsc.ieee.org/xsd/LOM">
                    <general>
                        <keyword>
                            <string>Item Statistics, Score_Conversion, IMS Global QTIv2.2</string>
                        </keyword>
                    </general>
                    <relation>
                        <resource>
                            <description>
                                <string>IMS Global</string>
                            </description>
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                        <contribute>
                            <role>
                                <value>publisher</value>
                            </role>
                            <entity>IMS Global Learning Consortium Inc.</entity>
                            <date>
                                <dateTime>2015-03-01</dateTime>
                            </date>
                        </contribute>
                        <status>
                            <value>Final</value>
                        </status>
                    </lifeCycle>
                </lom>
            </metadata>
        </term>
        <term>
            <termIdentifier>rbis</termIdentifier>
            <caption>
                <langstring language="en-US">r-biserial</langstring>
            </caption>
            <description>
                <langstring language="en-US">A group-dependent measure of item discrimination, r-biserial is an estimate of the biserial correlation between a latent continuous variable hypothesised to underlie performance on a dichotomous item (i.e. item score) and a criterion which is a variable that can take many possible vales, such as total score on the test.</langstring>
            </description>
            <metadata>
                <lom xmlns="http://ltsc.ieee.org/xsd/LOM">
                    <general>
                        <keyword>
                            <string>Item Statistics, rbis, IMS Global QTIv2.2</string>
                        </keyword>
                    </general>
                    <relation>
                        <resource>
                            <description>
                                <string>IMS Global</string>
                            </description>
                        </resource>
                    </relation>
                    <lifeCycle>
                        <contribute>
                            <role>
                                <value>publisher</value>
                            </role>
                            <entity>IMS Global Learning Consortium Inc.</entity>
                            <date>
                                <dateTime>2015-03-01</dateTime>
                            </date>
                        </contribute>
                        <status>
                            <value>Final</value>
                        </status>
                    </lifeCycle>
                </lom>
            </metadata>
        </term>
        <metadata>
            <lom xmlns="http://ltsc.ieee.org/xsd/LOM">
                <general>
                    <title>
                        <string>IMS Global QTI Glossary of Terms for Usage Data Item Statistics</string>
                    </title>
                    <keyword>
                        <string>QTIv2.2, Usage Data, Item Statistics Glossary</string>
                    </keyword>
                    <language>en-US</language>
                    <description>
                        <string>Description: The set of terms that would be used to collect the item statistics. This is the value that will be entered in the 'name' element.</string>
                        <string>History: The first formal release of this QTI Glossary as part of QTIv2.2.</string>
                    </description>
                </general>
                <lifeCycle>
                    <contribute>
                        <role>
                            <value>author</value>
                        </role>
                        <entity>Colin Smythe (IMS Global, UK) and Mark McKell (IMS Global, USA)</entity>
                    </contribute>
                    <version>
                        <string>1.0</string>
                    </version>
                    <status>
                        <value>Final Release</value>
                    </status>
                    <contribute>
                        <role>
                            <value>publisher</value>
                        </role>
                        <entity>IMS Global Learning Consortium Inc.</entity>
                        <date>
                            <dateTime>2015-06-01</dateTime>
                        </date>
                    </contribute>
                </lifeCycle>
                <rights>
                    <copyrightAndOtherRestrictions>
                        <value>yes</value>
                    </copyrightAndOtherRestrictions>
                    <description>
                        <string>2015 (c) IMS Global Learning Consortium Inc.</string>
                    </description>
                </rights>
                <technical>
                    <format>XML</format>
                </technical>
            </lom>
        </metadata>
    </vdex>

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# About this Document

Title: | IMS Question and Test Interoperability (QTI): Usage Data Information Model and XSD Binding v2.2
Editors: | Colin Smythe, IMS Global (UK) Mark McKell, IMS Global (USA) Wilbert Kraan, JISC (UK)
Co-chairs: | Wilbert Kraan, JISC (UK) Tom Hoffmann, ETS (USA)
Version: | 1.0.1
Version Date: | 1st August, 2016
Status: | IMS Final Release
Summary: | This is the definition of the data model and the corresponding XSD binding to be used to support the exchange of QTI Usage Data. This data model defines the object model for the exchange of a QTI-specific Usage Data Statistics (it assumes the definition of Items based upon IMS QTI Assessment, Section and Item v2.2 specification but this is not essential). The data model and XSD binding is described using the IMS profile of UML to support the IMS model driven specification engineering method.
Revision Information: | This document supercedes IMS QTI Usage Data Information Model and XSD Binding v2.1. Version 1.0.1 document is updated for consistency with the QTI ASI 2.2.1 XSD release.
Purpose: | This document is made available for adoption by the public community at large.
Document Location: | IMS Public Website (Standards Download): www.imsglobal.org/question

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## List of Contributors

The following individuals contributed to the development of this document:

Mike Aumock | Pacific Metrics (USA)
Jerome Bogaerts | O.A.T. (Luxemburgh)
Marty Christensen | ACT (USA)
Jason Craft | Pearson (USA)
Gary Driscoll | ETS (USA)
Gaye Fedorachak | ACT (USA)
Greg Gaspard | Pearson (USA)
Mark Hakkinen | ETS (USA)
Regina Hoag | ETS (USA)
Tom Hoffmann | ETS (USA)
Rob Howard | NWEA (USA)
Wilbert Kraan | JISC (UK)
Makoto Marata | JEPA (Japan)
Justin Marks | NWEA (USA)
Phil McClelland | Desire2Learn (Canada)
Mark McKell | IMS Global (USA)

Sue Milne | JISC/CETIS (UK)
Becka Nethers | NWEA (USA)
Padraig O'hiceadha | HMH (UK)
Jason Pelletier | Measured Progress (USA)
Craig Perry | ACT (USA)
Kevin Ptak | Data Recognition Corps (USA)
Michelle Richards | Pearson (USA)
Madeleine Rothberg | WGBH NCAM (USA)
Sharon Secretan | NWEA (USA)
Farhat Siddiqui | ETS (USA)
Colin Smythe | IMS Global (UK)
Joseph St. George | Measured Progress (USA)
Jeremiah Tanner | DRC (USA)
Wyatt VanderStucken | ETS (USA)
Yvonne Winklemann | BPS (Germany)

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## Revision History

Version No. | Release Date | Comments
--- | --- | ---
Final 1.0 | 1st September, 2015 | The first formal release of QTI Usage Data v2.2 Specification. This is a combined Information Model an XSD Binding document.
Final 1.0.1 | 1st August, 2016 | Updated to provide consistency for references to the QTI ASI 2.2.1 XSD revision release.

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IMS Global Learning Consortium, Inc. ("IMS Global") is publishing the information contained in this document ("Specification") for purposes of scientific, experimental, and scholarly collaboration only.

IMS Global makes no warranty or representation regarding the accuracy or completeness of the Specification.

This material is provided on an "As Is" and "As Available" basis.

The Specification is at all times subject to change and revision without notice.

It is your sole responsibility to evaluate the usefulness, accuracy, and completeness of the Specification as it relates to you.

IMS Global would appreciate receiving your comments and suggestions.

Please contact IMS Global through our website at http://www.imsglobal.org.

Please refer to Document Name: IMS Question and Test Interoperability (QTI): Usage Data Information Model and XSD Binding v2.2

Date: 1st August, 2016

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