IMS Question and Test Interoperability Assessment Test, Section, and Item Information Model

Attribute : identifier [1]: string
The principle identifier of the item. This identifier must have a corresponding entry in the item's meta-data. See Meta-data and Usage Data for more information.

Attribute : title [1]: string
The title of an assessmentItem is intended to enable the item to be selected in situations where the full text of the itemBody is not available, for example when a candidate is browsing a set of items to determine the order in which to attempt them. Therefore, delivery engines may reveal the title to candidates at any time but are not required to do so.

Attribute : label [0..1]: string256

Attribute : lang [0..1]: language

Attribute : adaptive [1]: boolean = false
Items are classified into Adaptive Items and Non-adaptive Items.

Attribute : timeDependent [1]: boolean

Attribute : toolName [0..1]: string256
The tool name attribute allows the tool creating the item to identify itself. Other processing systems may use this information to interpret the content of application specific data, such as labels on the elements of the item's itemBody.

Attribute : toolVersion [0..1]: string256
The tool version attribute allows the tool creating the item to identify its version. This value must only be interpreted in the context of the toolName

Contains : responseDeclaration [*]

Contains : outcomeDeclaration [*]

Contains : templateDeclaration [*]

Contains : templateProcessing [0..1]

Contains : stylesheet [0..*]

Contains : itemBody [0..1]

Contains : responseProcessing [0..1]

Contains : modalFeedback [*]

When items are referenced as part of a test, the test may impose constraints on how many attempts and which states are allowed. These constraints can be specified for individual items, for whole sections, or for an entire testPart. By default, a setting at testPart level affects all items in that part unless the setting is overridden at the assessmentSection level or ultimately at the individual assessmentItemRef. The defaults given below are used only in the absence of any applicable constraint.

Attribute : maxAttempts [0..1]: integer
For non-adaptive items, maxAttempts controls the maximum number of attempts allowed in the given test context. Normally this is 1 as the scoring rules for non-adaptive items are the same for each attempt. A value of 0 indicates no limit. If it is unspecified it is treated as 1 for non-adaptive items. For adaptive items, the value of maxAttempts is ignored as the number of attempts is limited by the value of the completionStatus built-in outcome variable.

A value of maxAttempts greater than 1, by definition, indicates that any applicable feedback must be shown. This applies to both Modal Feedback and Integrated Feedback where applicable. However, once the maximum number of allowed attempts have been used (or for adaptive items, completionStatus has been set to completed) whether or not feedback is shown is controlled by the showFeedback constraint.

Attribute : showFeedback [0..1]: boolean
This constraint affects the visibility of feedback after the end of the last attempt. If it is false then feedback is not shown. This includes both Modal Feedback and Integrated Feedback even if the candidate has access to the review state. The default is false.

Attribute : allowReview [0..1]: boolean
This constraint also applies only after the end of the last attempt. If set to true the item session is allowed to enter the review state during which the candidate can review the itemBody along with the responses they gave, but cannot update or resubmit them. If set to false the candidate can not review the itemBody or their responses once they have submitted their last attempt. The default is true.

If the review state is allowed, but feedback is not, delivery systems must take extra care not to show integrated feedback that resulted from the last attempt as part of the review process. Feedback can however take the form of hiding material that was previously visible, as well as the more usual form of showing material that was previously hidden.

To resolve this ambiguity, for non-adaptive items the absence of feedback is defined to be the version of the itemBody displayed to the candidate at the start of each attempt. In other words, with the visibility of any integrated feedback determined by the default values of the outcome variables and not the values of the outcome variables updated by the invocation of response processing.

For Adaptive Items the situation is complicated by the iterative nature of response processing which makes it hard to identify the appropriate state in which to place the item for review. To avoid requiring delivery engines to cache the values of the outcome variables the setting of showFeedback should be ignored for adaptive items when allowReview is true. When in the review state, the final values of the outcome variables should be used to determine the visibility of integrated feedback.

Attribute : showSolution [0..1]: boolean
This constraint controls whether or not the system may provide the candidate with a way of entering the solution state. The default is false.

Attribute : allowComment [0..1]: boolean
Some delivery systems support the capture of candidate comments. The comment is not part of the assessed responses but provides feedback from the candidate to the other actors in the assessment process. This constraint controls whether or not the candidate is allowed to provide a comment on the item during the session.

Attribute : allowSkipping [0..1]: boolean = true
An item is defined to be skipped if the candidate has not provided any response. In other words, all response variables are submitted with their default value or are NULL. This definition is consistent with the numberResponded operator available in outcomeProcessing. If false, candidates are not allowed to skip the item, or in other words, they are not allowed to submit the item until they have provided a non-default value for at least one of the response variables. By definition, an item with no response variables cannot be skipped. The value of this attribute is only applicable when the item is in a testPart with individual submission mode. Note that if allowSkipping is true delivery engines must ensure that the candidate can choose to submit no response, for example, through the provision of a "skip" button.

Attribute : validateResponses [0..1]: boolean
This attribute controls the behavior of delivery engines when the candidate submits an invalid response. An invalid response is defined to be a response which does not satisfy the constraints imposed by the interaction with which it is associated. See interaction for more information. When validateResponses is turned on (true) then the candidates are not allowed to submit the item until they have provided valid responses for all interactions. When turned off (false) invalid responses may be accepted by the system. The value of this attribute is only applicable when the item is in a testPart with individual submission mode. (See Navigation and Submission.)

Figure 5.1 Variable Declarations.

Item variables are declared by variable declarations. All variables must be declared except for the built-in session variables referred to below which are declared implicitly and must not be declared. The purpose of the declaration is to associate an identifier with the variable and to identify the runtime type of the variable's value.

An item variable may have no value at all, in which case it is said to have the special value NULL. For example, if the candidate has not yet had an opportunity to respond to an interaction then any associated response variable will have a NULL value. Empty containers and empty strings are always treated as NULL values.

Attribute : identifier [1]: identifier
The identifiers of the built-in session variables are reserved. They are completionStatus, numAttempts and duration. All item variables declared in an item share the same namespace. Different items have different namespaces.

Attribute : cardinality [1]: cardinality
Each variable is either single valued or multi-valued. Multi-valued variables are referred to as containers and come in ordered, unordered and record types. See cardinality for more information.

Attribute : baseType [0..1]: baseType
The value space from which the variable's value can be drawn (or in the case of containers, from which the individual values are drawn) is identified with a baseType. The baseType selects one of a small set of predefined types that are considered to have atomic values within the runtime data model. Variables with record cardinality have no base-type.

Contains : defaultValue [0..1]
An optional default value for the variable. The point at which a variable is set to its default value varies depending on the type of item variable.

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.

Attribute : fieldIdentifier [0..1]: identifier
This attribute is only used for specifying the field identifier for a value that forms part of a record.

Attribute : baseType [0..1]: baseType
This attribute is only used for specifying the base-type of a value that forms part of a record.

Attribute : interpretation [0..1]: string
A human readable interpretation of the default value.

Contains : value [1..*]

single

multiple

ordered

record

An expression or itemVariable can either be single-valued or multi-valued. A multi-valued expression (or variable) is called a container. A container contains a list of values, this list may be empty in which case it is treated as NULL. All the values in a multiple or ordered container are drawn from the same value set, however, containers may contain multiple occurrences of the same value. In other words, [A,B,B,C] is an acceptable value for a container. A container with cardinality multiple and value [A,B,C] is equivalent to a similar one with value [C,B,A] whereas these two values would be considered distinct for containers with cardinality ordered. When used as the value of a response variable this distinction is typified by the difference between selecting choices in a multi-response multi-choice task and ranking choices in an order objects task. In the language of [ISO11404] a container with multiple cardinality is a "bag-type", a container with ordered cardinality is a "sequence-type" and a container with record cardinality is a "record-type".

The record container type is a special container that contains a set of independent values each identified by its own identifier and having its own base-type. This specification does not make use of the record type directly however it is provided to enable customInteractions to manipulate more complex responses and customOperators to return more complex values.

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.

identifier
The set of identifier values is the same as the set of values defined by the identifier class.

boolean
The set of boolean values is the same as the set of values defined by the boolean class.

integer
The set of integer values is the same as the set of values defined by the integer class.

float
The set of float values is the same as the set of values defined by the float class.

string
The set of string values is the same as the set of values defined by the string class.

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.

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.

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 [ISO8601]. Durations are measured in seconds and may have a fractional part.

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 [RFC2045].

uri
A URI value is a Uniform Resource Identifier as defined by [URI].

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.

Attribute : lowerBound [0..1]: float
The lower bound for the result of mapping a container. If unspecified there is no lower-bound.

Attribute : upperBound [0..1]: float
The upper bound for the result of mapping a container. If unspecified there is no upper-bound.

Attribute : defaultValue [1]: float = 0
The default value from the target set to be used when no explicit mapping for a source value is given.

Contains : mapEntry [1..*]
The map is defined by a set of mapEntries, each of which maps a single value from the source set onto a single float.

Attribute : mapKey [1]: valueType
The source value

Attribute : mappedValue [1]: float
The mapped value

Response variables are declared by response declarations and bound to interactions in the itemBody.

At runtime, response variables are instantiated as part of an item session. Their values are always initialized to NULL (no value) regardless of whether or not a default value is given in the declaration. A response variable with a NULL value indicates that the candidate has not offered a response, either because they have not attempted the item at all or because they have attempted it and chosen not to provide a response.

If a default value has been provided for a response variable then the variable is set to this value at the start of the first attempt. If the candidate never attempts the item, in other words, the item session passes straight from the initial state to the closed state without going through the interacting state, then the response variable remains NULL and the default value is never used.

Implementors of Delivery Engines should take care when implementing user interfaces for items with default response variable values. If the associated interaction is left in the default state (i.e., representing the default value) then it is important that the system is confident that the candidate intended to submit this value and has not simply failed to notice that a default has been provided. This is especially true if the candidate's attempt ended due to some external event, such as running out of time. The techniques required to distinguish between these cases are an issue for user interface design and are therefore out of scope for this specification.

Contains : correctResponse [0..1]
A response declaration may assign an optional correctResponse. This value may indicate the only possible value of the response variable to be considered correct or merely just a correct value. For responses that are being measured against a more complex scale than correct/incorrect this value should be set to the (or an) optimal value. Finally, for responses for which no such optimal value is defined the correctResponse must be omitted. If a delivery system supports the display of a solution then it should display the correct values of responses (where defined) to the candidate. When correct values are displayed they must be clearly distinguished from the candidate's own responses (which may be hidden completely if necessary).

Contains : mapping [0..1]
The mapping provides a mapping from the set of base values to a set of numeric values for the purposes of response processing. See mapResponse for information on how to use the mapping.

Contains : areaMapping [0..1]
The areaMapping, which may only be present in declarations of variables with baseType point, provides an alternative form of mapping which tests against areas of the coordinate space instead of mapping single values (i.e., single points).

Attribute : interpretation [0..1]: string
A human readable interpretation of the correct value.

Contains : value [1..*]

A special class used to create a mapping from a source set of point values to a target set of float values. When mapping containers, the result is the sum of the mapped values from the target set. See mapResponsePoint for details. The attributes have the same meaning as the similarly named attributes on mapping.

Attribute : lowerBound [0..1]: float

Attribute : upperBound [0..1]: float

Attribute : defaultValue [1]: float = 0

Contains : areaMapEntry [1..*] {ordered}
The map is defined by a set of areaMapEntries, each of which maps an area of the coordinate space onto a single float. When mapping points each area is tested in turn, with those listed first taking priority in the case where areas overlap and a point falls in the intersection.

Attribute : shape [1]: shape
The shape of the area.

Attribute : coords [1]: coords
The size and position of the area, interpreted in conjunction with the shape.

Attribute : mappedValue [1]: float
The mapped value

Outcome variables are declared by outcome declarations. Their value is set either from a default given in the declaration itself or by a responseRule during responseProcessing.

Items that declare a numeric outcome variable representing the candidate's overall performance on the item should use the outcome name 'SCORE' for the variable.

At runtime, outcome variables are instantiated as part of an item session. Their values may be initialized with a default value and/or set during responseProcessing. If no default value is given in the declaration then the outcome variable is initialized to NULL unless the outcome is of a numeric type (integer or float) in which case it is initialized to 0.

For Non-adaptive Items, the values of the outcome variables are reset to their default values prior to each invocation of responseProcessing. For Adaptive Items the outcome variables retain the values that were assigned to them during the previous invocation of response processing. For more information, see Response Processing.

Attribute : view [*]: view
The intended audience for an outcome variable can be set with the view attribute. If no view is specified the outcome is treated as relevant to all views. Complex items, such as adaptive items or complex templates, may declare outcomes that are of no interest to the candidate at all, but are merely used to hold intermediate values or other information useful during the item or test session. Such variables should be declared with a view of author (for item outcomes) or testConstructor (for test outcomes). Systems may exclude outcomes from result reports on the basis of their declared view if appropriate.

Attribute : interpretation [0..1]: string
A human interpretation of the variable's value.

Attribute : longInterpretation [0..1]: uri
An optional link to an extended interpretation of the outcome variable's value.

Declared outcomes with numeric types should indicate their range of possible values using normalMaximum and normalMinimum, especially if this range differs from [0,1].

Attribute : normalMaximum [0..1]: float
The normalMaximum attribute optionally defines the maximum magnitude of numeric outcome variables, it must be a positive value. If given, the outcome's value can be divided by normalMaximum and then truncated (if necessary) to obtain a normalized score in the range [-1.0,1.0]. normalMaximum has no affect on responseProcessing or the values that the outcome variable itself can take.

Attribute : normalMinimum [0..1]: float
The normalMinimum attribute optionally defines the minimum value of numeric outcome variables, it may be negative.

Attribute : masteryValue [0..1]: float
The masteryValue attribute optionally defines a value for numeric outcome variables above which the aspect being measured is considered to have been mastered by the candidate.

Contains : lookupTable [0..1]

An abstract class associated with an outcomeDeclaration used to create a lookup table from a numeric source value to a single outcome value in the declared value set. A lookup table works in the reverse sense to the similar mapping as it defines how a source numeric value is transformed into the outcome value, whereas a (response) mapping defines how the response value is mapped onto a target numeric value.

The transformation takes place using the lookupOutcomeValue rule within responseProcessing or outcomeProcessing.

Attribute : defaultValue [0..1]: valueType
The default outcome value to be used when no matching table entry is found. If omitted, the NULL value is used.

A matchTable transforms a source integer by finding the first matchTableEntry with an exact match to the source.

Contains : matchTableEntry [1..*]

Attribute : sourceValue [1]: integer
The source integer that must be matched exactly.

Attribute : targetValue [1]: valueType
The target value that is used to set the outcome when a match is found.

An interpolationTable transforms a source float (or integer) by finding the first interpolationTableEntry with a sourceValue that is less than or equal to (subject to includeBoundary) the source value.

For example, an interpolation table can be used to map a raw numeric score onto an identifier representing a grade. It may also be used to implement numeric transformations such as those from a simple raw score to a value on a calibrated scale.

Contains : interpolationTableEntry [1..*]

Attribute : sourceValue [1]: float
The lower bound for the source value to match this entry.

Attribute : includeBoundary [0..1]: boolean = true
Determines if an exact match of sourceValue matches this entry. If true, the default, then an exact match of the value is considered a match of this entry.

Attribute : targetValue [1]: valueType
The target value that is used to set the outcome when a match is found.

Contains : block [*]

The item body contains the text, graphics, media objects, and interactions that describe the item's content and information about how it is structured. The body is presented by combining it with stylesheet information, either explicitly or implicitly using the default style rules of the delivery or authoring system.

The body must be presented to the candidate when the associated item session is in the interacting state. In this state, the candidate must be able to interact with each of the visible interactions and therefore set or update the values of the associated response variables. The body may be presented to the candidate when the item session is in the closed or review state. In these states, although the candidate's responses should be visible, the interactions must be disabled so as to prevent the candidate from setting or updating the values of the associated response variables. Finally, the body may be presented to the candidate in the solution state, in which case the correct values of the response variables must be visible and the associated interactions disabled.

The root class of all content objects in the item content model is the bodyElement. It defines a number of attributes that are common to all elements of the content model.

Attribute : id [0..1]: identifier
The id of a body element must be unique within the item.

Attribute : class [*]: styleclass
Classes can be assigned to individual body elements. Multiple class names can be given. These class names identify the element as being a member of the listed classes. Membership of a class can be used by authoring systems to distinguish between content objects that are not differentiated by this specification. Typically, this information is used to apply different formatting based on definitions in an associated stylesheet.

Attribute : lang [0..1]: language
The main language of the element. This attribute is optional and will usually be inherited from the enclosing element.

Attribute : label [0..1]: string256
The label attribute provides authoring systems with a mechanism for labeling elements of the content model with application specific data. If an item uses labels then values for the associated toolName and toolVersion attributes must also be provided.

Elements that can appear within an object.

Elements that behave as spans of text, such as the contents of paragraphs.

Elements that provide structure to the text, such as paragraphs, tables etc. Most elements are either inline or block elements.

Elements that can appear inside list items, table cells, etc. which includes block-type and inline-type elements.

Attribute : base [0..1]: uri
An optional URI used to change the base for resolving relative URI for the scope of this object. Particular care needs to be taken when resolving relative URI included as part of an Item Fragment. See Item and Test Fragments for more information.

A sub-class of inline that excludes interactions.

A sub-class of block that excludes interactions.

A sub-class of flow that excludes interactions.

Contains : inline [*]

Contains : block [*]

Contains : inline [*]

A text run is simply a run of characters. Unlike all other elements in the content model it is not a sub-class of bodyElement. To assign attributes to a run of text you must use the span element instead.

Note that the title attribute defined by XHTML is not supported.

Note that the title attribute defined by XHTML is not supported.

Attribute : cite [0..1]: uri

Contains : flow [*]

Although pre inherits from atomicBlock it must not contain, either directly or indirectly, any of the following objects: img, object, big, small, sub, sup.

Attribute : cite [0..1]: uri

Contains : dlElement [*]

Contains : inline [*]

Contains : flow [*]

Contains : li [*]

Contains : li [*]

Contains : flow [*]

Contains : objectFlow [*]

Attribute : data [1]: string
The data attribute provides a URI for locating the data associated with the object.

Attribute : type [1]: mimeType

Attribute : width [0..1]: length

Attribute : height [0..1]: length

Attribute : name [1]: string
The name of the parameter, as interpreted by the object.

Attribute : value [1]: string
The value to pass to the object for the named parameter. This value is subject to template variable expansion. If the value is the name of a template variable that was declared with the paramVariable set to true then the template variable's value is passed to the object as the value for the given parameter.

When expanding a template variable as a parameter value, types other than identifiers, strings and uris must be converted to strings. Numeric types are converted to strings using the "%i" or "%G" formats as appropriate (see printedVariable for a discussion of numeric formatting). Values of base-type boolean are expanded to one of the strings "true" or "false". Values of base-type point are expanded to two space-separated integers in the order horizontal coordinate, vertical coordinate, using "%i" format. Values of base-type pair and directedPair are converted to a string consisting of the two identifiers, space separated. Values of base-type duration are converted using "%G" format. Values of base-type file cannot be used in parameter expansion.

If the valuetype is REF the template variable must be of base-type uri.

Attribute : valuetype [1]: paramType = DATA
This specification supports the use of DATA and REF but not OBJECT.

Attribute : type [0..1]: mimeType
Used to provide a type for values valuetype REF.

DATA

REF

Contains : inline [*]

Attribute : span [0..1]: integer = 1

Attribute : span [0..1]: integer = 1

Contains : col [*]

Attribute : summary [0..1]: string

Contains : caption [0..1]

Contains : col [*]
If a table directly contains a col then it must not contain any colgroup elements.

Contains : colgroup [*]
If a table contains a colgroup it must not directly contain any col elements.

Contains : thead [0..1]

Contains : tfoot [0..1]

Contains : tbody [1..*]

In XHTML, table cells are represented by either th or td and these share the following attributes and content model:

Attribute : headers [*]: identifier

Attribute : scope [0..1]: tableCellScope

Attribute : abbr [0..1]: string

Attribute : axis [0..1]: string

Attribute : rowspan [0..1]: integer

Attribute : colspan [0..1]: integer

Contains : flow [*]

row

col

rowgroup

colgroup

Contains : tr [1..*]

Contains : tr [1..*]

Contains : tr [1..*]

Contains : tableCell [1..*]

Attribute : src [1]: uri

Attribute : alt [1]: string256

Attribute : longdesc [0..1]: uri

Attribute : height [0..1]: length

Attribute : width [0..1]: length

Although a inherits from simpleInline it must not contain, either directly or indirectly, another a.

Attribute : href [1]: uri

Attribute : type [0..1]: mimeType

The math class is defined externally by the MathML specification. It can behave in the item's content model as an inline, block or flow element.

Attribute : outcomeIdentifier [1]: identifier
The identifier of an outcome variable that must have a base-type of identifier and be of either single or multiple cardinality. The visibility of the feedbackElement is controlled by assigning a value (or values) to this outcome variable during responseProcessing.

Attribute : showHide [1]: showHide = show
The showHide attribute determines how the visibility of the feedbackElement is controlled. If set to show then the feedback is hidden by default and shown only if the associated outcome variable matches, or contains, the value of the identifier attribute. If set to hide then the feedback is shown by default and hidden if the associated outcome variable matches, or contains, the value of the identifier attribute.

Attribute : identifier [1]: identifier
The identifier that determines the visibility of the feedback in conjunction with the showHide attribute.

A feedback element that forms part of a Non-adaptive Item must not contain an interaction object, either directly or indirectly.

When an interaction is contained in a hidden feedback element it must also be hidden. The candidate must not be able to set or update the value of the associated response variables.

show

hide

Attribute : view [1..*]: view
The views in which the rubric block's content are to be shown.

A rubric block identifies part of an assessmentItem's itemBody that represents instructions to one or more of the actors that view the item. Although rubric blocks are defined as simpleBlocks they must not contain interactions.

Attribute : identifier [1]: identifier
The outcome variable or template variable that must have been defined and have single cardinality. The values of response variables cannot be printed directly as their values are implicitly known to the candidate through the interactions they are bound to. If necessary, their values can be assigned to outcomes during responseProcessing and displayed to the candidate as part of a bodyElement visible only in the appropriate feedback states.

If the variable's value is NULL then the element is ignored.

Variables of baseType string are treated as simple runs of text.

Variables of baseType integer or float are converted to runs of text (strings) using the formatting rules described below. Float values should only be formatted in the e, E, f, g, G, r or R styles.

Variables of baseType duration are treated as floats, representing the duration in seconds.

Attribute : format [0..1]: string256
The format conversion specifier to use when converting numerical values to strings. See Number Formatting Rules for details.

Attribute : base [0..1]: integer = 10
The number base to use when converting integer variables to strings with the i conversion type code.

Variables of baseType file are rendered using a control that enables the user to open the file. The control should display the name associated with the file, if any.

Variables of baseType uri are rendered using a control that enables the user to open the identified resource, for example, by following a hypertext link in the case of a URL.

An abstract class used to enable variable value substitution in contexts where only plain text is allowed, such as the text of an inlineChoice.

Used to associate an external stylesheet with an assessmentItem.

Attribute : href [1]: uri
The identifier or location of the external stylesheet.

Attribute : type [1]: mimeType
The type of the external stylesheet.

Attribute : media [0..1]: string
An optional media descriptor that describes the media to which this stylesheet applies.

Attribute : title [0..1]: string
An optional title for the stylesheet.

Interactions allow the candidate to interact with the item. Through an interaction, the candidate selects or constructs a response. The candidate's responses are stored in the response variables. Each interaction is associated with (at least) one response variable.

Attribute : responseIdentifier [1]: identifier
The response variable associated with the interaction.

The state of the interaction is used to set the value of the associated response variable. The declaration of the associated response variable constrains the value of the response to be of a particular baseType and cardinality. Some interactions impose additional constraints on the set of allowable responses, for example, through constraining the minimum and/or maximum number of choices that can be selected in a choiceInteraction. In some interactive delivery engines it is possible to check these constraints while the candidate is interacting with the item. As the candidate navigates around a test they may see an indication of which items have valid responses and which require attention, or the candidate may be prevented from progressing through a test until a valid response has been selected/constructed. (See validateResponses for how to enforce this mode of operation during a test.) In some cases, delivery engines may even provide interactive controls that eliminate certain types of invalid response, for example, by restricting the number of choices that can be selected to prevent it exceeding the maximum specified for the interaction.

Given the possibility that a candidate may place an interaction into a state that does not satisfy these additional constraints, item authors must ensure that the response processing rules (if provided) deal appropriately with invalid values of the response variables.

An interaction that appears inline.

An interaction that behaves like a block in the content model. Most interactions are of this type.

Contains : prompt [0..1]
An optional prompt for the interaction.

Contains : inlineStatic [*]
A prompt must not contain any nested interactions.

Many of the interactions involve choosing one or more predefined choices. These choices all have the following attributes in common:

Attribute : identifier [1]: identifier
The identifier of the choice. This identifier must not be used by any other choice or item variable.

Attribute : fixed [0..1]: boolean = false
If fixed is true for a choice then the position of this choice within the interaction must not be changed by the delivery engine even if the immediately enclosing interaction supports the shuffling of choices. If no value is specified then the choice is free to be shuffled.

In Item Templates, the visibility of choices can be controlled by setting the value(s) of an associated template variable during template processing. For information about item templates see Item Templates.

Attribute : templateIdentifier [0..1]: identifier
The identifier of a template variable that must have a base-type of identifier and be either single of multiple cardinality. When the associated interaction is part of an Item Template the value of the identified template variable is used to control the visibility of the choice. When a choice is hidden it is not selectable and its content is not visible to the candidate unless otherwise stated.

Attribute : showHide [0..1]: showHide = show
The showHide attribute determines how the visibility of the choice is controlled. If set to show then the choice is hidden by default and shown only if the associated template variable matches, or contains, the identifier of the choice. If set to hide then the choice is shown by default and hidden if the associated template variable matches, or contains, the choice's identifier.

Other interactions involve associating pairs of predefined choices. These choices all have the following attribute in common:

Attribute : matchGroup [0..*]: identifier
A set of choices that this choice may be associated with, all others are excluded. If no matchGroup is given, or if it is empty, then all other choices may be associated with this one subject to their own matching constraints.

The choice interaction presents a set of choices to the candidate. The candidate's task is to select one or more of the choices, up to a maximum of maxChoices. There is no corresponding minimum number of choices. The interaction is always initialized with no choices selected.

The choiceInteraction must be bound to a response variable with a baseType of identifier and single or multiple cardinality.

Attribute : shuffle [1]: boolean = false
If the shuffle attribute is true then the delivery engine must randomize the order in which the choices are presented subject to the fixed attribute.

Attribute : maxChoices [1]: integer = 1
The maximum number of choices that the candidate is allowed to select. If maxChoices is 0 then there is no restriction. If maxChoices is greater than 1 (or 0) then the interaction must be bound to a response with multiple cardinality.

Attribute : minChoices [0..1]: integer = 0
The minimum number of choices that the candidate is required to select to form a valid response. If minChoices is 0 then the candidate is not required to select any choices. minChoices must be less than or equal to the limit imposed by maxChoices.

Contains : simpleChoice [1..*]
An ordered list of the choices that are displayed to the user. The order is the order of the choices presented to the user, unless shuffle is true.

In an order interaction the candidate's task is to reorder the choices, the order in which the choices are displayed initially is significant. By default the candidate's task is to order all of the choices but a subset of the choices can be requested using the maxChoices and minChoices attributes. When specified, the candidate must select a subset of the choices and impose an ordering on them.

If a default value is specified for the response variable associated with an order interaction then its value should be used to override the order of the choices specified here.

By its nature, an order interaction may be difficult to render in an unanswered state, especially in the default case where all choices are to be ordered. Implementors should be aware of the issues concerning the use of default values described in the section on Response Variables.

The orderInteraction must be bound to a response variable with a baseType of identifier and ordered cardinality only.

Contains : simpleChoice [1..*]
An ordered list of the choices that are displayed to the user. The order is the initial order of the choices presented to the user, unless shuffle is true.

Attribute : shuffle [1]: boolean = false
If the shuffle attribute is true then the delivery engine must randomize the order in which the choices are initially presented subject to the fixed attribute.

Attribute : minChoices [0..1]: integer
The minimum number of choices that the candidate must select and order to form a valid response to the interaction. If specified, minChoices must be 1 or greater but must not exceed the number of choices available. If unspecified, all of the choices must be ordered and maxChoices is ignored.

Attribute : maxChoices [0..1]: integer
The maximum number of choices that the candidate may select and order when responding to the interaction. Used in conjunction with minChoices, if specified, maxChoices must be greater than or equal to minChoices and must not exceed the number of choices available. If unspecified, all of the choices may be ordered.

Attribute : orientation [0..1]: orientation
The orientation attribute provides a hint to rendering systems that the ordering has an inherent vertical or horizontal interpretation.

Contains : flowStatic [*]

simpleChoice is a choice that contains flowStatic objects. A simpleChoice must not contain any nested interactions.

An associate interaction is a blockInteraction that presents candidates with a number of choices and allows them to create associations between them.

The associateInteraction must be bound to a response variable with base-type pair and either single or multiple cardinality.

Attribute : shuffle [1]: boolean = false
If the shuffle attribute is true then the delivery engine must randomize the order in which the choices are presented subject to the fixed attribute of the choice.

Attribute : maxAssociations [1]: integer = 1
The maximum number of associations that the candidate is allowed to make. If maxAssociations is 0 then there is no restriction. If maxAssociations is greater than 1 (or 0) then the interaction must be bound to a response with multiple cardinality.

Attribute : minAssociations [0..1]: integer = 0
The minimum number of associations that the candidate is required to make to form a valid response. If minAssociations is 0 then the candidate is not required to make any associations. minAssociations must be less than or equal to the limit imposed by maxAssociations.

Contains : simpleAssociableChoice [1..*]
An ordered set of choices.

A match interaction is a blockInteraction that presents candidates with two sets of choices and allows them to create associates between pairs of choices in the two sets, but not between pairs of choices in the same set. Further restrictions can still be placed on the allowable associations using the matchMax and matchGroup attributes of the choices.

The matchInteraction must be bound to a response variable with base-type directedPair and either single or multiple cardinality.

Attribute : shuffle [1]: boolean = false
If the shuffle attribute is true then the delivery engine must randomize the order in which the choices are presented within each set, subject to the fixed attribute of the choices themselves.

Attribute : maxAssociations [1]: integer = 1
The maximum number of associations that the candidate is allowed to make. If maxAssociations is 0 then there is no restriction. If maxAssociations is greater than 1 (or 0) then the interaction must be bound to a response with multiple cardinality.

Attribute : minAssociations [0..1]: integer = 0
The minimum number of associations that the candidate is required to make to form a valid response. If minAssociations is 0 then the candidate is not required to make any associations. minAssociations must be less than or equal to the limit imposed by maxAssociations.

Contains : simpleMatchSet [2]
The two sets of choices, the first set defines the source choices and the second set the targets.

Attribute : matchMax [1]: integer
The maximum number of choices this choice may be associated with. If matchMax is 0 then there is no restriction.

Attribute : matchMin [0..1]: integer = 0
The minimum number of choices this choice must be associated with to form a valid response. If matchMin is 0 then the candidate is not required to associate this choice with any others at all. matchMin must be less than or equal to the limit imposed by matchMax.

Contains : flowStatic [*]

associableChoice is a choice that contains flowStatic objects, it must not contain nested interactions.

Contains : simpleAssociableChoice [*]
An ordered set of choices for the set.

A gap match interaction is a blockInteraction that contains a number gaps that the candidate can fill from an associated set of choices. The candidate must be able to review the content with the gaps filled in context, as indicated by their choices.

The gapMatchInteraction must be bound to a response variable with base-type directedPair and either single or multiple cardinality, depending on the number of gaps. The choices represent the source of the pairing and gaps the targets. Each gap can have at most one choice associated with it. The maximum occurrence of the choices is controlled by the matchMax attribute of gapChoice.

Attribute : shuffle [1]: boolean = false
If the shuffle attribute is true then the delivery engine must randomize the order in which the choices are presented (not the gaps), subject to the fixed attribute of the choices themselves.

Contains : gapChoice [1..*]
An ordered list of choices for filling the gaps. There may be fewer choices than gaps if required.

Contains : blockStatic [1..*]
The content of the interaction is simply a piece of content that contains the gaps. If the block contains more than one gap then the interaction must be bound to a response with multiple cardinality.

gap is an inlineStatic element that must only appear within a gapMatchInteraction.

Attribute : required [0..1]: boolean = false
If true then this gap must be filled by the candidate in order to form a valid response to the interaction.

The choices that are used to fill the gaps in a gapMatchInteraction are either simple runs of text or single image objects, both derived from gapChoice.

Attribute : matchMax [1]: integer
The maximum number of choices this choice may be associated with. If matchMax is 0 there is no restriction.

Attribute : matchMin [0..1]: integer = 0
The minimum number of gaps this choice must be associated with to form a valid response. If matchMin is 0 then the candidate is not required to associate this choice with any gaps at all. matchMin must be less than or equal to the limit imposed by matchMax.

A simple run of text to be inserted into a gap by the user, may be subject to variable value substitution with printedVariable.

Contains : textOrVariable [*]

A gap image contains a single image object to be inserted into a gap by the candidate.

Attribute : objectLabel [0..1]: string
An optional label for the image object to be inserted.

Contains : object [1]

A inline choice is an inlineInteraction that presents the user with a set of choices, each of which is a simple piece of text. The candidate's task is to select one of the choices. Unlike the choiceInteraction, the delivery engine must allow the candidate to review their choice within the context of the surrounding text.

The inlineChoiceInteraction must be bound to a response variable with a baseType of identifier and single cardinality only.

Contains : inlineChoice [1..*]
An ordered list of the choices that are displayed to the user. The order is the order of the choices presented to the user unless shuffle is true.

Attribute : shuffle [1]: boolean = false
If the shuffle attribute is true then the delivery engine must randomize the order in which the choices are presented subject to the fixed attribute.

Attribute : required [0..1]: boolean = false
If true then a choice must be selected by the candidate in order to form a valid response to the interaction.

A simple run of text to be displayed to the user, may be subject to variable value substitution with printedVariable.

String interactions can be bound to numeric response variables, instead of strings, if desired.

If detailed information about a numeric response is required then the string interaction can be bound to a response variable with record cardinality. The resulting value contains the following fields:

• stringValue: the string, as typed by the candidate.
• floatValue: the numeric value of the string typed by the candidate, as a float.
• integerValue: the numeric value of the string typed by the candidate if no fractional digits or exponent were specified, otherwise NULL. An integer.
• leftDigits: the number of digits to the left of the point. An integer.
• rightDigits: the number of digits to the right of the point. An integer.
• ndp: the number of fractional digits specified by the candidate. If no exponent was given this is the same as rightDigits. An integer.
• nsf: the number of significant digits specified by the candidate. An integer.
• exponent: the integer exponent given by the candidate or NULL if none was specified.

Attribute : base [0..1]: integer = 10
If the string interaction is bound to a numeric response variable then the base attribute must be used to set the number base in which to interpret the value entered by the candidate.

Attribute : stringIdentifier [0..1]: identifier
If the string interaction is bound to a numeric response variable then the actual string entered by the candidate can also be captured by binding the interaction to a second response variable (of base-type string).

Attribute : expectedLength [0..1]: integer
The expectedLength attribute provides a hint to the candidate as to the expected overall length of the desired response. A Delivery Engine should use the value of this attribute to set the size of the response box, where applicable. This is not a validity constraint.

Attribute : patternMask [0..1]: string
If given, the pattern mask specifies a regular expression that the candidate's response must match in order to be considered valid. The regular expression language used is defined in Appendix F of [XML_SCHEMA2]. Care is needed to ensure that the format of the required input is clear to the candidate, especially when validity checking of responses is required for progression through a test. This could be done by providing an illustrative sample response in the prompt, for example.

Attribute : placeholderText [0..1]: string
In visual environments, string interactions are typically represented by empty boxes into which the candidate writes or types. However, in speech based environments it is helpful to have some placeholder text that can be used to vocalize the interaction. Delivery engines should use the value of this attribute (if provided) instead of their default placeholder text when this is required. Implementors should be aware of the issues concerning the use of default values described in the section on Response Variables.

A textEntry interaction is an inlineInteraction that obtains a simple piece of text from the candidate. Like inlineChoiceInteraction, the delivery engine must allow the candidate to review their choice within the context of the surrounding text.

The textEntryInteraction must be bound to a response variable with single cardinality only. The baseType must be one of string, integer, or float.

An extended text interaction is a blockInteraction that allows the candidate to enter an extended amount of text.

The extendedTextInteraction must be bound to a response variable with baseType of string, integer, or float. When bound to response variable with single cardinality a single string of text is required from the candidate. When bound to a response variable with multiple or ordered cardinality several separate text strings may be required, see maxStrings below.

Attribute : maxStrings [0..1]: integer
The maxStrings attribute is required when the interaction is bound to a response variable that is a container. A Delivery Engine must use the value of this attribute to control the maximum number of separate strings accepted from the candidate. When multiple strings are accepted, expectedLength applies to each string.

Attribute : minStrings [0..1]: integer = 0
The minStrings attribute specifies the minimum number separate (non-empty) strings required from the candidate to form a valid response. If minStrings is 0 then the candidate is not required to enter any strings at all. minStrings must be less than or equal to the limit imposed by maxStrings. If the interaction is not bound to a container then there is a special case in which minStrings may be 1. In this case the candidate must enter a non-empty string to form a valid response. More complex constraints on the form of the string can be controlled with the patternMask attribute.

Attribute : expectedLines [0..1]: integer
The expectedLines attribute provides a hint to the candidate as to the expected number of lines of input required. A Delivery Engine should use the value of this attribute to set the size of the response box, where applicable. This is not a validity constraint.

Attribute : format [0..1]: textFormat = plain
Used to control the format of the text entered by the candidate. See textFormat below. This attribute affects the way the value of the associated response variable should be interpreted by response processing engines and also controls the way it should be captured in the delivery engine.

plain
Indicates that the text to be entered by the candidate is plain text. This format is suitable for short unstructured responses. Delivery engines should preserve white-space characters in candidate input except where a response consists only of white-space characters, in which case it should be treated as an empty string (NULL).

preFormatted
Indicates that the text to be entered by the candidate is pre-formatted and should be rendered in a way consistent with the definition of pre in [XHTML]. Delivery engines must preserve white-space characters except where a response consists only of white-space characters, in which case it should be treated as an empty string (NULL).

xhtml
Indicates that the text to be entered by the candidate is structured text. The value of the response variable is text marked up in XHTML. The delivery engine should present an interface suitable for capturing structured text, this might be plain typed text interpreted with a set of simple text markup conventions such as those used in wiki page editors or a complete WYSIWYG editor.

The hottext interaction presents a set of choices to the candidate represented as selectable runs of text embedded within a surrounding context, such as a simple passage of text. Like choiceInteraction, the candidate's task is to select one or more of the choices, up to a maximum of maxChoices. The interaction is initialized from the defaultValue of the associated response variable, a NULL value indicating that no choices are selected (the usual case).

The hottextInteraction must be bound to a response variable with a baseType of identifier and single or multiple cardinality.

Attribute : maxChoices [1]: integer = 1
The maximum number of choices that can be selected by the candidate. If matchChoices is 0 there is no restriction. If maxChoices is greater than 1 (or 0) then the interaction must be bound to a response with multiple cardinality.

Attribute : minChoices [0..1]: integer = 0
The minimum number of choices that the candidate is required to select to form a valid response. If minChoices is 0 then the candidate is not required to select any choices. minChoices must be less than or equal to the limit imposed by maxChoices.

Contains : blockStatic [1..*]
The content of the interaction is simply a piece of content, such as a simple passage of text, that contains the hottext areas.

A hottext area is used within the content of an hottextInteraction to provide the individual choices. It must not contain any nested interactions or other hottext areas.

When a hottext choice is hidden (by the value of an associated template variable) the content of the choice must still be presented to the candidate as if it were simply part of the surrounding material. In the case of hottext, the effect of hiding the choice is simply to make the run of text unselectable by the candidate.

Contains : inlineStatic [*]

Some of the graphic interactions involve images with specially defined areas or hotspots.

Attribute : shape [1]: shape
The shape of the hotspot.

Attribute : coords [1]: coords
The size and position of the hotspot, interpreted in conjunction with the shape.

Attribute : hotspotLabel [0..1]: string256
The alternative text for this (hot) area of the image, if specified it must be treated in the same way as alternative text for img. For hidden hotspots this label is ignored.

Attribute : matchMax [1]: integer
The maximum number of choices this choice may be associated with. If matchMax is 0 there is no restriction.

Attribute : matchMin [0..1]: integer = 0
The minimum number of choices this choice must be associated with to form a valid response. If matchMin is 0 then the candidate is not required to associate this choice with any others at all. matchMin must be less than or equal to the limit imposed by matchMax.

Contains : object [1]
Each graphical interaction has an associated image which is given as an object that must be of an image type, as specified by the type attribute.

A hotspot interaction is a graphical interaction with a corresponding set of choices that are defined as areas of the graphic image. The candidate's task is to select one or more of the areas (hotspots). The hotspot interaction should only be used when the spacial relationship of the choices with respect to each other (as represented by the graphic image) is important to the needs of the item. Otherwise, choiceInteraction should be used instead with separate material for each option.

The delivery engine must clearly indicate the selected area(s) of the image and may also indicate the unselected areas as well. Interactions with hidden hotspots are achieved with the selectPointInteraction.

The hotspot interaction must be bound to a response variable with a baseType of identifier and single or multiple cardinality.

Attribute : maxChoices [1]: integer = 1
The maximum number of choices that the candidate is allowed to select. If maxChoices is 0 there is no restriction. If maxChoices is greater than 1 (or 0) then the interaction must be bound to a response with multiple cardinality.

Attribute : minChoices [0..1]: integer = 0
The minimum number of choices that the candidate is required to select to form a valid response. If minChoices is 0 then the candidate is not required to select any choices. minChoices must be less than or equal to the limit imposed by maxChoices.

Contains : hotspotChoice [1..*] {ordered}
The hotspots that define the choices that can be selected by the candidate. If the delivery system does not support pointer-based selection then the order in which the choices are given must be the order in which they are offered to the candidate for selection. For example, the 'tab order' in simple keyboard navigation. If hotspots overlap then those listed first hide overlapping hotspots that appear later. The default hotspot, if defined, must appear last.

Like hotspotInteraction, a select point interaction is a graphic interaction. The candidate's task is to select one or more points. The associated response may have an areaMapping that scores the response on the basis of comparing it against predefined areas but the delivery engine must not indicate these areas of the image. Only the actual point(s) selected by the candidate shall be indicated.

The select point interaction must be bound to a response variable with a baseType of point and single or multiple cardinality.

Attribute : maxChoices [1]: integer = 1
This attribute is interpreted as the maximum number of points that the candidate is allowed to select. If maxChoices is 0 there is no restriction. If maxChoices is greater than 1 (or 0) then the interaction must be bound to a response with multiple cardinality.

Attribute : minChoices [0..1]: integer = 0
The minimum number of points that the candidate is required to select to form a valid response. If minChoices is 0 then the candidate is not required to select any points. minChoices must be less than or equal to the limit imposed by maxChoices.

A graphic order interaction is a graphic interaction with a corresponding set of choices that are defined as areas of the graphic image. The candidate's task is to impose an ordering on the areas (hotspots). The order hotspot interaction should only be used when the spacial relationship of the choices with respect to each other (as represented by the graphic image) is important to the needs of the item. Otherwise, orderInteraction should be used instead with separate material for each option.

The delivery engine must clearly indicate all defined area(s) of the image.

The order hotspot interaction must be bound to a response variable with a baseType of identifier and ordered cardinality.

Contains : hotspotChoice [1..*]
The hotspots that define the choices that are to be ordered by the candidate. If the delivery system does not support pointer-based selection then the order in which the choices are given must be the order in which they are offered to the candidate for selection. For example, the 'tab order' in simple keyboard navigation.

Attribute : minChoices [0..1]: integer
The minimum number of choices that the candidate must select and order to form a valid response to the interaction. If specified, minChoices must be 1 or greater but must not exceed the number of choices available. If unspecified, all of the choices must be ordered and maxChoices is ignored.

Attribute : maxChoices [0..1]: integer
The maximum number of choices that the candidate may select and order when responding to the interaction. Used in conjunction with minChoices, if specified, maxChoices must be greater than or equal to minChoices and must not exceed the number of choices available. If unspecified, all of the choices may be ordered.

A graphic associate interaction is a graphic interaction with a corresponding set of choices that are defined as areas of the graphic image. The candidate's task is to associate the areas (hotspots) with each other. The graphic associate interaction should only be used when the graphical relationship of the choices with respect to each other (as represented by the graphic image) is important to the needs of the item. Otherwise, associateInteraction should be used instead with separate Material for each option.

The delivery engine must clearly indicate all defined area(s) of the image.

The associateHotspotInteraction must be bound to a response variable with base-type pair and either single or multiple cardinality.

Attribute : maxAssociations [1]: integer = 1
The maximum number of associations that the candidate is allowed to make. If maxAssociations is 0 there is no restriction. If maxAssociations is greater than 1 (or 0) then the interaction must be bound to a response with multiple cardinality.

Contains : associableHotspot [1..*]
The hotspots that define the choices that are to be associated by the candidate. If the delivery system does not support pointer-based selection then the order in which the choices are given must be the order in which they are offered to the candidate for selection. For example, the 'tab order' in simple keyboard navigation.

A graphic gap-match interaction is a graphical interaction with a set of gaps that are defined as areas (hotspots) of the graphic image and an additional set of gap choices that are defined outside the image. The candidate must associate the gap choices with the gaps in the image and be able to review the image with the gaps filled in context, as indicated by their choices. Care should be taken when designing these interactions to ensure that the gaps in the image are a suitable size to receive the required gap choices. It must be clear to the candidate which hotspot each choice has been associated with. When associated, choices must appear wholly inside the gaps if at all possible and, where overlaps are required, should not hide each other completely. If the candidate indicates the association by positioning the choice over the gap (e.g., drag and drop) the system should 'snap' it to the nearest position that satisfies these requirements.

The graphicGapMatchInteraction must be bound to a response variable with base-type directedPair and multiple cardinality. The choices represent the source of the pairing and the gaps in the image (the hotspots) the targets. Unlike the simple gapMatchInteraction, each gap can have several choices associated with it if desired, furthermore, the same choice may be associated with an associableHotspot multiple times, in which case the corresponding directed pair appears multiple times in the value of the response variable.

Contains : gapImg [1..*]
An ordered list of choices for filling the gaps. There may be fewer choices than gaps if required.

Contains : associableHotspot [1..*]
The hotspots that define the gaps that are to be filled by the candidate. If the delivery system does not support pointer-based selection then the order in which the gaps is given must be the order in which they are offered to the candidate for selection. For example, the 'tab order' in simple keyboard navigation. The default hotspot must not be defined.

The position object interaction consists of a single image which must be positioned on another graphic image (the stage) by the candidate. Like selectPointInteraction, the associated response may have an areaMapping that scores the response on the basis of comparing it against predefined areas but the delivery engine must not indicate these areas of the stage. Only the actual position(s) selected by the candidate shall be indicated.

The position object interaction must be bound to a response variable with a baseType of point and single or multiple cardinality. The point records the coordinates, with respect to the stage, of the center point of the image being positioned.

Attribute : centerPoint [0..2]: integer
The centerPoint attribute defines the point on the image being positioned that is to be treated as the center as an offset from the top-left corner of the image in horizontal, vertical order. By default this is the center of the image's bounding rectangle.

The stage on which the image is to be positioned may be shared amongst several position object interactions and is therefore defined in a class of its own: positionObjectStage.

Attribute : maxChoices [1]: integer = 1
The maximum number of positions (on the stage) that the image can be placed. If matchChoices is 0 there is no limit. If maxChoices is greater than 1 (or 0) then the interaction must be bound to a response with multiple cardinality.

Attribute : minChoices [0..1]: integer
The minimum number of positions that the image must be placed to form a valid response to the interaction. If specified, minChoices must be 1 or greater but must not exceed the limit imposed by maxChoices.

Contains : object [1]
The image to be positioned on the stage by the candidate.

Contains : object [1]
The image to be used as a stage onto which individual positionObjectInteractions allow the candidate to place their objects.

Contains : positionObjectInteraction [1..*]

The slider interaction presents the candidate with a control for selecting a numerical value between a lower and upper bound. It must be bound to a response variable with single cardinality with a base-type of either integer or float.

Attribute : lowerBound [1]: float
If the associated response variable is of type integer then the lowerBound must be rounded down to the greatest integer less than or equal to the value given.

Attribute : upperBound [1]: float
If the associated response variable is of type integer then the upperBound must be rounded up to the least integer greater than or equal to the value given.

Attribute : step [0..1]: integer
The steps that the control moves in. For example, if the lowerBound and upperBound are [0,10] and step is 2 then the response would be constrained to the set of values {0,2,4,6,8,10}. If bound to an integer response the default step is 1, otherwise the slider is assumed to operate on an approximately continuous scale.

Attribute : stepLabel [0..1]: boolean = false
By default, sliders are labeled only at their ends. The stepLabel attribute controls whether or not each step on the slider should also be labeled. It is unlikely that delivery engines will be able to guarantee to label steps so this attribute should be treated only as request.

Attribute : orientation [0..1]: orientation
The orientation attribute provides a hint to rendering systems that the slider is being used to indicate the value of a quantity with an inherent vertical or horizontal interpretation. For example, an interaction that is used to indicate the value of height might set the orientation to vertical to indicate that rendering it horizontally could spuriously increase the difficulty of the item.

Attribute : reverse [0..1]: boolean
The reverse attribute provides a hint to rendering systems that the slider is being used to indicate the value of a quantity for which the normal sense of the upper and lower bounds is reversed. For example, an interaction that is used to indicate a depth below sea level might specify both a vertical orientation and set reverse.

Note that a slider interaction does not have a default or initial position except where specified by a default value for the associated response variable. The currently selected value, if any, must be clearly indicated to the candidate.

The media interaction allows more control over the way the candidate interacts with a time-based media object and allows the number of times the media object was experienced to be reported in the value of the associated response variable, which must be of base-type integer and single cardinality.

Attribute : autostart [1]: boolean
The autostart attribute determines if the media object should begin as soon as the candidate starts the attempt (true) or if the media object should be started under the control of the candidate (false).

Attribute : minPlays [0..1]: integer = 0
The minPlays attribute indicates that the media object should be played a minimum number of times by the candidate. The techniques required to enforce this will vary from system to system, in some systems it may not be possible at all. By default there is no minimum. Failure to play the media object the minimum number of times constitutes an invalid response.

Attribute : maxPlays [0..1]: integer = 0
The maxPlays attribute indicates that the media object can be played at most maxPlays times—it must not be possible for the candidate to play the media object more than maxPlay times. A value of 0 (the default) indicates that there is no limit.

Attribute : loop [0..1]: boolean = false
The loop attribute is used to set continuous play mode. In continuous play mode, once the media object has started to play it should play continuously (subject to maxPlays).

Contains : object [1]
The media object itself.

The drawing interaction allows the candidate to use a common set of drawing tools to modify a given graphical image (the canvas). It must be bound to a response variable with base-type file and single cardinality. The result is a file in the same format as the original image.

Contains : object [1]
The image that acts as the canvas on which the drawing takes place is given as an object which must be of an image type, as specified by the type attribute.

The upload interaction allows the candidate to upload a pre-prepared file representing their response. It must be bound to a response variable with base-type file and single cardinality.

Attribute : type [0..1]: mimeType
The expected mime-type of the uploaded file.

The custom interaction provides an opportunity for extensibility of this specification to include support for interactions not currently documented.

The end attempt interaction is a special type of interaction which allows item authors to provide the candidate with control over the way in which the candidate terminates an attempt. The candidate can use the interaction to terminate the attempt (triggering response processing) immediately, typically to request a hint. It must be bound to a response variable with base-type boolean and single cardinality.

If the candidate invokes response processing using an endAttemptInteraction then the associated response variable is set to true. If response processing is invoked in any other way, either through a different endAttemptInteraction or through the default method for the delivery engine, then the associated response variable is set to false. The default value of the response variable is always ignored.

Attribute : title [1]: string
The string that should be displayed to the candidate as a prompt for ending the attempt using this interaction. This should be short, preferably one word. A typical value would be "Hint". For example, in a graphical environment it would be presented as the label on a button that, when pressed, ends the attempt.

Attribute : template [0..1]: uri
If a template identifier is given it may be used to locate an externally defined responseProcessing template. The rules obtained from the external template may be used instead of the rules defined within the item itself, though if both are given the internal rules are still preferred.

Attribute : templateLocation [0..1]: uri
In practice, the template attribute may well contain a URN or the URI of a template stored on a remote web server, such as the standard response processing templates defined by this specification. When processing an assessmentItem tools working offline will not be able to obtain the template from a URN or remote URI. The templateLocation attribute provides an alternative URI, typically a relative URI to be resolved relative to the location of the assessmentItem itself, that can be used to obtain a copy of the response processing template. If a delivery system is able to determine the correct behavior from the template identifier alone the templateLocation should be ignored. For example, a delivery system may have built-in procedures for handling the standard templates defined above.

Contains : responseRule [*]

The mapping from values assigned to responses variables by the candidate onto appropriate values for the item's outcome variables is achieved through a number of rules.

Figure 8.2 Response Processing.

A response rule is either a responseCondition, a simple action or a responseProcessingFragment. Response rules define the light-weight programming language necessary for deriving outcomes from responses (i.e., scoring). Note that this programming language contains a minimal number of control structures, more complex scoring rules must be coded in other languages and referred to using a customOperator.

Contains : responseIf [1]

Contains : responseElseIf [*]

Contains : responseElse [0..1]

If the expression given in a responseIf or responseElseIf evaluates to true then the sub-rules contained within it are followed and any following responseElseIf or responseElse parts are ignored for this response condition.

If the expression given in a responseIf or responseElseIf does not evaluate to true then consideration passes to the next responseElseIf or, if there are no more responseElseIf parts then the sub-rules of the responseElse are followed (if specified).

Contains : expression [1]

Contains : responseRule [*]

A responseIf part consists of an expression which must have an effective baseType of boolean and single cardinality. For more information about the runtime data model employed see Expressions. It also contains a set of sub-rules. If the expression is true then the sub-rules are processed, otherwise they are skipped (including if the expression is NULL) and the following responseElseIf or responseElse parts (if any) are considered instead.

Contains : expression [1]

Contains : responseRule [*]

responseElseIf is defined in an identical way to responseIf.

Contains : responseRule [*]

Attribute : identifier [1]: identifier
The outcome variable to be set.

Contains : expression [1]
An expression which must have an effective baseType and cardinality that matches the base-type and cardinality of the outcome variable being set.

The setOutcomeValue rule sets the value of an outcome variable to the value obtained from the associated expression. An outcome variable can be updated with reference to a previously assigned value, in other words, the outcome variable being set may appear in the expression where it takes the value previously assigned to it.

Special care is required when using the numeric base-types because floating point values can not be assigned to integer variables and vice-versa. The truncate, round, or integerToFloat operators must be used to achieve numeric type conversion.

The lookupOutcomeValue rule sets the value of an outcome variable to the value obtained by looking up the value of the associated expression in the lookupTable associated with the outcome's declaration.

Attribute : identifier [1]: identifier
The outcome variable to be set.

Contains : expression [1]
An expression which must have single cardinality and an effective baseType of either integer, float , or duration. Integer type is required when the associated table is a matchTable.

The exit response rule terminates response processing immediately (for this invocation).

Modal feedback is shown to the candidate directly following response processing. The value of an outcome variable is used in conjunction with the showHide and identifier attributes to determine whether or not the feedback is shown in a similar way to feedbackElement.

Attribute : outcomeIdentifier [1]: identifier

Attribute : showHide [1]: showHide

Attribute : identifier [1]: identifier

Attribute : title [0..1]: string
Delivery engines are not required to present the title to the candidate but may do so, for example as the title of a modal pop-up window.

Contains : flowStatic [*]
The content of the modalFeedback must not contain any interactions.

Template declarations declare item variables that are to be used specifically for the purposes of cloning items. They can have their value set only during templateProcessing. They are referred to within the itemBody in order to individualize the clone and possibly also within the responseProcessing rules if the cloning process affects the way the item is scored.

Template variables are instantiated as part of an item session. Their values are initialized during templateProcessing and thereafter behave as constants within the session.

Attribute : paramVariable [0..1]: boolean = false
This attribute determines whether or not the template variable's value should be substituted for object parameter values that match its name. See param for more information.

Attribute : mathVariable [0..1]: boolean = false
This attribute determines whether or not the template variable's value should be substituted for identifiers that match its name in MathML expressions. See Combining Template Variables and MathML for more information.

Attribute : templateIdentifier [1]: identifier
The identifier of a template variable that must have a base-type of identifier and be of either single or multiple cardinality. The visibility of the templateElement is controlled by the value of the variable.

Attribute : showHide [1]: showHide = show

Attribute : identifier [1]: identifier

The showHide and identifier attributes determine how the visibility of the templateElement is controlled in the same way as the similarly named showHide and identifier attributes of feedbackElement.

A template element must not contain any interactions, either directly or indirectly.

Contains : blockStatic [*]

Contains : inlineStatic [*]

The type used for attributes of integer type that may be replaced with the value of a template variable of base type integer and single cardinality.

The type used for attributes of float type that may be replaced with the value of a template variable of base type float and single cardinality.

The type used for attributes of string type that may be replaced with the value of a template variable of base type string and single cardinality.

When template references are bound to strings (using the mandatory binding described above) there is a potential ambiguity. Therefore, if a string attribute appears to be a reference to a template variable but there is no variable with the given name it should be treated simply as string value.

Contains : templateRule [1..*]
Template processing consists of one or more templateRules that are followed by the cloning engine or delivery system in order to assign values to the template variables. Template processing is identical in form to responseProcessing except that the purpose is to assign values to template variables, not outcome variables.

A template rule is either a templateCondition or a simple action. Template rules define the light-weight programming language necessary for creating cloned items. Note that this programming language contains a minimal number of control structures, more complex cloning rules are outside the scope of this specification.

An expression used in a templateRule must not refer to the value of a response variable or outcome variable. It may only refer to the values of the template variables.

Contains : templateIf [1]

Contains : templateElseIf [*]

Contains : templateElse [0..1]

If the expression given in the templateIf or templateElseIf evaluates to true then the sub-rules contained within it are followed and any following templateElseIf or templateElse parts are ignored for this template condition.

If the expression given in the templateIf or templateElseIf does not evaluate to true then consideration passes to the next templateElseIf or, if there are no more templateElseIf parts then the sub-rules of the templateElse are followed (if specified).

Contains : expression [1]

Contains : templateRule [*]

A templateIf part consists of an expression which must have an effective baseType of boolean and single cardinality. For more information about the runtime data model employed see Expressions. It also contains a set of sub-rules. If the expression is true then the sub-rules are processed, otherwise they are skipped (including if the expression is NULL) and the following templateElseIf or templateElse parts (if any) are considered instead.

Contains : expression [1]

Contains : templateRule [*]

templateElseIf is defined in an identical way to templateIf.

Contains : templateRule [*]

Attribute : identifier [1]: identifier
The template variable to be set.

Contains : expression [1]
An expression which must have an effective baseType and cardinality that matches the base-type and cardinality of the template variable being set.

The setTemplateValue rule sets the value of a template variable to the value obtained from the associated expression. A template variable can be updated with reference to a previously assigned value, in other words, the template variable being set may appear in the expression where it takes the value previously assigned to it.

Attribute : identifier [1]: identifier
The response variable to have its correct value set.

Contains : expression [1]

Attribute : identifier [1]: identifier
The response variable or outcome variable to have its default value set.

Contains : expression [1]

The exit template rule terminates template processing immediately.

A test is a group of assessmentItems with an associated set of rules that determine which of the items the candidate sees, in what order, and in what way the candidate interacts with them. The rules describe the valid paths through the test, when responses are submitted for response processing and when (if at all) feedback is to be given.

Attribute : identifier [1]: string
The principle identifier of the test. This identifier must have a corresponding entry in the test's meta-data. See Meta-data and Usage Data for more information.

Attribute : title [1]: string
The title of an assessmentTest is intended to enable the test to be selected outside of any test session. Therefore, delivery engines may reveal the title to candidates at any time, but are not required to do so.

Attribute : toolName [0..1]: string256
The tool name attribute allows the tool creating the test to identify itself. Other processing systems may use this information to interpret the content of application specific data, such as labels on the elements of the test rubric.

Attribute : toolVersion [0..1]: string256
The tool version attribute allows the tool creating the test to identify its version. This value must only be interpreted in the context of the toolName.

Contains : outcomeDeclaration [*]
Each test has an associated set of outcomes. The values of these outcomes are set by the test's outcomeProcessing rules.

Contains : timeLimits [0..1]
Optionally controls the amount of time a candidate is allowed for the entire test.

Contains : testPart [1..*]
Each test is divided into one or more parts which may in turn be divided into sections, sub-sections, and so on. A testPart represents a major division of the test and is used to control the basic mode parameters that apply to all sections and sub-sections within that part.

Contains : outcomeProcessing [0..1]
The set of rules used for calculating the values of the test outcomes.

Contains : testFeedback [*]
Contains the test-level feedback controlled by the test outcomes.

linear

nonlinear

The navigation mode determines the general paths that the candidate may take. A testPart in linear mode restricts the candidate to attempt each item in turn. Once the candidate moves on they are not permitted to return. A testPart in nonlinear mode removes this restriction - the candidate is free to navigate to any item in the test at any time. Test delivery systems are free to implement their own user interface elements to facilitate navigation provided they honor the navigation mode currently in effect. A test delivery system may implement nonlinear mode simply by providing a method to step forward or backwards through the test part.

individual

simultaneous

The submission mode determines when the candidate's responses are submitted for response processing. A testPart in individual mode requires the candidate to submit their responses on an item-by-item basis. In simultaneous mode the candidate's responses are all submitted together at the end of the testPart.

The choice of submission mode determines the states through which each item's session can pass during the test. In simultaneous mode, response processing cannot take place until the testPart is complete so each item session passes between the interacting and suspended states only. By definition the candidate can take one and only one attempt at each item and feedback cannot be seen during the test. Whether or not candidates can return to review their responses and/or any item-level feedback after the test, is outside the scope of this specification. Simultaneous mode is typical of paper-based tests.

In individual mode, response processing may take place during the test and the item session may pass through any of the states described in Items, subject to the itemSessionControl settings in force. Care should be taken when designing user interfaces for systems that support nonlinear navigation mode in combination with individual submission. With this combination candidates may change their responses for an item and then leave it in the suspended state by navigating to a different item in the same part of the test. Test delivery systems need to make it clear to candidates that there are unsubmitted responses (akin to unsaved changes in a traditional document editing system) at the end of the test part. A test delivery system may force candidates to submit or discard such responses before moving to a different item in individual mode if this is more appropriate.

Attribute : identifier [1]: identifier
The identifier of the test part must be unique within the test and must not be the identifier of any assessmentSection or assessmentItemRef.

Attribute : navigationMode [1]: navigationMode

Attribute : submissionMode [1]: submissionMode

Contains : preCondition [*]
An optional set of conditions evaluated during the test, that determine if this part is to be skipped.

Contains : branchRule [*]
An optional set of rules, evaluated during the test, for setting an alternative target as the next part of the test.

Contains : itemSessionControl [0..1]
Parameters used to control the allowable states of each item session in this part. These values may be overridden at section and item level.

Contains : timeLimits [0..1]
Optionally controls the amount of time a candidate is allowed for this part of the test.

Contains : assessmentSection [1..*]
The items contained in each testPart are arranged into sections and sub-sections.

Contains : testFeedback [*]
Test-level feedback specific to this part of the test.

The selection class specifies the rules used to select the child elements of a section for each test session. If no selection rules are given we assume that all elements are to be selected.

Attribute : select [1]: integer
The number of child elements to be selected. Sub-sections always count as 1, regardless of how many child elements they have and whether or not they are visible. The number of children to select may exceed the number of child elements defined only if withReplacement is true.

Attribute : withReplacement [0..1]: boolean = false
When selecting child elements each element is normally eligible for selection once only. In other words, when selecting 3 elements from {A,B,C,D} the possible outcomes are {A,B,C}, {A,B,D}, {A,C,D}, and {B,C,D}. By setting withReplacement to true each element becomes eligible for selection multiple times. Selecting 3 nodes from {A,B,C,D} can then result in combinations such as {A,A,A}, {A,A,B} and so on.

The selection class also provides an opportunity for extensions to this specification to include support for more complex selection algorithms.

The ordering class specifies the rule used to arrange the child elements of a section following selection. If no ordering rule is given we assume that the elements are to be ordered in the order in which they are defined.

Attribute : shuffle [1]: boolean = false
If true causes the order of the child elements to be randomized, if false uses the order in which the child elements are defined.

A sub-section is always treated as a single block for selection but the way it is treated when shuffling depends on its visibility. A visible sub-section is always treated as a single block but an invisible sub-section is only treated as a single block if its keepTogether attribute is true. Otherwise, the child elements of the invisible sub-section are mixed into the parent's selection prior to shuffling.

The ordering class also provides an opportunity for extensions to this specification to include support for more complex ordering algorithms.

Sections group together individual item references and/or sub-sections. A number of common parameters are shared by both types of child element.

Attribute : identifier [1]: identifier
The identifier of the section or item reference must be unique within the test and must not be the identifier of any testPart.

Attribute : required [0..1]: boolean = false
If a child element is required it must appear (at least once) in the selection. It is in error if a section contains a selection rule that selects fewer child elements than the number of required elements it contains.

Attribute : fixed [0..1]: boolean = false
If a child element is fixed it must never be shuffled. When used in combination with a selection rule fixed elements do not have their position fixed until after selection has taken place. For example, selecting 3 elements from {A,B,C,D} without replacement might result in the selection {A,B,C}. If the section is subject to shuffling but B is fixed then permutations such as {A,C,B} are not allowed whereas permutations like {C,B,A} are.

Contains : preCondition [*]
An optional set of conditions evaluated during the test, that determine if the item or section is to be skipped (in nonlinear mode, pre-conditions are ignored).

Contains : branchRule [*]
An optional set of rules, evaluated during the test, for setting an alternative target as the next item or section (in nonlinear mode, branch rules are ignored).

Contains : itemSessionControl [0..1]
Parameters used to control the allowable states of each item session (may be overridden at sub-section or item level).

Contains : timeLimits [0..1]
Optionally controls the amount of time a candidate is allowed for this item or section.

Attribute : title [1]: string
The title of the section is intended to enable the section to be selected in situations where the contents of the section are not available, for example when a candidate is browsing a test. Therefore, delivery engines may reveal the title to candidates at any time during the test but are not required to do so.

Attribute : visible [1]: boolean
A visible section is one that is identifiable by the candidate. For example, delivery engines might provide a hierarchical view of the test to aid navigation. In such a view, a visible section would be a visible node in the hierarchy. Conversely, an invisible section is one that is not visible to the candidate—the child elements of an invisible section appear to the candidate as if they were part of the parent section (or testPart). The visibility of a section does not affect the visibility of its child elements. The visibility of each section is determined solely by the value of its own visible attribute.

Attribute : keepTogether [0..1]: boolean = true
An invisible section with a parent that is subject to shuffling can specify whether or not its children, which will appear to the candidate as if they were part of the parent, are shuffled as a block or mixed up with the other children of the parent section.

Contains : selection [0..1]
The rules used to select which children of the section are to be used for each instance of the test.

Contains : ordering [0..1]
The rules used to determine the order in which the children of the section are to be arranged for each instance of the test.

Each child section has its own selection and ordering rules followed before those of its parent. A child section may shuffle the order of its own children while still requiring that they are kept together when shuffling the parent section.

Contains : rubricBlock [*]
Section rubric is presented to the candidate with each item contained (directly or indirectly) by the section. As sections are nestable the rubric presented for each item is the concatenation of the rubric blocks from the top-most section down to the item's immediately enclosing section.

Contains : sectionPart [*]
An empty section is assumed to be one that uses a selection extension mechanism to describe its contents.

Items are incorporated into the test by reference and not by direct aggregation. Note that the identifier of the reference need not have any meaning outside the test. In particular it is not required to be unique in the context of any catalog, or be represented in the item's meta-data. The syntax of this identifier is more restrictive than that of the identifier attribute of the assessmentItem itself.

Attribute : href [1]: uri
The uri used to refer to the item's file (e.g., elsewhere in the same content package). There is no requirement that this be unique. A test may refer to the same item multiple times within a test. Note however that each reference must have a unique identifier.

Attribute : category [*]: identifier
Items can optionally be assigned to one or more categories. Categories are used to allow custom sets of item outcomes to be aggregated during outcomes processing.

Contains : variableMapping [*]
Variable mappings are used to alter the name of an item outcome for the purposes of this test.

Contains : weight [*]
Weights allow custom values to be defined for scaling an item's outcomes.

Contains : templateDefault [*]
A template default is used to alter the default value of a template variable declared by the item based on an expression evaluated at test-level. See templateDefault for more information.

The contribution of an individual item score to an overall test score typically varies from test to test. The score of the item is said to be weighted. Weights are defined as part of each reference to an item (assessmentItemRef) within a test.

Attribute : identifier [1]: identifier
An item can have any number of weights, each one is given an identifier that is used to refer to the weight in outcomes processing. (See the variable and testVariables definitions.)

Attribute : value [1]: float
Weights are floating point values. Weights can be applied to outcome variables of base type float or integer. The weight is applied at the time the variable's value is evaluated during outcomes processing. The result is always treated as having base type float even if the variable itself was declared as being of base type integer.

Variable mappings allow outcome variables declared with the name sourceIdentifier in the corresponding item to be treated as if they were declared with the name targetIdentifier during outcomeProcessing. Use of variable mappings allows more control over the way outcomes are aggregated when using testVariables.

Attribute : sourceIdentifier [1]: identifier

Attribute : targetIdentifier [1]: identifier

The default value of a template variable in an item can be overridden based on the test context in which the template is instantiated. The value is obtained by evaluating an expression defined within the reference to the item at test level and which may therefore depend on the values of variables taken from other items in the test or from outcomes defined at test level itself.

For consistent results it is vital that the expression is evaluated at the correct time. When the assessmentItemRef occurs in a testPart navigated in linear mode the expression is evaluated immediately prior to the start of the first attempt, after any pre-conditions are evaluated and acted upon but before the templateProcessing rules of the item itself are followed. In nonlinear mode the expression is evaluated at the start of the testPart. In both cases, the timing is unaffected by the submissionMode in effect. Care needs to be taken to ensure that values of response variables are not used before they have been submitted and that outcome variables are not used before their values have been set by the corresponding response or outcomes processing steps.

Attribute : templateIdentifier [1]: identifier
The identifier of the template variable affected.

Contains : expression [1]
An expression which must result in a value with baseType and cardinality matching the declaration of the associated variable's templateDeclaration.

The facility of overriding template defaults allows item templates to be linked to other items (or templates) within a test. A candidate response from one item can be used directly to affect the presentation or even the behavior of an item presented after it. However once the template is instantiated it operates independently—there is no dynamic link created between the items and no concept of a shared variable space between them.

Attribute : minTime [0..1]: duration

Attribute : maxTime [0..1]: duration

In the context of a specific assessmentTest an item, or group of items, may be subject to a time constraint. This specification supports both minimum and maximum time constraints. The controlled time for a single item is simply the duration of the item session as defined by the built-in response variable duration. For assessmentSections, testParts and whole assessmentTests the time limits relate to the durations of all the item sessions plus any other time spent navigating that part of the test. In other words, the time includes time spent in states where no item is being interacted with, such as dedicated navigation screens.

Minimum times are applicable to assessmentSections and assessmentItems only when linear navigation mode is in effect.

Outcome processing takes place each time the candidate submits the responses for an item (when in individual submission mode) or a group of items (when in simultaneous submission mode). It happens after any (item level) response processing triggered by the submission. The values of the test's outcome variables are always reset to their defaults prior to carrying out the instructions described by the outcomeRules. Because outcome processing happens each time the candidate submits responses the resulting values of the test-level outcomes may be used to activate test-level feedback during the test or to control the behavior of subsequent parts through the use of preConditions and branchRules.

The structure of outcome processing is similar to that of responseProcessing.

Contains : outcomeRule [*]

Contains : outcomeIf [1]

Contains : outcomeElseIf [*]

Contains : outcomeElse [0..1]

If the expression given in the outcomeIf or outcomeElseIf evaluates to true then the sub-rules contained within it are followed and any following outcomeElseIf or outcomeElse parts are ignored for this outcome condition.

If the expression given in the outcomeIf or outcomeElseIf does not evaluate to true then consideration passes to the next outcomeElseIf or, if there are no more outcomeElseIf parts then the sub-rules of the outcomeElse are followed (if specified).

Contains : expression [1]

Contains : outcomeRule [*]

A outcomeIf part consists of an expression which must have an effective baseType of boolean and single cardinality. For more information about the runtime data model employed see Expressions. It also contains a set of sub-rules. If the expression is true then the sub-rules are processed, otherwise they are skipped (including if the expression is NULL) and the following outcomeElseIf or outcomeElse parts (if any) are considered instead.

Contains : expression [1]

Contains : outcomeRule [*]

outcomeElseIf is defined in an identical way to outcomeIf.

Contains : outcomeRule [*]

Attribute : access [1]: testFeedbackAccess
Test feedback is shown to the candidate either directly following outcome processing (during the test) or at the end of the testPart or assessmentTest as appropriate (referred to as atEnd).

The value of an outcome variable is used in conjunction with the showHide and identifier attributes to determine whether or not the feedback is actually shown in a similar way to feedbackElement.

Attribute : outcomeIdentifier [1]: identifier

Attribute : showHide [1]: showHide

Attribute : identifier [1]: identifier

Attribute : title [0..1]: string
Delivery engines are not required to present the title to the candidate but may do so, for example as the title of a modal pop-up window or sub-heading in a combined report.

Contains : flowStatic [*]
The content of the testFeedback must not contain any interactions.

atEnd

during

A preCondition is a simple expression attached to an assessmentSection or assessmentItemRef that must evaluate to true if the item is to be presented. Pre-conditions are evaluated at the time the associated item, section, or testPart is to be attempted by the candidate, during the test. They differ from rules for selection and ordering (see Test Structure) which are followed at or before the start of the test.

If the expression evaluates to false, or has a NULL value, the associated item or section is skipped.

Contains : expression [1]

A branch-rule is a simple expression attached to an assessmentItemRef, assessmentSection or testPart that is evaluated after the item, section, or part has been presented to the candidate. If the expression evaluates to true the test jumps forward to the item, section, or part referred to by the target identifier. In the case of an item or section, the target must refer to an item or section in the same testPart that has not yet been presented. For testParts, the target must refer to another testPart.

[Comment] The above definition restricts the navigation paths through a linear test part to being trees. In other words, cycles are not allowed. In most cases, repetition can be achieved by using a section that selects withReplacement up to a suitable upper bound of repetition in combination with a preCondition or branchRule that terminates the section early when (or if) a certain outcome has been achieved. (This technique might be used in conjunction with one or more Item Templates to achieve drill and practice, for example.) However, unbounded repetition is not supported. Comments are sought on whether this approach is too restrictive.

Attribute : target [1]: identifier
The following values are reserved and have special meaning when used as a target identifier: EXIT_SECTION jumps over all the remaining children of the current section to the item (or section) immediately following it; EXIT_TESTPART finishes the current testPart immediately and EXIT_TEST finishes the entire assessmentTest immediately.

Contains : expression [1]

Expressions are used to assign values to item variables and to control conditional actions in response and template processing.

An expression can be a simple reference to the value of an itemVariable, a constant value from one of the value sets defined by baseTypes or a hierarchical expression operator. Like itemVariables, each expression can also have the special value NULL.

Attribute : baseType [1]: baseType
The base-type of the value.

The simplest expression returns a single value from the set defined by the given baseType.

Attribute : identifier [1]: identifier

This expression looks up the value of an itemVariable that has been declared in a corresponding variableDeclaration or is one of the built-in variables. The result has the base-type and cardinality declared for the variable subject to the type promotion of weighted outcomes (see below).

During outcomes processing, values taken from an individual item session can be looked up by prefixing the name of the item variable with the identifier assigned to the item in the assessmentItemRef, separated by a period character. For example, to obtain the value of the SCORE variable in the item referred to as Q01 you would use a variable instance with identifier Q01.SCORE.

When looking up the value of a response variable it always takes the value assigned to it by the candidate's last submission. Unsubmitted responses are not available during expression evaluation.

The value of an item variable taken from an item instantiated multiple times from the same assessmentItemRef (through the use of selection withReplacement) is taken from the last instance submitted if submission is simultaneous, otherwise it is undefined.

Attribute : weightIdentifier [0..1]: identifier
An optional weighting to be applied to the value of the variable. Weights are defined only in the test context (and hence only in outcomes processing) and only when the item identifier prefixing technique (see above) is being used to look up the value of an item variable. The weight identifier refers to a weight definition in the corresponding assessmentItemRef. If no matching definition is found the weight is assumed to be 1.0.

Weights only apply to item variables with base types integer and float. If the item variable is of any other type the weight is ignored. All weights are treated as having base type float and the resulting value is obtained by multiplying the variable's value by the associated weight. When applying a weight to the value of a variable with base type integer the value is subject to type promotion and the result of the expression has base type float.

Attribute : identifier [1]: identifier

This expression looks up the declaration of an itemVariable and returns the associated defaultValue or NULL if no default value was declared. When used in outcomes processing item identifier prefixing (see variable) may be used to obtain the default value from an individual item.

Attribute : identifier [1]: identifier

This expression looks up the declaration of a response variable and returns the associated correctResponse or NULL if no correct value was declared. When used in outcomes processing item identifier prefixing (see variable) may be used to obtain the correct response from an individual item.

Attribute : identifier [1]: identifier

This expression looks up the value of a response variable and then transforms it using the associated mapping, which must have been declared. The result is a single float. If the response variable has single cardinality then the value returned is simply the mapped target value from the map. If the response variable has multiple or ordered cardinality then the value returned is the sum of the mapped target values. This expression cannot be applied to variables of record cardinality.

For example, if a mapping associates the identifiers {A,B,C,D} with the values {0,1,0.5,0} respectively then mapResponse will map the single value 'C' to the numeric value 0.5 and the set of values {C,B} to the value 1.5.

If a container contains multiple instances of the same value then that value is counted once only. To continue the example above {B,B,C} would still map to 1.5 and not 2.5.

Attribute : identifier [1]: identifier

This expression looks up the value of a response variable that must be of base-type point, and transforms it using the associated areaMapping. The transformation is similar to mapResponse except that the points are tested against each area in turn. When mapping containers each area can be mapped once only. For example, if the candidate identified two points that both fall in the same area then the mappedValue is still added to the calculated total just once.

null is a simple expression that returns the NULL value—the null value is treated as if it is of any desired baseType.

Selects a random integer from the specified range [min,max] satisfying min + step * n for some integer n. For example, with min=2, max=11 and step=3 the values {2,5,8,11} are possible.

Attribute : min [1]: integerOrTemplateRef = 0

Attribute : max [1]: integerOrTemplateRef

Attribute : step [0..1]: integerOrTemplateRef = 1

Selects a random float from the specified range [min,max].

Attribute : min [1]: floatOrTemplateRef = 0

Attribute : max [1]: floatOrTemplateRef

This class defines the concept of a sub-set of the items selected in an assessmentTest. The attributes define criteria that must be matched by all members of the sub-set. It is used to control a number of expressions in outcomeProcessing for returning information about the test as a whole, or arbitrary subsets of it.

Attribute : sectionIdentifier [0..1]: identifier
If specified, only variables from items in the assessmentSection with matching identifier are matched. Items in sub-sections are included in this definition.

Attribute : includeCategory [*]: identifier
If specified, only variables from items with a matching category are included.

Attribute : excludeCategory [*]: identifier
If specified, only variables from items with no matching category are included.

This expression, which can only be used in outcomes processing, simultaneously looks up the value of an itemVariable in a sub-set of the items referred to in a test. Only variables with single cardinality are considered, all NULL values are ignored. The result has cardinality multiple and base-type as specified below.

Attribute : variableIdentifier [1]: identifier
The identifier of the variable to look up in each item. If a test brings together items with different variable naming conventions variableMappings may be used to reduce the complexity of outcomes processing and allow a single testVariables expression to be used. Items with no matching variable are ignored.

Attribute : baseType [0..1]: baseType
If specified, matches only variables declared with this baseType. This also becomes the base-type of the result (subject to type promotion through weighting, as described below). If omitted, variables declared with base-type integer or float are matched. The base-type of the result is integer if all matching values have base-type integer, otherwise it is float and integer values are subject to type promotion.

Attribute : weightIdentifier [0..1]: identifier
If specified, the defined weight is applied to each variable as described in the definition of weightIdentifier for a single variable. The behavior of this attribute is only defined if baseType is float or omitted. When a weighting is specified the result of the expression always has base-type float.

This expression, which can only be used in outcomes processing, simultaneously looks up the normalMaximum value of an outcome variable in a sub-set of the items referred to in a test. Only variables with single cardinality are considered. If any of the items within the given subset have no declared maximum the result is NULL, otherwise the result has cardinality multiple and base-type float.

Attribute : outcomeIdentifier [1]: identifier
As per the variableIdentifier attribute of testVariables.

Attribute : weightIdentifier [0..1]: identifier
As per the weightIdentifier attribute of testVariables.

This expression, which can only be used in outcomes processing, simultaneously looks up the normalMinimum value of an outcome variable in a sub-set of the items referred to in a test. Only variables with single cardinality are considered. Items with no declared minimum are ignored. The result has cardinality multiple and base-type float.

Attribute : outcomeIdentifier [1]: identifier
As per the variableIdentifier attribute of testVariables.

Attribute : weightIdentifier [0..1]: identifier
As per the weightIdentifier attribute of testVariables.

This expression, which can only be used in outcomes processing, calculates the number of items in a given sub-set, for which the all defined response variables match their associated correctResponse. Only items for which all declared response variables have correct responses defined are considered. The result is an integer with single cardinality.

This expression, which can only be used in outcomes processing, calculates the number of items in a given sub-set, for which at least one of the defined response variables does not match its associated correctResponse. Only items for which all declared response variables have correct responses defined and have been attempted at least once are considered. The result is an integer with single cardinality.

This expression, which can only be used in outcomes processing, calculates the number of items in a given sub-set that have been attempted (at least once) and for which a response was given. In other words, items for which at least one declared response has a value that differs from its declared default (typically NULL). The result is an integer with single cardinality.

This expression, which can only be used in outcomes processing, calculates the number of items in a given sub-set that have been attempted (at least once). In other words, items with which the user has interacted, whether or not they provided a response. The result is an integer with single cardinality.

This expression, which can only be used in outcomes processing, calculates the number of items in a given sub-set that have been selected for presentation to the candidate, regardless of whether the candidate has attempted them or not. The result is an integer with single cardinality.

Contains : expression [*]

The multiple operator takes 0 or more sub-expressions all of which must have either single or multiple cardinality. Although the sub-expressions may be of any base-type they must all be of the same base-type. The result is a container with multiple cardinality containing the values of the sub-expressions, sub-expressions with multiple cardinality have their individual values added to the result: containers cannot contain other containers. For example, when applied to A, B and {C,D} the multiple operator results in {A,B,C,D}. All sub-expressions with NULL values are ignored. If no sub-expressions are given (or all are NULL) then the result is NULL.

Contains : expression [*]

The ordered operator takes 0 or more sub-expressions all of which must have either single or ordered cardinality. Although the sub-expressions may be of any base-type they must all be of the same base-type. The result is a container with ordered cardinality containing the values of the sub-expressions, sub-expressions with ordered cardinality have their individual values added (in order) to the result: contains cannot contain other containers. For example, when applied to A, B, {C,D} the ordered operator results in {A,B,C,D}. Note that the ordered operator never results in an empty container. All sub-expressions with NULL values are ignored. If no sub-expressions are given (or all are NULL) then the result is NULL

Contains : expression [1]

The containerSize operator takes a sub-expression with any base-type and either multiple or ordered cardinality. The result is an integer giving the number of values in the sub-expression, in other words, the size of the container. If the sub-expression is NULL the result is 0. This operator can be used for determining how many choices were selected in a multiple-response choiceInteraction, for example.

Contains : expression [1]

The isNull operator takes a sub-expression with any base-type and cardinality. The result is a single boolean with a value of true if the sub-expression is NULL and false otherwise. Note that empty containers and empty strings are both treated as NULL.

Attribute : n [1]: integer

Contains : expression [1]

The index operator takes a sub-expression with an ordered container value and any base-type. The result is the n^th value of the container. The result has the same base-type as the sub-expression but single cardinality. The first value of a container has index 1, the second 2 and so on. n must be a positive integer. If n exceeds the number of values in the container then the result of the index operator is NULL.

Attribute : fieldIdentifier [1]: identifier
The identifier of the field to be selected.

Contains : expression [1]

The field-value operator takes a sub-expression with a record container value. The result is the value of the field with the specified fieldIdentifier. If there is no field with that identifier then the result of the operator is NULL.

Contains : expression [1]

The random operator takes a sub-expression with a multiple or ordered container value and any base-type. The result is a single value randomly selected from the container. The result has the same base-type as the sub-expression but single cardinality. If the sub-expression is NULL then the result is also NULL.

Contains : expression [2]

The member operator takes two sub-expressions which must both have the same base-type. The first sub-expression must have single cardinality and the second must be a multiple or ordered container. The result is a single boolean with a value of true if the value given by the first sub-expression is in the container defined by the second sub-expression. If either sub-expression is NULL then the result of the operator is NULL.

The member operator should not be used on sub-expressions with a base-type of float because of the poorly defined comparison of values. It must not be used on sub-expressions with a base-type of duration.

Contains : expression [2]

The delete operator takes two sub-expressions which must both have the same base-type. The first sub-expression must have single cardinality and the second must be a multiple or ordered container. The result is a new container derived from the second sub-expression with all instances of the first sub-expression removed. For example, when applied to A and {B,A,C,A} the result is the container {B,C}. If either sub-expression is NULL the result of the operator is NULL.

The restrictions that apply to the member operator also apply to the delete operator.

Contains : expression [2]

The contains operator takes two sub-expressions which must both have the same base-type and cardinality—either multiple or ordered. The result is a single boolean with a value of true if the container given by the first sub-expression contains the value given by the second sub-expression and false if it doesn't. Note that the contains operator works differently depending on the cardinality of the two sub-expressions. For unordered containers the values are compared without regard for ordering, for example, [A,B,C] contains [C,A]. Note that [A,B,C] does not contain [B,B] but that [A,B,B,C] does. For ordered containers the second sub-expression must be a strict sub-sequence within the first. In other words, [A,B,C] does not contain [C,A] but it does contain [B,C].

If either sub-expression is NULL then the result of the operator is NULL. Like the member operator, the contains operator should not be used on sub-expressions with a base-type of float and must not be used on sub-expressions with a base-type of duration.

Contains : expression [2]

The substring operator takes two sub-expressions which must both have an effective base-type of string and single cardinality. The result is a single boolean with a value of true if the first expression is a substring of the second expression and false if it isn't. If either sub-expression is NULL then the result of the operator is NULL.

Attribute : caseSensitive [1]: boolean = true
Used to control whether or not the substring is matched case sensitively. If true then the match is case sensitive and, for example, "Hell" is not a substring of "Shell". If false then the match is not case sensitive and "Hell" is a substring of "Shell".

Contains : expression [1]

The not operator takes a single sub-expression with a base-type of boolean and single cardinality. The result is a single boolean with a value obtained by the logical negation of the sub-expression's value. If the sub-expression is NULL then the not operator also results in NULL.

Contains : expression [1..*]

The and operator takes one or more sub-expressions each with a base-type of boolean and single cardinality. The result is a single boolean which is true if all sub-expressions are true and false if any of them are false. If one or more sub-expressions are NULL and all others are true then the operator also results in NULL.

Contains : expression [1..*]

The or operator takes one or more sub-expressions each with a base-type of boolean and single cardinality. The result is a single boolean which is true if any of the sub-expressions are true and false if all of them are false. If one or more sub-expressions are NULL and all the others are false then the operator also results in NULL.

Contains : expression [1..*]

The anyN operator takes one or more sub-expressions each with a base-type of boolean and single cardinality. The result is a single boolean which is true if at least min of the sub-expressions are true and at most max of the sub-expressions are true. If more than n - min sub-expressions are false (where n is the total number of sub-expressions) or more than max sub-expressions are true then the result is false. If one or more sub-expressions are NULL then it is possible that neither of these conditions is satisfied, in which case the operator results in NULL. For example, if min is 3 and max is 4 and the sub-expressions have values {true,true,false,NULL} then the operator results in NULL whereas {true,false,false,NULL} results in false and {true,true,true,NULL} results in true. The result NULL indicates that the correct value for the operator cannot be determined.

Attribute : min [1]: integerOrTemplateRef
The minimum number of sub-expressions that must be true.

Attribute : max [1]: integerOrTemplateRef
The maximum number of sub-expressions that may be true.

Contains : expression [2]

The match operator takes two sub-expressions which must both have the same base-type and cardinality. The result is a single boolean with a value of true if the two expressions represent the same value and false if they do not. If either sub-expression is NULL then the operator results in NULL.

The match operator must not be confused with broader notions of equality such as numerical equality. To avoid confusion, the match operator should not be used to compare subexpressions with base-types of float and must not be used on sub-expressions with a base-type of duration.

Contains : expression [2]

The stringMatch operator takes two sub-expressions which must have single and a base-type of string. The result is a single boolean with a value of true if the two strings match according to the comparison rules defined by the attributes below and false if they don't. If either sub-expression is NULL then the operator results in NULL.

Attribute : caseSensitive [1]: boolean
Whether or not the match is to be carried out case sensitively.

Attribute : substring [0..1]: boolean = false
This attribute is now deprecated, the substring operator should be used instead. If true, then the comparison returns true if the first string contains the second one, otherwise it returns true only if they match entirely.

Contains : expression [1]

The patternMatch operator takes a sub-expression which must have single cardinality and a base-type of string. The result is a single boolean with a value of true if the sub-expression matches the regular expression given by pattern and false if it doesn't. If the sub-expression is NULL then the operator results in NULL.

Attribute : pattern [1]: stringOrTemplateRef
The syntax for the regular expression language is as defined in Appendix F of [XML_SCHEMA2].

Contains : expression [2]

The equal operator takes two sub-expressions which must both have single cardinality and have a numerical base-type. The result is a single boolean with a value of true if the two expressions are numerically equal and false if they are not. If either sub-expression is NULL then the operator results in NULL.

Attribute : toleranceMode [1]: toleranceMode = exact
When comparing two floating point numbers for equality it is often desirable to have a tolerance to ensure that spurious errors in scoring are not introduced by rounding errors. The tolerance mode determines whether the comparison is done exactly, using an absolute range or a relative range.

Attribute : tolerance [0..2]: floatOrTemplateRef
If the tolerance mode is absolute or relative then the tolerance must be specified. The tolerance consists of two positive numbers, t0 and t1, that define the lower and upper bounds. If only one value is given it is used for both.

In absolute mode the result of the comparison is true if the value of the second expression, y is within the following range defined by the first value, x.

x-t0,x+t1

In relative mode, t0 and t1 are treated as percentages and the following range is used instead.

x*(1-t0/100),x*(1+t1/100)

Attribute : includeLowerBound [0..1]: boolean = true
Controls whether or not the lower bound is included in the comparison

Attribute : includeUpperBound [0..1]: boolean = true
Controls whether or not the upper bound is included in the comparison

exact

absolute

relative

Contains : expression [2]

The equalRounded operator takes two sub-expressions which must both have single cardinality and have a numerical base-type. The result is a single boolean with a value of true if the two expressions are numerically equal after rounding and false if they are not. If either sub-expression is NULL then the operator results in NULL.

Attribute : roundingMode [1]: roundingMode = significantFigures
Numbers are rounded to a given number of significantFigures or decimalPlaces.

Attribute : figures [1]: integerOrTemplateRef
The number of figures to round to.

For example, if the two values are 1.56 and 1.6 and significantFigures mode is used with figures=2 then the result would be true.

significantFigures

decimalPlaces

Contains : expression [1]

The inside operator takes a single sub-expression which must have a baseType of point. The result is a single boolean with a value of true if the given point is inside the area defined by shape and coords. If the sub-expression is a container the result is true if any of the points are inside the area. If either sub-expression is NULL then the operator results in NULL.

Attribute : shape [1]: shape
The shape of the area.

Attribute : coords [1]: coords
The size and position of the area, interpreted in conjunction with the shape.

Contains : expression [2]

The lt operator takes two sub-expressions which must both have single cardinality and have a numerical base-type. The result is a single boolean with a value of true if the first expression is numerically less than the second and false if it is greater than or equal to the second. If either sub-expression is NULL then the operator results in NULL.

Contains : expression [2]

The gt operator takes two sub-expressions which must both have single cardinality and have a numerical base-type. The result is a single boolean with a value of true if the first expression is numerically greater than the second and false if it is less than or equal to the second. If either sub-expression is NULL then the operator results in NULL.

Contains : expression [2]

The lte operator takes two sub-expressions which must both have single cardinality and have a numerical base-type. The result is a single boolean with a value of true if the first expression is numerically less than or equal to the second and false if it is greater than the second. If either sub-expression is NULL then the operator results in NULL.

Contains : expression [2]

The gte operator takes two sub-expressions which must both have single cardinality and have a numerical base-type. The result is a single boolean with a value of true if the first expression is numerically less than or equal to the second and false if it is greater than the second. If either sub-expression is NULL then the operator results in NULL.

Contains : expression [2]

The durationLT operator takes two sub-expressions which must both have single cardinality and base-type duration. The result is a single boolean with a value of true if the first duration is shorter than the second and false if it is longer than (or equal) to the second. If either sub-expression is NULL then the operator results in NULL.

There is no 'durationLTE' or 'durationGT' because equality of duration is meaningless given the variable precision allowed by duration. Given that duration values are obtained by truncation rather than rounding it makes sense to test only less-than or greater-than-equal inequalities only. For example, if we want to determine if a candidate took less than 10 seconds to complete a task in a system that reports durations to a resolution of epsilon seconds (epsilon<1) then a value equal to 10 would cover all durations in the range [10,10+epsilon).

Contains : expression [2]

The durationGTE operator takes two sub-expressions which must both have single cardinality and base-type duration. The result is a single boolean with a value of true if the first duration is longer (or equal, within the limits imposed by truncation as described above) than the second and false if it is shorter than the second. If either sub-expression is NULL then the operator results in NULL.

See durationLT for more information about testing the equality of durations.

Contains : expression [1..*]

The sum operator takes 1 or more sub-expressions which all have single cardinality and have numerical base-types. The result is a single float or, if all sub-expressions are of integer type, a single integer that corresponds to the sum of the numerical values of the sub-expressions. If any of the sub-expressions are NULL then the operator results in NULL.

Contains : expression [1..*]

The product operator takes 1 or more sub-expressions which all have single cardinality and have numerical base-types. The result is a single float or, if all sub-expressions are of integer type, a single integer that corresponds to the product of the numerical values of the sub-expressions. If any of the sub-expressions are NULL then the operator results in NULL.

Contains : expression [2]

The subtract operator takes 2 sub-expressions which all have single cardinality and numerical base-types. The result is a single float or, if both sub-expressions are of integer type, a single integer that corresponds to the first value minus the second. If either of the sub-expressions is NULL then the operator results in NULL.

Contains : expression [2]

The divide operator takes 2 sub-expressions which both have single cardinality and numerical base-types. The result is a single float that corresponds to the first expression divided by the second expression. If either of the sub-expressions is NULL then the operator results in NULL.

Item authors should make every effort to ensure that the value of the second expression is never 0, however, if it is zero or the resulting value is outside the value set defined by float (not including positive and negative infinity) then the operator should result in NULL.

Contains : expression [2]

The power operator takes 2 sub-expression which both have single cardinality and numerical base-types. The result is a single float that corresponds to the first expression raised to the power of the second. If either or the sub-expressions is NULL then the operator results in NULL.

If the resulting value is outside the value set defined by float (not including positive and negative infinity) then the operator shall result in NULL.

Contains : expression [2]

The integer divide operator takes 2 sub-expressions which both have single cardinality and base-type integer. The result is the single integer that corresponds to the first expression (x) divided by the second expression (y) rounded down to the greatest integer (i) such that i<=(x/y). If y is 0, or if either of the sub-expressions is NULL then the operator results in NULL.

Contains : expression [2]

The integer modulus operator takes 2 sub-expressions which both have single cardinality and base-type integer. The result is the single integer that corresponds to the remainder when the first expression (x) is divided by the second expression (y). If z is the result of the corresponding integerDivide operator then the result is x-z*y. If y is 0, or if either of the sub-expressions is NULL then the operator results in NULL.

Contains : expression [1]

The truncate operator takes a single sub-expression which must have single cardinality and base-type float. The result is a value of base-type integer formed by truncating the value of the sub-expression towards zero. For example, the value 6.8 becomes 6 and the value -6.8 becomes -6. If the sub-expression is NULL then the operator results in NULL.

Contains : expression [1]

The round operator takes a single sub-expression which must have single cardinality and base-type float. The result is a value of base-type integer formed by rounding the value of the sub-expression. The result is the integer n for all input values in the range [n-0.5,n+0.5). In other words, 6.8 and 6.5 both round up to 7, 6.49 rounds down to 6 and -6.5 rounds up to -6. If the sub-expression is NULL then the operator results in NULL.

Contains : expression [1]

The integer to float conversion operator takes a single sub-expression which must have single cardinality and base-type integer. The result is a value of base type float with the same numeric value. If the sub-expression is NULL then the operator results in NULL.

The custom operator provides an extension mechanism for defining operations not currently supported by this specification.

Attribute : class [0..1]: identifier
The class attribute allows simple sub-classes to be named. The definition of a sub-class is tool specific and may be inferred from toolName and toolVersion.

Attribute : definition [0..1]: uri
A URI that identifies the definition of the custom operator in the global namespace.

In addition to the class and definition attributes, sub-classes may add any number of attributes of their own.

Contains : expression [*]
Custom operators can take any number of sub-expressions of any type to be treated as parameters.

It has been suggested that customOperator might be used to help link processing rules defined by this specification to instances of web-service based processing engines. For example, a web-service which offered automated marking of free text responses. Implementors experimenting with this approach are encouraged to share information about their solutions to help determine the best way to achieve this type of processing.

Fragments are included using the Xinclude mechanism. (See [XINCLUDE].) The instance of include is treated as if it was actually an instance of the root element of the fragment referred to by the href attribute of the include element. For the purposes of this specification the xpointer mechanism defined by the XInclude specification must not be used. Also, all included fragments must be treated as parsed xml.

Contains : responseRule [*]

A responseProcessingFragment is a simple group of responseRules which are grouped together in order to allow them to be managed as a separate resource. It should not be used for any other purpose.

Note that a response processing template allows a system to carry out response processing without having to parse the individual response processing rules. On the other hand, a responseProcessing element containing a reference to a an externally defined response processing fragment must be parsed to determine the actions to carry out.

Contains : outcomeRule [*]

An outcomeProcessingFragment is a simple group of outcomeRules which are grouped together in order to allow them to be managed as a separate resource. It should not be used for any other purpose.

A boolean value is either true or false. Note that lexical bindings to strings such as "Yes", "TRUE", "1", etc. are outside the scope of this document.

The coords type provides the coordinates that determine the size and location of an area defined by a corresponding shape.

The coordinates themselves are an ordered list of lengths (as defined in [XHTML]). The interpretation of each length value is dependent on the value of the associated shape as follows.

• rect: left-x, top-y, right-x, bottom-y.
• circle: center-x, center-y, radius. Note. When the radius value is a percentage value, user agents should calculate the final radius value based on the associated object's width and height. The radius should be the smaller value of the two.
• poly: x1, y1, x2, y2, ..., xN, yN. The first x and y coordinate pair and the last should be the same to close the polygon. When these coordinate values are not the same, user agents should infer an additional coordinate pair to close the polygon.
• ellipse: center-x, center-y, h-radius, v-radius. Note that the ellipse shape is deprecated as it is not defined by [XHTML].
• default: no coordinates should be given.

A fully-specified calendar date, including year, month and day of month from the reference system defined in [ISO8601]. Valid years range from 0001-9999. Year values have no timezone information.

A fully-specified calendar date and time from the reference system defined in [ISO8601]. Valid years range from 0000-9999.

A period of time, measured in seconds.

The IEEE double-precision 64-bit floating point type.

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 future use. The character classes Letter, Digit, CombiningChar and Extender are defined in the Extensible Markup Language (XML) 1.0 (Second Edition) [XML]. 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.

An integer value is a whole number in the range [-2147483648,2147483647]. This is the range of a twos-complement 32-bit integer.

Natural language identifiers as defined by [RFC3066].

The length datatype is as defined in [XHTML].

The set of mime types (type and subtype), as defined by [RFC2045].

vertical

horizontal

A value of a shape is alway accompanied by coordinates (see coords and an associated image which provides a context for interpreting them.

default
The default shape refers to the entire area of the associated image.

rect
A rectangular region.

circle
A circular region

poly
An arbitrary polygonal region

ellipse
This value is deprecated, but is included for compatibility with version of 1 of the QTI specification. Systems should use circle or poly shapes instead.

A string value is any sequence of characters. A character is anything in the class Char defined in Extensible Markup Language (XML) 1.0 (Second Edition).

A string value (as per string) that is limited to 256 characters in length.

The type used when referring to a class definition, for example in a stylesheet. Class names cannot contain spaces.

A Uniform Resource Identifier as defined in [URI].

A simple type used to represent a single value of any baseType as defined by the assessment variable data model.

author

candidate

proctor
Sometimes referred to as an invigilator

scorer

testConstructor

tutor