Task model. A task is simply something specific that test
developers ask a test taker to do that will be scored, such as select an
option in a multiple choice item, write an essay, or take the required
action in response to a performance item. A task model is a
description of the characteristics that define a group of tasks. The
task model should, of course, be linked to the aspect(s) of the
evidence model for which it will provide information.
Task models can help test developers design or select appropriate
types of tasks to use for a test. The task model requires the test
developer to describe the desired attributes of the tasks to be
generated. The task model helps test developers determine the
various item types that can display the desired attributes before the
test developers commit to a particular item type.
The task model describes a family of tasks. It defines a group of
situations that would elicit the desired observable behavior or
observable product. A task model generally includes 1) a description
of the KSAs that the tasks measure; 2) the types of stimulus
materials that might be used; 3) a description of what the test taker
will be asked to do; 4) descriptions of required task elements and
allowable variable task elements; 5) the attributes that affect the
difficulties of the tasks that will eventually be produced; and 6)
several samples of tasks that could be generated by the model. The
sample tasks are very important in helping test developers
understand the model.