Academic Testing Item Response Theory Approach

CTT is best suited for traditional testing situations, either in group or individual settings, in which all the members of a target population, e.g., persons seeking college admission, are administered the same or parallel sets of test items. These item sets can be presented to the examinee in either a paper-and-pencil or a computer format. Regardless of format, it is important for the measurement of individual ability that the items in each item set have "difficulties" that match the range of ability or proficiency in the population. In addition, precise estimation of individual ability requires the administration of a "large enough" number of items whose difficulty levels narrowly match the individual's level of ability or proficiency. For heterogeneous populations these requirements of the "fixed length" test result in inefficient and wasteful testing situations that are certainly frustrating to the examinee.