Estimating an Examinee’s Ability

Abstract

Under item response theory , the primary purpose for administering a test to an examinee is to locate that person on the ability scale. If such an ability measure can be obtained for each person taking the test, two goals can be achieved. First, the examinee can be evaluated in terms of how much underlying ability he or she possesses. Second, comparisons among examinees can be made for purposes of assigning grades, awarding scholarships, etc. Thus, the focus of this chapter is upon the examinees and the procedures for estimating an ability score (parameter) for an examinee.