A comparability approach to item reduction in Computerized Adaptive Testing

Computerized Adaptive Testing (CAT) is a widely used computer based testing that can classify examinees according to their abilities. The question sent to each examinee depends on his/her answers to previous questions. One drawback is that CAT is not suitable for a small examination pool since it may not guarantee to cover all topics. The purpose of this study is to introduce a new adaptive testing method called Comparable Item Reduction CAT which has many attractive features such as the ability to operate on an item pool whose size is fixed and to assure that all topics are distributed equally and efficiently. The result is the test that is shorter in length and accurate in each examineepsilas ability estimation.