Computerized Adaptive Testing

Adaption of the item difficulty level to the subject's characteristics is the most efficient method in characteristics testing. To achieve this goal, a number of items were presented to the subjects to gain an exact understanding of their levels. The above mentioned issue comprises the fundamental idea underlying the adaptive testing which is influenced by the outcomes of the item-response theory in the analysis of a test questions. Adaptive testing is the natural result of Bayesian thinking method in estimating and analyzing the information function of the items and includes some inferences for the preparation and interpretation of the test. This method includes a number of simple and yet various approximations. A more complex method of adaptive testing is the Computerized Adaptive Testing (CAT), which includes a two stage process. In the first stage, an item will be presented to the subjects with the same difficulty level as their current abilities. Then, their abilities will be measured on the basis of their responses to the item of the first stage. These stages are repeated over and over to make the ultimate decision to end the test. Real planning, practical application, and CAT protection demand hard work including: item pools, test security, and examinee issues.