Computerized Adaptive Testing

A method of item pool design is proposed that uses an optimal blueprint for the item pool calculated from the test specifications. The blueprint is a document that specifies the attributes that the items in the computerized adaptive test (CAT) pool should have. The blueprint can be a starting point for the item writing process, and it can be used to assemble item pools in a system of rotating pools from a master pool. The blueprint is also useful for item pool maintenance. Designing the blueprint begins with analyzing the specifications for the CAT, a step amounting to the formation of a classification table involving categorization of quantitative item attributes. Using this table, an integer programming model for the assembly of the shadow tests in the CAT simulation is constructed. An estimate of the ability distribution of the identified population of examinees is obtained, and the CAT simulation is carried out using the integer programming model for the shadow tests and sampling simulees from the ability distribution. The blueprint is then calculated from the counts of the number of items from the cells in the classification table. The best way to implement the blueprint is in a sequential fashion recalculating the blueprint after a certain portion of the items has actually been written and tested so that their attribute values are known. (Contains 16 references and a list of University of Twente research reports.) (SLD) ******************************************************************************** Reproductions supplied by EDRS are the best that can be made from the original document. ******************************************************************************** 0 g Designing Item Pools for F. Az I Computerized Adaptive Testing Bernard P. Veldkamp Wim J. van der Linden facui EDU AND' PERMISSION TO REPRODUCE AND DISSEMINATE THIS MATERIAL HAS BEEN GRANTED BY N eli TO THE EDUCATIONAL RESOURCES INFORMATION CENTER (ERIC) of ATIONAL SCIENCE TECHNOLOGY Department of Educational M asurement and J fta Analysis Research Report 99-03 U.S. DEPARTMENT OF EDUCATION Office of Educational Research and Improvement EDUCATIONAL RESOURCES INFORMATION CENTER (ERIC) Der.iic document has been reproduced as received from the person or organization originating it. Minor changes have been made to improve reproduction quality, Points of view or opinions stated in this document do not necessarily represent official OERI position or policy. University of Twente I 2 I BEST COPYAVAILA8LE Designing Item Pools for Computerized Adaptive Testing Bernard P. Veldkamp Wim J. van der Linden