ERIC Number: ED473533
Record Type: Non-Journal
Publication Date: 2002
Reference Count: N/A
Constructing Rotating Item Pools for Constrained Adaptive Testing. Research Report.
Ariel, Adelaide; Veldkamp, Bernard P.; van der Linden, Wim J.
Preventing items in adaptive testing from being over- or underexposed is one of the main problems in computerized adaptive testing. Though the problem of overexposed items can be solved using a probabilistic item-exposure control method, such methods are unable to deal with the problem of underexposed items. Using a system of rotating item pools, on the other hand, is a method that potentially solves both problems. In this method, a master pool is divided into (possibly overlapping) smaller item pools that are required to have similar distributions of content and statistical attributes. These pools are rotated among the testing sites to realize desirable exposure rates for the items. In this paper, a test assembly model for the problem of dividing a master pool into a set of smaller pools is presented. The model was motivated by Gullicksen's (1950) matched random subtests method. Different methods to solve the model are proposed. An item pool from the Law School Admission Test was used to evaluate the performances of computerized adaptive tests from systems of rotating item pools constructed using these methods. (Contains 6 figures and 14 references.) (Author/SLD)
Faculty of Educational Science and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands. E-mail: Fox@edte.utwente.nl.
Publication Type: Reports - Research
Education Level: N/A
Authoring Institution: Twente Univ., Enschede (Netherlands). Faculty of Educational Science and Technology.