TY - JOUR T1 - Methods for restricting maximum exposure rate in computerized adaptative testing JF - Methodology: European Journal of Research Methods for the Behavioral and Social Sciences Y1 - 2007 A1 - Barrada, J A1 - Olea, J. A1 - Ponsoda, V. KW - computerized adaptive testing KW - item bank security KW - item exposure control KW - overlap rate KW - Sympson-Hetter method AB - The Sympson-Hetter (1985) method provides a means of controlling maximum exposure rate of items in Computerized Adaptive Testing. Through a series of simulations, control parameters are set that mark the probability of administration of an item on being selected. This method presents two main problems: it requires a long computation time for calculating the parameters and the maximum exposure rate is slightly above the fixed limit. Van der Linden (2003) presented two alternatives which appear to solve both of the problems. The impact of these methods in the measurement accuracy has not been tested yet. We show how these methods over-restrict the exposure of some highly discriminating items and, thus, the accuracy is decreased. It also shown that, when the desired maximum exposure rate is near the minimum possible value, these methods offer an empirical maximum exposure rate clearly above the goal. A new method, based on the initial estimation of the probability of administration and the probability of selection of the items with the restricted method (Revuelta & Ponsoda, 1998), is presented in this paper. It can be used with the Sympson-Hetter method and with the two van der Linden's methods. This option, when used with Sympson-Hetter, speeds the convergence of the control parameters without decreasing the accuracy. (PsycINFO Database Record (c) 2007 APA, all rights reserved) PB - Hogrefe & Huber Publishers GmbH: Germany VL - 3 SN - 1614-1881 (Print); 1614-2241 (Electronic) ER -