ERIC Number: ED419004
Record Type: RIE
Publication Date: 1997
Reference Count: N/A
A Procedure for Empirical Initialization of Adaptive Testing Algorithms.
van der Linden, Wim J.
In constrained adaptive testing, the numbers of constraints needed to control the content of the tests can easily run into the hundreds. Proper initialization of the algorithm becomes a requirement because the presence of large numbers of constraints slows down the convergence of the ability estimator. In this paper, an empirical initialization of the algorithm is proposed based on the statistical relation between the ability variable and background variables known prior to the test. The relation is modeled using a two-parameter logistic version of an item response theory (IRT) model with manifest predictors discussed in A. H. Zwinderman (1991). An empirical example shows how an (incomplete) sample of response data and data on background variables can be used to derive an initial ability estimate or an empirical prior distribution for the ability parameter. An appendix gives the derivation of an equation for the estimator. (Contains 12 references.) (Author/SLD)
Descriptors: Ability, Adaptive Testing, Algorithms, Computer Assisted Testing, Foreign Countries, Item Response Theory, Test Construction
Faculty of Educational Science and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands.
Publication Type: Reports - Evaluative
Education Level: N/A
Authoring Institution: Twente Univ., Enschede (Netherlands). Faculty of Educational Science and Technology.
Identifiers: Constraints; Two Parameter Model