%0 Journal Article
%T A Continuous a
%A Alan Huebner
%A Bridget Daly
%A Chun Wang
%A Colleen Pinkelman
%J Applied Psychological Measurement
%@ 1552-3497
%D 2018
%R 10.1177/0146621618758289
%X The method of a -stratification aims to reduce item overexposure in computerized adaptive testing, as items that are administered at very high rates may threaten the validity of test scores. In existing methods of a -stratification, the item bank is partitioned into a fixed number of nonoverlapping strata according to the itemsĄŻ a , or discrimination, parameters. This article introduces a continuous a -stratification index which incorporates exposure control into the item selection index itself and thus eliminates the need for fixed discrete strata. The new continuous a -stratification index is compared with existing stratification methods via simulation studies in terms of ability estimation bias, mean squared error, and control of item exposure rates
%K computerized adaptive testing
%K item exposure control
%K item response theory
%U https://journals.sagepub.com/doi/full/10.1177/0146621618758289