Abstract

Item response theory (IRT) lends itself perfectly to the application of optimal design principles to the problem of test assembly. The first to open our eyes to the opportunity was Birnbaum in his contributions on the three-parameter logistic (3PL) model to Lord and Novick (1968). His basic idea was to use the notion of the Fisher information on the test takers' ability parameters in the responses to the test items to optimize the selection of a test form from a calibrated item pool.