This article addresses the issue of how to detect item preknowledge using item response time data in two computer-based large-scale licensure examinations. Item preknowledge is indicated by an unexpected short response time and a correct response. Two samples were used for detecting item preknowledge for each examination. The first sample was from…

Some effects of using unidimensional item response theory (IRT) were examined when the assumption of unidimensionality was violated. Adaptive and nonadaptive tests were used. It appears that use of a unidimensional model can bias parameter estimation, adaptive item selection, and ability estimation for the two types of testing. (TJH)

The precision of a computerized adaptive test (CAT) with a limited item pool was measured using test results from 4,494 nursing students. Regardless of the item pool size, CAT provides greater precision in measurement with a smaller number of items administered even when the choice of items is limited, but CAT fails to achieve equiprecision along…

Computer Adaptive Sequential Testing (CAST) is a test delivery model that combines features of the traditional conventional paper-and-pencil testing and item-based computerized adaptive testing (CAT). The basic structure of CAST is a panel composed of multiple testlets adaptively administered to examinees at different stages. Current applications…

A method is proposed that increases the accuracies of estimation of the operating characteristics of discrete item responses, especially when the true operating characteristic is represented by a steep curve, and also at the lower and upper ends of the ability distribution where the estimation tends to be inaccurate because of the smaller number…

The effect of dimensionality on an adaptive test's ability estimation was examined. Two-dimensional data sets, which differed from one another in the interdimensional ability association, the correlation among the difficulty parameters, and whether the item discriminations were or were not confounded with item difficulty, were generated for 1,600…

F. M. Lord's flexilevel, computerized adaptive testing (CAT) procedure was compared to an item-response theory-based CAT procedure that uses Bayesian ability estimation with various standard errors of estimates used for terminating the test. Ability estimates of flexilevel CATs were as accurate as were those of Bayesian CATs. (TJH)

According to item response theory (IRT), examinee ability estimation is independent of the particular set of test items administered from a calibrated pool. Although the most popular application of this feature of IRT is computerized adaptive (CA) testing, a recently proposed alternative is self-adapted (SA) testing, in which examinees choose the…

Two modification formulas are presented for the test information function in order to provide better measures of local accuracies of the estimation of "theta" when maximum likelihood estimation is used to provide the estimate of ability "theta." A minimum bound of any estimator, biased or unbiased, is considered; and Formula 1…

This study explores the test-retest consistency of computer adaptive tests of varying lengths. The testing model used was designed as a mastery model to determine whether an examinee's estimated ability level is above or below a pre-established criterion expressed in the metric (logits) of the calibrated item pool scale. The Rasch model was used…