A key consideration when giving any computerized adaptive test (CAT) is how much adaptation is present when the test is used in practice. This study introduces a new framework to measure the amount of adaptation of Rasch-based CATs based on looking at the differences between the selected item locations (Rasch item difficulty parameters) of the…

A common practical challenge is how to assign ability estimates to all incorrect and all correct response patterns when using item response theory (IRT) models and maximum likelihood estimation (MLE) since ability estimates for these types of responses equal -8 or +8. This article uses a simulation study and data from an operational K-12…

Technical adequacy and information/cost return were examined for four early reading measures: the Dynamic Indicators of Basic Early Literacy Skills (DIBELS), STAR Early Literacy (SEL), Group Reading Assessment and Diagnostic Evaluation (GRADE), and the Texas Primary Reading Inventory (TPRI). All four assessments were administered to the same…

Describes a system in which questions tailored to the examinee's capabilities are administered by computer. Enumerates possible benefits of the system, reviews the "state of the art," and predicts potential applications of computerized adaptive testing. (MCG)

Computer simulation was used to assess the effects of item parameter estimation errors on different item selection strategies used in adaptive and conventional testing. To determine whether these effects reduced the advantages of certain optimal item selection strategies, simulations were repeated in the presence and absence of item parameter…

A series of four vocabulary norming tests was used to develop a large, homogeneous pool of vocabulary test items for use in computer-administered adaptive testing research. Five hundred seventy-five unique vocabulary knowledge items were divided among the four norming tests, and administered to separate groups of college undergraduates. Norming…

Four monte carlo simulation studies of Owen's Bayesian sequential procedure for adaptive mental testing were conducted. Whereas previous simulation studies of this procedure have concentrated on evaluating it in terms of the correlation of its test scores with simulated ability in a normal population, these four studies explored a number of…

A pilot study of a computerized adaptive test of mathematics achievement was conducted in May and June 1989 in selected schools of the San Diego Unified School District. The study evaluated the usefulness of the test for determining eligibility for Chapter 1 programs in mathematics. The test was a prototype battery of three adaptive tests: (1)…

The Computerized Adaptive Testing (CAT) project is a joint Armed Services coordinated effort to develop and evaluate a system for automated, adaptive administration of the Armed Services Vocational Aptitude Battery (ASVAB). The CAT is a system for administering personnel tests that differs from conventional test administration in two major…

In an adaptive test, the test administrator chooses test items sequentially during the test, in such a way as to adapt test difficulty to examinee ability as shown during testing. An effectively designed adaptive test can resolve the dilemma inherent in conventional test design. By tailoring tests to individuals, the adaptive test can…

The results of a series of simulation studies designed to investigate the influence of guessing and item pool characteristics on the bias, accuracy, and information properties of the trait estimates derived from Owen's Bayesian sequential testing strategy are reported. (RC)

Monte Carlo simulation was used to investigate score bias and information characteristics of Owen's Bayesian adaptive testing strategy, and to examine possible causes of score bias. Factors investigated in three related studies included effects of item discrimination, effects of fixed vs. variable test length, and effects of an accurate prior…

The advantages of computerized adaptive testing are discussed, and an example illustrates its use in sixth grade mathematics. These tests are administered at a computer terminal, and the test items to be administered are selected according to the difficulty level appropriate to the individual's ability. Tailoring increases the psychometric…

An overview of the development of a computerized version of the Differential Aptitude Tests (DAT) is presented. It describes the previously existing printed version of the DAT, design of the computerized adaptive edition, calibration of the test items for use in the computerized version, and two field studies that compared the Adaptive and…