This chapter introduces theory that undergirds the role of testing adaptations in assessment, provides examples of item modifications and testing accommodations, reviews research relevant to each, and introduces a new paradigm that incorporates opportunity to learn (OTL), academic enablers, testing adaptations, and inferences that can be made from…

An adaptive testing method is presented that controls the speededness of a test using predictions of the test takers' response times on the candidate items in the pool. Two different types of predictions are investigated: posterior predictions given the actual response times on the items already administered and posterior predictions that use the…

A potential undesirable effect of multistage testing is differential speededness, which happens if some of the test takers run out of time because they receive subtests with items that are more time intensive than others. This article shows how a probabilistic response-time model can be used for estimating differences in time intensities and speed…

The reliability coefficient is predicted from the test information function (TIF) or two modified TIF formulas and a specific trait distribution. Examples illustrate the variability of the reliability coefficient across different trait distributions, and results are compared with empirical reliability coefficients. (SLD)

The designing of tests has been a source of concern for test developers over the past decade. Various kinds of test forms have been applied. Among these are the fixed-form test, the adaptive test, and the testlet. Each of these forms has its own design. In this paper, the construction of test forms is placed within the general framework of optimal…

Two local methods for observed-score equating are applied to the problem of equating an adaptive test to a linear test. In an empirical study, the methods were evaluated against a method based on the test characteristic function (TCF) of the linear test and traditional equipercentile equating applied to the ability estimates on the adaptive test…

Four researchers at the Educational Testing Service describe what they consider some of the most vexing research problems they face. While these problems are not completely statistical, they all have major statistical components. Following the introduction (section 1), in section 2, "Problems with the Simultaneous Estimation of Many True…

Concepts of adaptive testing and the related measurement model, item response theory, are introduced and benefits and limitations are outlined. Field tests with over 2,500 students illustrate the use of adaptive tests in college placement. Some future directions for computerized adaptive testing are considered. (SLD)