Suggests that because of the nonlinear relationship between item usage and item security, the problems of test security posed by continuous administration of standardized tests cannot be resolved merely by increasing the size of the item pool. Offers alternative strategies to overcome these problems, distributing test items so as to avoid the…

The pure Rasch model was compared with four modifications of the model in a number of different simulations in order to ascertain the comparative efficiencies of the parameter estimations of these modifications. Because there is always noise in test score data, some individuals may have response patterns that do not fit the model and their…

A mathematics item on the Scholastic Aptitude Test (SAT) was found to be faulty and received wide publicity. A detailed investigation into its mathematical and psychometric properties is presented. It was found that the problem could be considered ambiguous but that almost no one noticed the ambiguity. (Author/JKS)

The testlet, a bundle of test items, alleviates some problems associated with computerized adaptive testing: context effects, lack of robustness, and item difficulty ordering. While testlets may be linear or hierarchical, the most useful ones are four-level hierarchical units, containing 15 items and partitioning examinees into 16 classes. (GDC)

The comparability of scores on test forms that are constructed through examinee item choice is examined in an item response theory framework. The approach is illustrated with data from the College Board's Advanced Placement Test in Chemistry taken by over 18,000 examinees. (SLD)

Some cautions are sounded for converting a linearly administered test to an adaptive format. Four areas are identified in which practices broadly used in traditionally constructed tests can have adverse effects if thoughtlessly adopted when a test is administered in an adaptive mode. (SLD)

Three different applications of the testlet concept are presented, and the psychometric models most suitable for each application are described. Difficulties that testlets can help overcome include (1) context effects; (2) item ordering; and (3) content balancing. Implications for test construction are discussed. (SLD)

Two attempts to adjust state mean Scholastic Aptitude Test (SAT) scores for differential participation rates are examined. Both attempts are rejected, and five rules for performing adjustments are outlined to foster follow-up checks on untested assumptions. National Assessment of Educational Progress state data are determined to be more accurate.…

Describes recent research attempts to draw inferences about the relative standing of the states on the basis of mean SAT scores. This paper identifies five serious errors that call into question the validity of such inferences. Some plausible ways to avoid the errors are described. (Author/LMO)

It is important to estimate the number of examinees who reached a test item, because item difficulty is defined by the number who answered correctly divided by the number who reached the item. A new method is presented and compared to the previously used definition of three categories of response to an item: (1) answered; (2) omitted--a…

Recent experience with the Computerized Adaptive Test (CAT) has raised a number of concerns about its practical applications. The concerns are principally involved with the concept of having the computer construct the test from a precalibrated item pool, and substituting statistical characteristics for the test developer's skills. Problems with…