The purpose of this study was to examine the effects of answer copying on the ability level estimates of cheater examinees in answer copying pairs. The study generated answer copying pairs for each of 1440 conditions, source ability (12) x cheater ability (12) x amount of copying (10). The average difference between the ability level estimates…

An index is proposed to detect cheating on multiple-choice examinations, and its use is evaluated through simulations. The proposed index is based on the compound binomial distribution. In total, 360 simulated data sets reflecting 12 different cheating (copying) situations were obtained and used for the study of the sensitivity of the index in…

Although computerized adaptive tests acquire their efficiency by successively selecting items that provide optimal measurement at each examinee's estimated level of ability, operational testing programs will typically consider additional factors in item selection. In practice, items are generally selected with regard to at least three, often…

Item response theory (IRT) model parameter estimates have considerable merit and open up new directions for test development, but misleading results are often obtained because of errors in the item parameter estimates. The problem of the effects of item parameter estimation errors on the test development process is discussed, and the seriousness…

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…

The theoretical differences between the traditional definition of dimensionality and the more recently defined notion of essential dimensionality are presented. Monte Carlo simulations are used to demonstrate the utility of W. F. Stout's procedure to assess the essential unidimensionality of the latent space underlying a set of terms. The…

Test scores that are not perfectly reliable cannot be strictly equated unless they are strictly parallel. This fact implies that tau equivalence can be lost if an equipercentile equating is applied to observed scores that are not strictly parallel. Thirty-six simulated data sets are produced to simulate equating tests with different difficulties…

Possible bias due to sampling problems or low response rates has been a troubling "nuisance" variable in empirical research since seminal and classical studies were done on these problems at the beginning of this century. Recent research suggests that: (1) earlier views of the alleged bias problem were misleading; (2) under a variety of fairly…

Two-stage and multistage test designs provide a way of roughly adapting item difficulty to test-taker ability. All test takers take a parallel stage-one test, and, based on their scores, they are routed to tests of different difficulty levels in subsequent stages. These designs provide some of the benefits of standard computerized adaptive testing…

Errors in item parameter estimates have a negative impact on the accuracy of item and test information functions. The estimation errors may be random, but because items with higher levels of discriminating power are more likely to be selected for a test, and these items are most apt to contain positive errors, the result is that item information…

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…

In computerized adaptive testing (CAT), new or experimental items are frequently administered alongside operational tests to gather the pretest data needed to replenish and replace item pools. The two basic strategies used to combine pretest and operational items are embedding and appending. Variable-length CATs are preferred because of the…

A small-scale study was conducted to compare test-taking strategies, problem-solving strategies, and general impressions about the test across computer and paper-and-pencil administration modes. Thirty-six examinees (high school students) participated in the study. Each examinee took a test in one of the content areas of English, Mathematics,…

The effects of a multidimensional latent trait space on estimation of item and person parameters by the computer program LOGIST are examined. Several item pools were simulated that ranged from truly unidimensional to an inconsequential general latent trait. Item pools with intermediate levels of prepotency of the general latent trait were also…

The proponents of test disclosure argue that disclosure is a matter of fairness; the opponents argue that fairness is enhanced by score equating which is dependent on test security. This research simulated disclosure on a professional licensing examination by placing response keys to selected items in some examinees' records, and comparing their…