A statistical test for cheating is developed. The case of a single examinee who has taken parallel forms of the same selection test on three occasions, obtaining scores x, y, z, is used to illustrate the development. It is assumed that each score is normally distributed with the same known variance, that is, the variance of the errors of…

Certain modifications of a conventional test are proposed which force the item difficulty level to adjust automatically to the ability level of the examinee. The modified test is called a flexilevel test. Although different examinees take different sets of items, the scoring method provides comparable scores for all. Furthermore, the test is…

For the six available sets of empirical data, the discrimination (slope) parameter of the logistic item characteristic curve was found to have a significant positive correlation over items with the difficulty (location) parameter. This unpleasant situation can be eliminated by a suitably chosen transformation of the ability scale. (Author/RC)

A general Computer program is described that will compute asymptotic standard errors and carry out significance tests for an endless variety of (standard and) nonstandard large-sample statistical problems, without requiring the statistician to derive asymptotic standard error formulas. The program assumes that the observations have a multinormal…

A new formula, expressing relative efficiency solely in terms of the standard errors of measurement and the frequency of distributions of true scores, is developed for the relative efficiency of two tests measuring the same trait. Subtests from the Scholastic Aptitude Test provide a numerical illustration. (Author/RC)

An elementary survey of item characteristic curve theory, centered around the problems of individualized (tailored) testing, is presented. Following the introduction, discussions are provided of the following: Test Theory for Itemized Tests; The Guttman Scale; Item Characteristic Curve Theory; An Alternative Model; Specialization, Application, and…

A new formula is developed for the relative efficiency of two tests measuring the same trait. The formula expresses relative efficiency solely in terms of the standard errors of measurement and, surprisingly, the frequency distributions of true scores. Approximate methods for estimating relative efficiency may make this function routinely…

The assumption that examinees either know the answer to a test item or else guess at random is usually totally implausible. A different assumption is outlined, under which formula scoring is found to be clearly superior to number right scoring. (Author)

There are currently three main approaches to parameter estimation in item response theory (IRT): (1) joint maximum likelihood, exemplified by LOGIST, yielding maximum likelihood estimates; (2) marginal maximum likelihood, exemplified by BILOG, yielding maximum likelihood estimates of item parameters (ability parameters can be estimated…

A method for estimating power scores is described. By way of illustration, it is applied to 21 students who were improperly timed on a standard test. Some empirical results are given in support of the estimation procedure. (Author)

Modifications of administration and item arrangement of a conventional test can force a match between item difficulty levels and the ability level of the examinee. Although different examinees take different sets of items, the scoring method provides comparable scores for all. Furthermore, the test is self-scoring. These advantages are obtained…