When comparing two tests that measure the same trait, separate comparisons should be made at different levels of the trait. A simple, practical, approximate formula is given for doing this. The adequacy of the approximation is illustrated using data comparing seven nationally known sixth-grade reading tests. (Author/RC)

A variety of practical applications of item characteristic curve test theory are discussed. Among these applications are tailored testing, two stage testing, determining whether two tests measure the same latent trait, and measuring item bias towards minority or other groups. (Author/JKS)

Two approaches for determining the optimal number of choices for a test item, presently in the literature, are compared with two new approaches. (Author)

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)

Advantages and disadvantages of joint maximum likelihood, marginal maximum likelihood, and Bayesian methods of parameter estimation in item response theory are discussed and compared. (Author)

Four methods are outlined for estimating or approximating from a single test administration the standard error of measurement of number-right test score at specified ability levels or cutting scores. The methods are illustrated and compared on one set of real test data. (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…