In this paper, formulas for computing the weights that maximize the reliability of a test with multiple parts are derived using a congeneric model. A direct derivation for the three-part test and case and a two-step derivation for the n-part case are presented, and results for these two approaches are shown to be consistent for the three-part…

Person fit statistics are generated when item response theory is used to construct measures. While person fit statistics are well grounded in theory, their utility in aggregate reporting of survey data has not been demonstrated. This study evaluated effects on reliability and validity of including and excluding misfitting person response patterns,…

Three aspects of the usual approach to assessing local item dependency, Yen's "Q" (H. Huynh, H. Michaels, and S. Ferrara, 1995), deserve further investigation. Pearson correlation coefficients do not distribute normally when the coefficients are large, and thus cannot quantify the dependency well. In the second place, the accuracy of…

Previous studies have indicated that the reliability of test scores composed of testlets might be overestimated by conventional item-based reliability estimation methods (R. Thorndike, 1953; A. Anastasi, 1988; S. Sireci, D. Thissen, and H. Wainer, 1991; H. Wainer and D. Thissen, 1996). This study used generalizability theory to investigate the…

The benefits of item response theory (IRT) will only accrue to a testing program to the extent that model assumptions are met. Obtaining accurate item parameter estimates is a critical first step. However, the sample sizes required for stable parameter estimation are often difficult to obtain in practice, particularly for the more complex models.…

Noting that the amount of reading students do is related to their reading achievement, this booklet presents an instrument designed to measure the amount and breadth of students' reading in and out of school. The first part of the booklet discusses the Reading Activity Inventory (RAI) and how it differs from other reading activity measures, uses…

Using data collected through telephone interviews with a national sample of adults, this study searched for evidence as to whether interviewers have stronger effects on the responses given to a wide range of questions by older people than on the responses of younger people. Responses to 30 items for which significant interviewer effects had…

Evaluated with 12 children (9- to 25-months-old) were the efficacy and reliability of auditory stimulus-response control training and assessment procedures. (Author/LS)

This study determined internal consistency and test-retest reliability coefficients for the Willoughby Personality Schedule, currently used as an outcome measure in research and in clinical practice. The Hoyt analysis of variance yielded an internal consistency reliability coefficient of .90 on the first testing. The test-retest reliability…

Research indicates that a special version of the cloze procedure is a reliable test of reading comprehension. (RB)

Contrary to common belief, reliability estimates of number-right multiple-choice tests are not inflated by speededness. Because examinees guess on questions when they run out of time, the responses to these questions show less consistency with the responses of other questions, and the reliability of the test will be decreased. The surprising…

The usefulness of joint and conditional maximum-likelihood is considered for the Rasch model under realistic testing conditions in which the number of examinees is very large and the number is items is relatively large. Conditions for consistency and asymptotic normality are explored, effects of model error are investigated, measures of prediction…

Controversy over the proper place of significance testing within scientific methodology has continued for some time. The suggestion that effect sizes are more important than whether results are significant is presented. Effect size can be defined as an estimate of how much of the dependent variable is accounted for by the independent variables.…