Methods for the analysis of within-subjects effects in multivariate groups by trials repeated measures designs are considered in the presence of heteroscedasticity of the group variance-covariance matrices and multivariate nonnormality. Under a doubly multivariate model approach to hypothesis testing, within-subjects main and interaction effect…

The Division of Applied Research of the National Institute on Drug Abuse sponsored a Consensus Conference at which key technical, scientific, and procedural issues of employee drug testing could be discussed. The conference, which included politicians and government officials; representatives of business, industry, and labor; and laboratory…

A selection of statistical problems commonly encountered in psychological or psychiatric research concerning correlation coefficients are re-evaluated in the light of recently developed simplifications in the forms of the distribution theory of the intraclass correlation coefficient, of the product-moment correlation coefficient, and the Spearman…

In some situations where reliability must be estimated it is impossible to divide the measuring instrument into more than two separately scoreable parts. In such a case, neither Cronbach's coefficient alpha nor Kristof's three-part approach are satisfactory. A technique is developed for estimating reliability in such situations. (Author/BJG)

Two experiments examined the hypothesis that the average of group members' responses following group discussion will generally be more extreme in the same direction as the average of individual pregroup preferences. (Author/MLF)

Notetakers showed superior posttest recall, and notetaking without test instructions yielded the best group performance. (RC)

This article discusses six post-1915 educational benchmarks a) the Socialized Recitation; b) the Testing Movement; c) Individualizing Instruction; d) Project Method and Activity Schools; e) the Eight-Year Study; and f) the United States Armed Forces Institute (USAFI). (JA)

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)

The theory of projective transformation is applied to the Rasch model for representing test performances. (Author/RC)

Significant differences in performance due to task definition were found only on verbal tasks with test instructions yielding superior performance. (Author/RC)

Compared Edwards Personality Inventory (EPI) reliability under the Edwards' instructions (subject responds to the items as he believes those who know him best would answer if asked to describe him) versus the more conventional instructions (to describe yourself directly as you see yourself). (Author/RC)

The purposes of this study were to determine: (1) the effectiveness with which different types of rehearsal strategies complementing visualized instruction facilitate student achievement; (2) the effect of different instructional treatments on students' processing of different knowledge levels; and (3) whether verbal and visual tests are equally…

In analyzing exploratory repeated measures data with more than two measures, two competing tests must be administered simultaneously if one is to make an efficient and effective decision regarding the tenability of the null hypothesis of no differences among measurement means. Obviously, such a procedure is not without a cost vis-a-vis Type I…

A set of general principles underlying theory formation, theory revision, and experimentation are described. The manner in which these techniques may be integrated to provide a unified and comprehensive treatment of scientific theory development is demonstrated. In particular, the means by which experimentation is used to empirically guide and…