Reluctance to use group mean as the unit of analysis is partly due to the belief that fewer observations per treatment greatly reduces the probability of detecting a treatment effect. This is discussed; equations are presented to facilitate power estimates when the group mean is the unit of analysis. (Author/BW)

Statistical techniques for summarizing results from independent correlational studies are presented. The case in which only the sample correlation coefficients are available and the case in which the original paired data are available are both considered. (Author/JKS)

Discusses difficulties encountered in use of the Scheffe procedure to locate the most significant parametric function within a linear statistical model that has been tested and rejected by, for example, analysis of variance. A solution to the problems is presented. (TJH)

Several randomized response models for gathering self-report data when persons are asked sensitive questions are reviewed. A new general model for reducing error by asking questions conditional upon earlier answers is introduced. Hypothesis testing and confidence-interval procedures are demonstrated for data collected by the randomized response…

Seven univariate procedures for testing omnibus null hypotheses for data gathered from repeated measures designs were evaluated, comparing five alternative approaches with two more traditional procedures. Results suggest that the alternatives are improvements. The most effective alternate procedure in controlling Type I error rates is discussed.…

The method of unweighted means in the multivariate analysis of variance with unequal sample sizes was investigated. By approximating the distribution of the hypothesis sums-of-squares-and-cross-products with a Wishart distribution, multivariate test statistics were derived. Monte Carlo methods and a numerical example illustrate the technique.…

For the conditions investigated in the study, the parametric ANCOVA was typically the procedure of choice both as a test of equality of conditional means and as a test of equality of conditional distributions. (Author/LMO)

The use of statistical methods to combine the results of independent empirical research studies (metanalysis) has a long history, with work mainly divided into tests of the statistical significance of combined results and methods for combining estimates across studies. Methods of metanalysis and their applications are reviewed. (SLD)

A detailed investigation is provided of Stout's statistical procedure (the computer program DIMTEST) for testing the hypothesis that an essentially unidimensional latent trait model fits observed binary item response data from a psychological test. Three refinements achieve greater power. The revised approach is validated using real data sets.…