The "factor" analyses published by Schultz, Kaye, and Hoyer (1980) confused component and factor analysis and led to unwarranted conclusions. The principal factors method yields two factors which support the a priori expectation of a difference between intelligence tasks and spontaneous flexibility tasks. (Author/RD)

Proposes a means for determining the similarity between search request formulations in online information retrieval systems, and discusses the use of similarity measures for clustering search formulations and document files in such systems. Experimental results using the proposed methods are presented in three tables. A reference list is provided.…

Appropriate methods are described for research workers in sociology to use as they perform causal analyses of data from surveys. Particular emphasis is placed on the causal analysis of qualitative variables. (Author/DB)

Computer simulations indicate that the correlation between baseline and change, by itself, does not invalidate the use of gain scores to measure change, but when the negative correlation is accompanied by decrease in variance from pretest to posttest, covariance is a superior measure of change. (SLD)

Alternative tests are presented for the between-by-within interaction null hypothesis and for two within-subjects main effects null hypothesis in a split plot design. Estimated Type I error rates for the interaction tests and for several tests of the second null hypothesis are reported. (SLD)

A data set (4,398 drug offenders from Florida) is used to estimate impacts of probation and imprisonment on recidivism and to explore the impact of biases related to selection and interruption of the duration of probation. Correcting for these biases leaves no evidence that probation impacts on duration of recidivism. (SLD)

The present simulation study confirms that the corrected epsilon approximate test of B. Lecoutre yields a less biased estimation of population epsilon and reduces Type I error rates when compared to the epsilon approximate test of H. Huynh and L. S. Feldt. (SLD)

The use of p-values in combining results of studies often involves studies that are potentially aberrant. This paper proposes a combined test that permits trimming some of the extreme p-values. The trimmed statistic is based on an inverse cumulative normal transformation of the ordered p-values. (SLD)

The derivation of the variance of similarity judgments is made from the 3-D process in nonlinear psychophysics. The idea of separability of dimensions in metric space theories of similarity is replaced by one parameter that represents the degree of a form of interdimensional cross-sampling. (SLD)

The test proposed by Brien, Venables, and Mayo (1984), endorsed by Silver and Dunlap, and supported by computer software that they developed is not a proper test for multivariate independence. A revised appraisal is suggested for the Silver and Dunlap results. (SLD)

Education statistics are rarely neutral; those who collect and analyze them have different purposes. In this article, Bracey discusses several principles of data interpretation to help educators avoid falling into statistical traps. For example, because such reports as A Nation At Risk contain many "selected, spun, distorted, and even manufactured…

The need for using invariance procedures to establish the external validity or generalizability of statistical results has been well documented. Invariance analysis is a tool that can be used to establish confidence in the replicability of research findings. Several approaches to invariance analysis are available that are broadly applicable across…

The concept of control is fundamental to comparative research. In research designs where randomization of observational units is not possible, control has been exercised statistically from a single covariate by a process of residualization. The alternative, known as subclassification on the propensity score, was developed primarily for…

Presents an examination of graduate admissions data with various analysis techniques. Aggregate data showed a clear but misleading bias against female applicants. When data were properly pooled it was found that there was a small but significantly significant bias in favor of women. (GS)

This chartbook is designed as a graphic reference on national statistical information about disabilities. Each page contains a content question, explanatory text, and an explanatory chart or table as well as information on sources used. Key terms are shown in boldface and defined in a glossary. Section 1 provides demographic data on Americans with…