This paper includes a nontechnical description of methods for calculating effect sizes in intellectual and developmental disability studies. Different hypothetical studies are used to illustrate how null hypothesis significance testing (NHST) and effect size findings can result in quite different outcomes and therefore conflicting results. Whereas…

Using a Monte Carlo approach, comparison was made between traditional procedures and a multiple linear regression approach to test for differences between values of r sub 1 and r sub 2 when sample data were dependent and independent. For independent sample data, results from a z-test were compared to results from using multiple linear regression.…

A growing controversy surrounds the strict interpretation of statistical significance tests in social research. Statistical significance tests fail in particular to provide estimates for the stability of research results. Methods that do provide such estimates are known as invariance or cross-validation procedures. Invariance analysis is largely…

This paper discusses distribution theory and power computations for four common "tests of combined significance." These tests are calculated using one-sided sample probabilities or p values from independent studies (or hypothesis tests), and provide an overall significance level for the series of results. Noncentral asymptotic sampling…

Hypothetical data sets are used to demonstrate how canonical correlation methods subsume other commonly utilized parametric methods. Analysis of variance, analysis of covariance, multiple analysis of variance, and multiple analysis of covariance are heavily used by educational researchers. It is concluded that researchers would do well to consider…

The study reported in this paper examined whether a disproportionate number of boys and girls in a given grade level at various schools might have an inequitable effect on the mean achievement test scores of those schools. The student population of the Palm Beach County Schools, Florida, reflecting a cross-section of socio-economic backgrounds,…

Describes development and operation of the University of Missouri's Center for Independent Study; its implementation and use of online computer assisted instruction; and a study comparing student attitudes toward online computer assisted instruction and correspondence courses. (MBR)

The purpose of this study was to investigate the effectiveness of computer-aided instruction as compared with the traditional lecture method of cognitive learning of new curriculum materials. It was hypothesized that students instructed by the computer-aided instruction method would gain higher knowledge of the subject matter in terms of cognitive…

To examine the validity of short forms of the Wechsler Intelligence Scale for Children-Revised (WISC-R), the WISC-R was first administered to 106 hospitalized psychiatric patients, aged 8-16. No subjects had a primary diagnosis of mental retardation or learning disability, and one-third were receiving psychotropic medication. WISC-R IQ scores…

This study used the restricted access database of the 1993 National Study of Postsecondary Faculty to examine faculty workload by academic discipline for full-time regularly appointed teaching and research faculty in public Carnegie research I and II and Doctoral I and II institutions (n=2,056). Data are reported for 14 disciplinary areas…

Statistical significance is misused in educational and psychological research when it is applied as a method to establish the reliability of research results. Other techniques have been developed which can be correctly utilized to establish the generalizability of findings. Methods that do provide such estimates are known as invariance or…

This study investigated the use of teacher perceptions of school effectiveness variables as part of the Pennsylvania state assessment program and briefly reviewed the teacher survey instrument development. Data were available for 155 of the 500 school districts from the 1985 Educational Quality Assessment administration. A norm sample included 111…