Differential bundle functioning (DBF) has been proposed to quantify the accumulated amount of differential item functioning (DIF) in an item cluster/bundle (Douglas, Roussos, and Stout). The simultaneous item bias test (SIBTEST, Shealy and Stout) has been used to test for DBF (e.g., Walker, Zhang, and Surber). Research on DBF may have the…

A common assumption in meta-analysis is that effect sizes are independent. When correlated effect sizes are analyzed using traditional univariate techniques, this assumption is violated. This research assesses the impact of dependence arising from treatment-control studies with multiple endpoints on homogeneity measures "Q" and…

We examined the degree of dependence between standardized-mean-difference effect sizes in multiple-treatment studies in meta-analysis in terms of the correlation formula provided by Gleser and Olkin (1994). To explore the impact of group size and the values of the true multiple-treatment effect sizes, we simplified the formula for the correlation…

In this study, differential item functioning (DIF) trends were examined for English language learners (ELLs) versus non-ELL students in third and tenth grades on a large-scale reading assessment. To facilitate the analyses, a meta-analytic DIF technique was employed. The results revealed that items requiring knowledge of words and phrases in…

A new approach is presented for the meta-analysis of data from pre-test/post-test designs. With this approach, data from studies using different designs may be compared directly and studies without control groups need not be omitted. The approach is based on a "standardized mean-change" measure, computed for each sample within a study,…

The random variable p and its functions figure in several "tests of combined significance," meta-analysis summaries based on sample significance values, and ps have been used singly, as well as in other tests for evaluating the outcomes of individual research studies. In this work, asymptotic distributions of the sample one-sided…

This meta analysis examined the results of 24 studies in which traditionally certified teachers were compared with teachers with a variety of other kinds of certificates. The 24 studies allowed for the computation of 192 effect sizes, and 7 kinds of comparison were performed. Findings suggest that traditional teacher training is at least as…

Power is an indicator of the ability of a statistical analysis to detect a phenomenon that does in fact exist. The issue of power is crucial for social science research because sample size, effects, and relationships studied tend to be small and the power of a study relates directly to the size of the effect of interest and the sample size.…

This article extends both the logic and the statistical procedures used in a recent analysis of Hyde's data on gender differences in cognitive abilities by Rosenthal and Rubin. The logic of a "model fitting" approach to meta-analysis is described. Relevant statistical procedures and goodness-of-fit tests are illustrated. (Author/BS)

Differences in science achievement between males and females have been examined either directly or indirectly in a variety of studies. This investigation reviewed a quantitative synthesis of correlational research on science affect, ability, and achievement conducted by Steinkamp and Maehr. Their findings were reassessed by employing a…

Data from 30 studies involving gender differences related to science achievement were synthesized using analyses of effect sizes and vote-counting estimation procedures. Reports that males showed advantages in biology, general science, and physics. (Author/YP)

Analyses of the results of 23 reports on coaching for the Scholastic Aptitude Test (SAT) indicated that, on the average, coaching can help increase SAT scores. The considerable variability in the results of 48 studies reflected the many factors influencing coaching effectiveness and the wide variety of study designs. (SLD)

Data drawn from 30 journal articles and ERIC documents reporting on gender differences in natural science achievement were re-examined. Three meta-analysis methods were used: (1) vote counts and vote-counting estimation procedures; (2) tests of combined significance; and (3) analyses of effect sizes. The three methods produced seemingly…