Many experimental designs in educational and behavioral research involve at least one level of clustering. Clustering affects the precision of estimators and its impact on statistics in cross-sectional studies is well known. Clustering also occurs in longitudinal designs where students that are initially grouped may be regrouped in the following…

There were two purposes for this mixed methods study: to investigate (a) the realistic meaning of awareness and understanding as the underlying constructs of general knowledge of the learning process and (b) a procedure for data consolidation. The participants were 11th-grade high school and first-year university students. Integrated data…

This study focused on how two algebraic concepts- equality and variable- predicted 8th grade students' equation solving performance. In this study, predictive design as a correlational research design was used. Randomly selected 407 eight-grade students who were from the central districts of a city in the central region of Turkey participated in…

The identification of evidence-based practices continues to provoke issues of disagreement across multiple fields. One area of contention is the role of single-subject design (SSD) research in providing scientific evidence. The debate about SSD's utility centers on three issues: sample size, effect size, and serial dependence. One potential…

Current research suggests a link between negative attitudes toward women and violence against women, and it also suggests that media may condition such negative attitudes. When considering the tremendous and continued growth of video game sales, and the resulting proliferation of sexual objectification and violence against women in some video…

A correlational explanatory research design examined the relationship between peer mentoring, academic success and social engagement of first year college students participating in a peer mentoring program at a research one university in the southeastern United States. One hundred thirty-eight participants from the peer mentoring program responded…

The purpose of this study was to determine if English Language Learner (ELL) reading achievement scores could be related to the group's participation in Response to Intervention (RTI). RTI addresses the challenges many public schools face as they seek the best methods for teaching reading and language while facing a nationally significant…

A common mistake in analysis of cluster randomized experiments is to ignore the effect of clustering and analyze the data as if each treatment group were a simple random sample. This typically leads to an overstatement of the precision of results and anticonservative conclusions about precision and statistical significance of treatment effects.…

A previous Monte Carlo study examined the relative powers of several simple and more complex procedures for testing the significance of difference in mean rates of change in a controlled, longitudinal, treatment evaluation study. Results revealed that the relative powers depended on the correlation structure of the simulated repeated measurements.…

Written by a social worker for social work students, this is a nuts and bolts guide to statistics that presents complex calculations and concepts in clear, easy-to-understand language. It includes numerous examples, data sets, and issues that students will encounter in social work practice. The first section introduces basic concepts and terms to…

A Monte Carlo technique was used to investigate the effect of the differences in covariate means among treatment groups on the significance level and the power of the F-test of the analysis of covariance. (Author/GDC)

Investigates sample size requirements needed to achieve various levels of statistical power using posttest-only, gain-score, and analysis of covariance designs in evaluating training interventions. Results indicate the power to detect true effects differ according to type of design, correlation between pre- and posttest, and size of effect due to…

Against an historical backdrop, this paper summarizes four uses of intraclass correlation of importance to contemporary researchers in the behavioral sciences. First, it shows how the intraclass correlation coefficient can be used to adjust confidence intervals for statistical significance testing when data are intracorrelated and the independence…

Multiple regression analysis is frequently being employed in experimental and non-experimental research. However, when data include predictor variables that are correlated, some regression results can become difficult to interpret. This paper presents a study to provide a demonstration that structure coefficients may be useful in these cases.…

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.…