Mediation is usually assessed by a regression-based or structural equation modeling (SEM) approach that we refer to as the classical approach. This approach relies on the assumption that there are no confounders that influence both the mediator, "M", and the outcome, "Y". This assumption holds if individuals are randomly…

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…

Controversy surrounds the ranking of crime seriousness of white-collar crimes relative to street crimes, with early research suggesting the general public is indifferent to crimes of the elite, whereas more recent research indicates that the public thinks certain types of white-collar crime are serious. Building on prior research limitations and…

This article presents a discussion of mixed methods (MM) sampling techniques. MM sampling involves combining well-established qualitative and quantitative techniques in creative ways to answer research questions posed by MM research designs. Several issues germane to MM sampling are presented including the differences between probability and…

The stability of standard score and probability method sociometric group assignments was examined over a two-year period with an initial group of 334 fifth graders. Popular, neglected, and controversial groups evidenced low stability of group members over intervals of approximately 1, 6, 12, 18, and 24 months. (Author/RH)

Introduces two data distortion methods (Frequency-Imposed Distortion, Frequency-Imposed Probability Distortion) and uses a Monte Carlo study to compare their performance with that of other distortion methods (Point Distortion, Probability Distortion). Indications that data generated by these two methods produce accurate statistics and protect…