This study meta-analytically examined extensive literature associated with work commitment. The primary purposes were to (a) cumulate correlations among dimensions of work commitment to see which were intercorrelated and (b) determine impact of work commitment dimensions and subdimensions on specific outcome variables (job satisfaction, job…

Background: A key issue in the nosology of attention deficit hyperactivity disorder (ADHD) has concerned whether the DSM-IV combined (ADHD-C) and primarily inattentive (ADHD-PI) subtypes are in fact distinct disorders, or instead are fairly closely related, perhaps differing only in severity. Pertinent to this question, but in short supply, are…

We examined 3- to 6-year-old children's understanding of their own and another's false beliefs in two experiments using diverse deceptive box and unexpected transfer tasks. Tasks in the first experiment required the child to think about an absent person's responses to questions, whereas those in the second experiment used a confederate present…

Sex differences in cognition are consistently reported, men excelling in most visuospatial tasks and women in certain verbal tasks. It has been hypothesized that these sex differences in cognition results from a more bilateral pattern of language representation in women than in men. This bilateral pattern of language representation in women is…

The meta-analytic random effects model assumes that the variability in effect size estimates drawn from a set of studies can be decomposed into two parts: heterogeneity due to random population effects and sampling variance. In this context, the usual goal is to estimate the central tendency and the amount of heterogeneity in the population effect…

Are preventive early childhood interventions effective in improving home environments, as assessed with the HOME inventory (Caldwell & Bradley, 1984)? The authors traced 48 published articles, presenting 56 intervention effects (N = 7,350). The combined effect size on the HOME total score was d = 0.20 (p less than 0.001). Randomized…

A meta-analysis is presented of 57 studies of sex differences in general population samples on the Standard and Advanced Progressive Matrices (SPM and APM, respectively). Results showed that there is no difference among children aged 6-14 years, but that males obtain higher means from the age of 15 through to old age. Among adults, the male…

This article presents a brief overview of existing research on the effects of exposure to violent video games. An updated meta-analysis reveals that exposure to violent video games is significantly linked to increases in aggressive behaviour, aggressive cognition, aggressive affect, and cardiovascular arousal, and to decreases in helping…

[Groot and Maassen van den Brink, 2000a] provide a useful summary of the incidence of overeducation and undereducation. Unfortunately, by combining non-compatible estimates of the impact of surplus schooling (and under schooling) on earnings they potentially bias their estimates downward (upward). This paper bypasses this potential bias by…

For decades a substantial body of research on teacher reflection and action has been conducted. This research contains a wealth of information on teachers' thinking about their daily work in classrooms. But what do these studies tell us about the linkage between thought and action in actual teaching? How do they contribute to our understanding, or…

This meta-analysis synthesizes the available data on the strength of association between anger and posttraumatic stress disorder (PTSD) and between hostility and PTSD, covering 39 studies with trauma-exposed adults. Effect sizes did not differ for anger and hostility, which could therefore be combined; effect sizes for anger expression variables…

Algebra student achievement has become a matter for increased focus in recent years, as educators answer calls for reform, including the standards documents of the National Council of Teachers of Mathematics and the No Child Left Behind mandates. A meta-analysis of 35 independent experimental studies shows that six teaching method categories have…

The field of research on computer-mediated communication (CMC) in education is a relatively new research area. A summary of the latest research is useful to show what methodologies and research topics have been emphasized in order to be better prepared for the future by uncovering areas where there is a lack of research. The study examines…

This article summarizes the results of a recent role and function study completed in 2004 to determine the prevailing domains of disability management practice. The study also sought to establish an empirical basis for a certification exam for disability management specialists consistent with evolving standards of practice. Based on the expert…

Animation of various types has been used increasingly in different disciplines in computer-based learning environments to facilitate achievements of different kinds of learning objectives. However, the result of empirical animation studies has been mixed and mostly discouraging. The purpose of this meta-analysis was to examine the instructional…