For decades, research has shown that higher levels of education correspond to increased interest in politics and civic engagement. Despite the vast amount of scholarly attention, why this link exists is still disputed. One theory about the connection is the civic education hypothesis, which claims that the causal link between education and civic…

A new effect size representing the predictive power of an independent variable from a multiple regression model is presented. The index, denoted as r[subscript sp], is the semipartial correlation of the predictor with the outcome of interest. This effect size can be computed when multiple predictor variables are included in the regression model…

Since Piaget, the view that motor and cognitive development are interrelated has gained wide acceptance. However, empirical research on this issue is still rare. Few studies show a correlation of performance in cognitive and motor tasks in typically developing children. More specifically, Diamond A. (2000) hypothesizes an involvement of executive…

Measures of head injury, executive functioning, and intelligence were given to a community sample composed of 102 male perpetrators of intimate partner aggression (IPA) and 62 nonaggressive men. A history of head injury and lower mean score on a measure of verbal intelligence were associated with the frequency of male-perpetrated physical IPA as…

Individual differences in measures of prereading skills and in questionnaire measures of 4-5-year-old twins' print environments in Australia, Scandinavia, and the United States were explored with a behavioral-genetic design. Modest phenotypic correlations were found between environmental measures and the twins' print knowledge, general verbal…