When the errors in an ordinary least squares (OLS) regression model are heteroscedastic, hypothesis tests involving the regression coefficients can have Type I error rates that are far from the nominal significance level. Asymptotically, this problem can be rectified with the use of a heteroscedasticity-consistent covariance matrix (HCCM)…

Previous research on nonspecific transfer of training is reviewed in terms of its implications for ability training. Specific focus is on the question of improving general abilities through training on related but nonidentical tasks. Studies selected include experimental, laboratory studies as well as research carried out in a number of applied…

The study evaluates the effectiveness of a set of social studies activities in promoting cooperative interaction among junior high school students. A field experiment was designed to test three hypotheses: (1) groups which have previously worked together structure tasks more cooperatively than a newly formed group: (2) groups which have…