In his early exposition of path analysis, Duncan (1966) noted that the method "provides a calculus for indirect effects." Despite the interest in indirect causal effects, most users treat them as if they are population parameters and do not test whether they are statistically significant. Sobel (1982) has recently derived the asymptotic…

Describes aptitude treatment interaction study that used the cognitive styles field dependence and independence matched with computerized algorithmic and discovery treatments to determine mathematics achievement on a criterion-referenced test. Posttest mathematics scores and student responses to the computer are analyzed, and mastery learning is…