Factorial modeling is justified as a method for analyzing correlations in support of causal inference. The method is illustrated and compared to path analysis, LISREL-type analysis, canonical correlation, and commonality analysis. Predictions of impacts of policy manipulations are demonstrated. (Author/CP)

Contrary to Anderson (EJ 187 936), his rule for equation identification is a necessary but not sufficient condition; furthermore, the choice of two-stage or ordinary least squares depends on results and not on methodological properties of estimators. Modification of Anderson's rule and a means for choosing between estimates is offered. (Author/CP)

Classrooms that used different instructional approaches to mathematics were observed, contrasting instruction that aimed to promote conceptual understanding rather than algorithmic skill with more conventional instruction. Results with 6 second-grade classrooms (135 students) suggest that relationships between teaching and learning are a function…

Effects of previous training and experience in peer tutoring on student interactions were studied for 16 elementary school classes. Student dyads with experience and training in peer tutoring provided more interactional explanations and incorporated sounder instructional principles. In both situations, student explanations tended to be algorithmic…