Researchers across many fields have called for greater attention to heterogeneity of treatment effects--shifting focus from the average effect to variation in effects between different treatments, studies, or subgroups. True heterogeneity is important, but many reports of heterogeneity have proved to be false, non-replicable, or exaggerated. In…

The relationships between a diverse set of individual difference, demographic, and aptitude variables; and a set of student attitudes and behaviors pertinent to experiences in large lecture classes were examined. The sample was 4300 students enrolled in 33 lecture classes at a large university. The relationship between the set of individual…

A study examined the effects of two factors--learner ability and modifications of instruction through increased feedback and reduced size of instructional units--on the time required for learning and the retention of fourth-grade male students. While instructional modifications best predicted the time needed for learning, learner ability best…

To ascertain changes in cognitive correlates of learning as students advance through hierarchical instruction, 24 individual difference measures were obtained from 166 Navy trainees who had completed a computer-managed course in electricity and electronics. Principal component analysis and varimax rotation were computed for cognitive…

Student ability, involvement in the class, and classroom climate created by the instructor activities were examined as multiple and interactive predictors of course performance for 915 students in 74 sections of an undergraduate mathematics course. Climate was defined in two ways: (1) as individual perceptions and (2) as shared perceptions. Two…

Students' macroprocessing of instruction was studied in a learning situation which used adjunct questions. The subjects were offered various macroprocessing options while reading a passage on data processing and computer programming. Each sentence appeared on a computer CRT screen one at a time. The options included: (1) review any sentence or…

Relationships between cognitive and affective learner characteristics or "aptitudes" and mathematics achievement for sixth-graders in three instructional treatments in one school district were examined. Aptitude-treatment interaction (ATI) analyses were performed to test for differential prediction of achievement outcomes among treatments, using…