In psychological research, one often aims at explaining individual differences in S-R profiles, that is, individual differences in the responses (R) with which people react to specific stimuli (S). To this end, researchers often postulate an underlying sequential process, which boils down to the specification of a set of mediating variables (M)…

Research investigations on teacher training effects have focused almost exclusively on differences between group means. The present paper suggests that several interesting and important research questions might be answered by examining student variability both within and between classrooms. Student variability might be considered as an outcome to…

In this review of the research on how current computer learning environments can foster the acquisition of complex cognitive skills, two issues emerge: (1) what cognitive accomplishments are likely in the computer environment; and (2) what factors predispose students to benefit from the environment. (MBR)