We develop a Roy model of social interactions in which individuals sort into peer groups based on comparative advantage. Two key results emerge: First, when comparative advantage is the guiding principle of peer group organization, the effect of moving a student into an environment with higher-achieving peers depends on where in the ability…

Although use is a core construct in the field of evaluation, neither the change processes through which evaluation affects attitudes, beliefs, and actions, nor the interim outcomes that lie between the evaluation and its ultimate goal--social betterment--have been sufficiently developed. We draw a number of these change mechanisms, such as…

A self-report inventory was compared with a situational test as a predictor of the verbal behavior of individual members of small interpersonal skills training groups. As hypothesized, the situational test was a better predictor than was the self-report inventory. A powerful social conformity effect may have operated in both the situational test…