Twin children were videotaped hitting an inflated clown figure. Three behaviors (number of hits, intensity of hits, and number of quadrants hit) showed adequate response characteristics, rater reliability, and test-retest reliability. Twin analyses of the three behavioral ratings yielded no evidence of hereditary influence. (Author)

Tested the hypothesis that internals will achieve more than externals in situations where competition is preeminent but not where cooperation is requried. Children (N=300) were divided into internals and externals, placed in situations varying in competition and cooperation, and readministered digit-symbol task. The general hypothesis was…

Reviews literature on effects of being imitated and the social influence function of imitation, plus related literature on conformity from social psychology. Considers this research within a number of theoretical contexts, especially within the conceptual framework of effectance motivation. Suggests imitation may facilitate mastery and control of…