The degree of acquaintance among group members (friends or strangers) and the opportunity for group members to observe each other's actions (anonymous or non-anonymous) were manipulated in a 2 x 2 factorial design, to determine the amount of aversive stimulation that would be administered to a target person. When group members could not observe…

Examined the interrelations of group contextual factors and the occurrence of aggressive behavior in 22 experimental play groups of 7- and 9-year-old African American boys. Found that negative affect, high aversion behavior, high activity level, low group cohesion, and competitiveness were related to the occurrence of aggressive behavior. (MDM)