Drabman, R. S., & Thomas, M. H. (1977). Children’s imitation of aggressive and prosocial behavior when viewing alone and in pairs. Journal of Communication, 27 (3), 199-205.

Abstract:  Compared the behavior of 40 5-yr-old Black males who viewed a 3.5-min prosocial or aggressive film individually or in pairs. The aggressive film showed an adult male physically and verbally assaulting an adult costumed as a clown. The prosocial film showed the model and clown engaging in friendly and cooperative play. The Ss, individually or in pairs, then participated in a 5-min free play session in an experimental room containing both the adult clown and the toys seen in the film. Ss who participated in pairs showed more aggression than those who participated alone. Aggression toward the clown was higher for those who watched the aggressive film. Ss who viewed the prosocial film engaged in more constructive play, particularly for those participating in pairs. There was no difference between individuals and pairs in prosocial behavior for those Ss in the aggressive film condition. (PsycINFO Database Record (c) 2004 APA, all rights reserved)