Group cohesiveness, social norms, and bystander intervention.

Previous research suggests that the larger a group of bystanders is, the less likely any one bystander is to offer a victim help in an emergency. Nearly all of this research has been conducted with unacquainted bystanders, and thus, an im-portant group characteristic, cohesiveness, may have been held at a low level. Study 1 found support for the hypothesis that group size inhibits helping in low-cohesive groups but facilitates helping in high-cohesive groups. Study 2 found support for the hypothesis that the effects of cohesiveness on bystander interven-tion depend on the salience of the social-responsibility norm: Cohesiveness fa-cilitated helping more when the social-responsibility norm was salient than when it was not. Thus * group cohesiveness is a theoretically critical variable for un-derstanding the bystander effect. The results of these experiments suggest that the effects of group and situation variables depend on the groups meaning to the individual. Latan £ and Darley (1970) conducted a se-ries of investigations to test the relation be-