bystander effect

trolley problem

crowd

group

groupthink

is a social psychological phenomenon that refers to cases in which individuals do not offer any means of help to a victim when other people are present. The probability of help is inversely related to the number of bystanders.

The bystander effect, or bystander apathy, is a social psychological phenomenon that refers to cases in which individuals do not offer any means of help to a victim when other people are present. The probability of help is inversely related to the number of bystanders. (wikipedia)

is actually an an entirely rational response, and contrary to apathy, bystanders only become bystanders if they decided sufficient help had already been given.

The bystander effect, the phenomenon that the (real or imagined) presence of others inhibits helping, has often been ascribed to bystanders' apathy. In the present research, we demonstrate that the occurrence of the bystander effect has rational roots. Three studies reveal that the presence of other bystanders does not inhibit helping when effective helping requires more than one help-giver. Mediation analyses showed that the bystander effect did not occur when many responses were needed because bystanders did not shift responsibility to others when in the presence of other bystanders. These findings suggest that the rational considerations underlying the bystander effect can mitigate the effects of the presence of other bystanders on helping behaviour when more than one help-giver is needed.

bystander effect, n.Definitions

bystander effect