The effects of goal setting and group size on performance in a social dilemma

The effect of self-set personal and assigned group goal setting on an indiv idual's behaviour in 3- and 7-person groups confronted with a social dilemm a was investigated. Participants (N = 274) earned between $1.82 and $4.94 b y investing money in either a personal account or a group account. Serf-set personal goals that were compatible with an assigned group goal led to hig her group performance than self-set incompatibly high ("greedy") personal g oals. Collective-efficacy in making money, outcome expectancies that cooper ation with others leads to the attainment of the group's goal, and group go al commitment correlated positively with group performance. Individuals in 7-person groups (N = 28) were less cooperative than those in 3-person group s (N = 26). They had lower collective-efficacy, lower outcome expectancies, and lower commitment to the group goal than did individuals in 3-person gr oups. Furthermore, individual performance in 7-person groups was significan tly lower than individual performance in 3-person groups. A social dilemma appears to be a boundary condition for the normally positive effect of grou p goal setting on group performance.