Sex composition and group performance in a visual signal detection task

Forty-eight Ss (24 males, 24 females) were run in groups of 4 on 720 trials of a 16-alternative forced-choice visual signal detection task requiring both individual and group decisions. Four types of groups were formed: all male, all female, mixed-alternate (seated in the order male-female-male-female), and mixed-adjacent (seated in the order male-male-female-female). There were no differences in performance between all-male and all-female groups, but mixed-sex groups had poorer performance, with mixed-adjacent groups having significantly lower sensitivity than homogeneous-sex groups. The results were interpreted as indicating that heterogeneity of groups with regard to sex interacts with seating pattern in affecting performance, probably due to the formation of information coalitions between like-sex group members when the seating pattern encourages such coalitions.