The Ringelmann effect: Studies of group size and group performance

Abstract

Ringelmann's classic finding—that the addition of co-workers in a rope-pulling task leads to a linear decrement in the individual group member's average performance—was reexamined experimentally. Study I attempted to replicate the effect, using groups of subjects ranging in size from 1 to 6. Performance dropped significantly as group size was increased from one individual to two or to three, but the addition of a fourth, fifth, or sixth member produced insignificant additional decrements; thus, the effect was not linear but curvilinear. Study II was designed to examine possible sources of performance loss, separating the factors of “coordination” and “motivation” loss (Steiner, 1972). The possibility of intermember incoordination was eliminated, while motivation loss remained free to vary: Each experimental subject pulled alone, and in “groups” where he believed there were from one to five other members. Once again, individual performance declined significantly with the addition of the first and second perceived co-worker, but then leveled off for perceived group sizes three to six. Some implications are discussed.