The effects of undermanning on group behavior

This study was made in order to investigate the hypotheses advanced by Roger Barker (1960) concerning the effects of undermanning on a behavioral setting. One hundred male undergraduate psychology students served as subjects. These were randomly assigned to one of twenty groups having five members each. Ten groups were manned and ten were undermanned. In all groups there was a deviant character. In half the groups one member left, creating the undermanned condition. Data were collected from two sources. Subject's performance on a group task of adding mixed fractions were scored and a questionnaire was filled out by the subjects at the end of the task. While results were in the direction predicted, there were no significant differences between groups under the two conditions. Analysis reveals that there was significant group variability within a condition. One hypothesis confirmed was the predicted increase in effort by the undermanned groups to maintain the setting and have performance comparable to the manned groups. The effects posited by Barker were observed to occur, however, results of this study were inconclusive and suggest the need for further study.