Information processing in groups has long been seen as a cooperative process. In contrast with this assumption, group members were rarely found to behave cooperatively: They withhold unshared information and stick to initial incorrect decisions. In the present article, we examined how group...

We hypothesized that individual grading in group work, a widespread practice, hampers information sharing in cooperative problem solving. Experiment 1 showed that a condition in which members’ individual contribution was expected to be visible and graded, as in most graded work, led to less...