Maximizing the benefits of diversity: Effects of group boundaries, time pressure, and task type on bias and group decision effectiveness

This study examined the effects of task type (whether or not there is a demonstrably correct solution), time pressure and the configuration of informational and demographic boundaries on bias and decision accuracy using a hidden profile task. Participants (n = 444) were assigned to 3-person groups containing members with medical or marketing roles that either converged with or crosscut gender lines, or worked in homogeneous gender groups. Each group had an “information outsider” whose facts were necessary to uncover the hidden profile and select the best decision alternative. This information outsider was also a gender outsider in convergent groups but was of the same gender of one member of the information pair in crosscut groups and shared gender with both members of the information pair in homogeneous gender groups. Based on the social categorization model, we hypothesized that groups with clear, strong subgroup boundaries (i.e., convergent groups) would have greater bias and poorer decision accuracy relative to groups with weaker subgroup boundaries (i.e., crosscut groups). Time pressure and task type were expected to further influence group boundaries and consequently affect decision accuracy and bias. Contrary to expectation, the configuration of informational and demographic boundaries, time pressure and task type did not affect bias and accuracy. Our findings suggest that crosscutting may not have been effective because gender boundaries were not strong enough to weaken informational boundaries. We did find a relationship, however, between members' pre-discussion preferences and group decision accuracy. Specifically, the greater the number of members entering discussion with the correct preference, the greater was the likelihood that the group would choose the best option. This finding is supportive of the common knowledge effect that suggests information pooling does not play a significant role in group judgments. Rather, group discussion merely justifies members' individual preferences and these judgments, in turn, serve as the input into the group judgment.