Restricting information exchange in dyads: can less discussion really be more helpful?

Research has shown that group members have a tendency to discuss a greater proportion of information that they have in common than information they do not. To make matters worse, group members are also more influenced by this common information than unique information. These biases can lead to groups making decisions without fully considering all relevant information. Previous research has suggested that imposing a restriction on the amount of information that can be exchanged may encourage members to make better use of unique information. To test this, I conducted a study in which participants received and exchanged information regarding two choices with a (computer simulated) partner before individually deciding on the best alternative. Half of the participants were restricted to 6 rounds of exchange (allowing exchange of about half of the information they possessed), while the others were allowed to exchange all information they possessed. The simulated partner either provided 4 pieces of information the participant had already seen and 2 the participant had not ("mostly common" condition) or 2 pieces the participant had seen and 4 the participant had not ("mostly unique" condition). After the decision, participants rated themselves and their partners in terms of task knowledge and task competence, as well as the items of information. Results found that participants significantly rated themselves higher than their partners, regardless of condition. Results also found that participants rated common information from their partners as more important than unique information, especially within the unique conditions. Implications of these findings are discussed.