When is one head better than two? Interdependent information in group decision making

Abstract

Research on information exchange in group decision making has frequently assumed that information items have independent meanings. Relaxing this assumption raises new issues and presents new possibilities. In the experiment presented here, dyads worked on hidden profile decision tasks in which pairs of unshared information items had interdependent meanings. Dyad decisions were more likely to be accurate when each pair of interdependent items was allocated to a single member (a “connected” hidden profile) than when each pair of interdependent items was separated between the two members (a “disconnected” hidden profile). These information distributions influenced the degree to which dyads considered unshared information. Cognitive load was manipulated, and it impaired decision makers’ ability to identify connections among interdependent information items. The differentiated distribution of information inherent in transactive memory systems moderated the negative effects of cognitive load on dyad decisions.