Are more heads more motivated than one? The role of communication in group belief updating

Many decisions are made by groups under uncertainty, with beliefs playing a critical role. However, less is known about how groups, often driven by self-serving motivations, aggregate these beliefs. In an experiment, we examine how groups form and update beliefs following communication and compare these to individual beliefs. We find that beliefs do not differ initially, however, group deliberation facilitates more motivated updating as groups become more pessimistic and less accurate than individuals over time. Text analyses reveal that groups with stronger self-serving motives send a larger volume of messages and are less likely to be anchored by initial proposals.