Who follows the crowd—Groups or individuals?

In games of social learning individuals tend to give too much weight to their own private information relative to the information that is conveyed by the choices of others (Weizsäcker, 2010). In this paper we investigate differences between individuals and small groups as decision makers in information cascade situations. In line with results from social psychology as well as results on Bayesian decision making (Charness et al., 2006) we find that groups behave more rationally than individuals. Groups, in particular, are able to abandon their own private signals more often than individuals when it is rational to do so. Our results indicate that the intellective part of the decision task contributes slightly more to the superior performance of groups than the judgmental part. Our findings have potential implications for the design of decision making processes in organisations, finance and other economic settings.

► We investigate experimentally decisions in information cascade situations.
► We examine differences between individuals and small groups as decision makers.
► We find that groups behave more rationally than individuals.
► Groups perform better in intellective tasks and judgmental tasks.
► The intellective part explains slightly more of the superior performance of groups.