Individual and Collective Information Acquisition: An Experimental Study

Many committees—juries, political task forces, etc.—spend time gathering costly information before reaching a decision. We report results from lab experiments focused on such informationcollection processes. We consider decisions governed by individuals and groups and compare how voting rules affect outcomes. We also contrast static information collection, as in classical hypothesis testing, with dynamic collection, as in sequential hypothesis testing. Generally, outcomes approximate the theoretical benchmark and sequential information collection is welfare enhancing relative to static collection. Nonetheless, several important departures emerge. Static information collection is excessive, and sequential information collection is non-stationary, producing declining decision accuracies over time. Furthermore, groups using majority rule yield especially hasty and inaccurate decisions. We thank Roland Benabou, Stephen Morris, Salvo Nunnari, and Wolfgang Pesendorfer for very helpful discussions and feedback. We gratefully acknowledge the support of NSF grants SES-1629613 and SES-1949381. Department of Economics, Princeton University preshidi@princeton.edu Department of Economics, Princeton University lizzeri@princeton.edu Department of Economics, Princeton University lyariv@princeton.edu Department of Economics, The Chinese University of Hong Kong jimmyhingchan@cuhk.edu.hk Faculty of Business and Economics, University of Hong Kong wsuen@econ.hku.hk