Communication, Advice and Beliefs in an Experimental Public Goods Game

We study the efficacy of horizontal versus vertical social learning processes in a public goods game. In one treatment, subjects about to play the game can make nonbinding common knowledge announcements about their intentions while, in another, subjects do not communicate directly with group members but receive common knowledge advice from the previous generation of players. A third treatment has subjects play with neither communication nor advice. We find that groups that engage in peer communication achieve much lower levels of contribution to the public good than do groups that receive advice. We attribute this finding in part to the fact that some subjects in the communication treatment opted to make no announcement during the communication phase of play.