Research
Research
Abstract: This paper investigates the effect of deliberation on collective decision-making when abstention is allowed. We present a model of majority-rule voting with common-interest and asymmetrically informed voters, varying the availability of communication. The addition of communication does not alter the set of equilibrium outcomes. Still, we hypothesize that communication decreases efficiency, based on the conjecture that messages from poorly informed voters dilute those from better-informed voters. Our experimental implementation of the model shows that communication actually improves the efficiency of collective decisions, primarily through an unanticipated mechanism: it curbs irrational voting by less-informed voters. Nevertheless, consistent with our message-dilution conjecture, efficiency is lower when everyone speaks than when only the better-informed do, because after communication less-informed voters rarely abstain and instead largely vote with the majority message.
Abstract: Free-riding incentives arise in committees when members acquire costly information and aggregate it through voting, as information is a public good. This study examines how pre-vote communication affects this problem. We present a model in which voters with common interests decide whether to purchase private information before voting, comparing institutions with and without an intermediate communication stage. The model predicts that when information is expensive, communication improves information acquisition, decision accuracy, and welfare; when information is inexpensive, communication diminishes these outcomes. We test the model’s main predictions in a laboratory experiment that varies information cost and the presence of communication. Experimental results forthcoming.