Voting Systems and Strategic Manipulation: an Experimental Study

This paper presents experiments analyzing the strategic behavior of voters under three voting systems: plurality rule, approval voting, and the Borda count. Strategic behavior is significantly different under each treatment (voting system). Plurality rule leads voters to play in a more sophisticated manner, but not necessarily insincerely, displaying the lowest levels of manipulation. The opposite holds for the Borda count games, where players are the least sophisticated but the most insincere. Approval voting shows intermediate levels of strategic behavior. In terms of social efficiency, plurality rule unexpectedly performs better than both approval voting and the Borda count. Yet, plurality rule is the weakest performer under Condorcet efficiency, whereas approval voting and the Borda count perform remarkably well even with a small electorate.

The Effect of Identity, Incentives, and Information on Voting.

We report on majority voting experiments where subjects are randomly assigned identities in common with a candidate. However, subjects sometimes receive a financial incentive from voting contrary to their identity. We vary the size of the incentive as well as information voters have about the advantage of the incentive. We find that subjects are in.uenced by their assigned identities and the effect is stronger when voters have less information. Nevertheless, financial incentives reduce this influence. Our results suggest that identity may have an important affect on voter choices in elections where incentives and information are low. With Rebecca Morton and Kenneth C. Williams [This draft: 10/07]

An Experimental Study of Fair Division

I consider the problem of allocating a bundle of perfectly divisible goods through two different mechanisms proposed by Crawford (1979, 1980). The "Equal Division Divide and Choose" is a bargaining game where the divider, selected randomly, proposes a division and the chooser can either accept it or reject it. If it is accepted, the proposal is implemented, otherwise each player gets the "equal division". The other, called "Pareto Efficient Egalitarian Equivalent Allocation", introduces an extra stage in the game where the role of divider is auctioned off. I tested these two mechanisms in an experimental setting. The first mechanism gives results that are efficient and envy-free, but not equitable. Experimental data highlights interesting results about fairness when the two players enjoy asymmetric utilities. The second mechanism produces efficient, envy free, and equitable outcomes, even if players are not completely selfish and rational. This happens because of two reasons: the role of divider is not chosen by nature, but it is earned through a fair competition, and dividers pay the auction by transferring part of their payoffs to choosers. [This draft: 7/06]