DP13316 Equitable Voting Rules
|Author(s):||Laurent Bartholdi, Wade Hann-Caruthers, Maya Josyula, Omer Tamuz, Leeat Yariv|
|Publication Date:||November 2018|
|Keyword(s):||equity, Finite Groups, May's Theorem, Social Choice, Voting rules|
|JEL(s):||C60, D71, D72|
|Programme Areas:||Public Economics, Industrial Organization|
|Link to this Page:||cepr.org/active/publications/discussion_papers/dp.php?dpno=13316|
A celebrated result in social choice is May's Theorem (May, 1952), providing the foundation for majority rule. May's crucial assumption of symmetry, often thought of as a procedural equity requirement, is violated by many choice procedures that grant voters identical roles. We show that a modification of May's symmetry assumption allows for a far richer set of rules that still treat voters equally, but have minimal winning coalitions comprising a vanishing fraction of the population. We conclude that procedural fairness can coexist with the empowerment of a small minority of individuals. Methodologically, we introduce techniques from discrete mathematics and illustrate their usefulness for the analysis of social choice questions.