Open AccessRobust mechanism design and dominant strategy voting rules
Author(s) -
Börgers Tilman,
Smith Doug
Publication year - 2014
Publication title -
theoretical economics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 4.404
H-Index - 32
eISSN - 1555-7561
pISSN - 1933-6837
DOI - 10.3982/te1111
Subject(s) - voting , pareto principle , anti plurality voting , interim , cardinal voting systems , computer science , bullet voting , social choice theory , mechanism design , mechanism (biology) , simple (philosophy) , mathematical economics , dictatorship , pareto efficiency , mathematical optimization , microeconomics , economics , mathematics , political science , politics , law , philosophy , epistemology , democracy
We develop an analysis of voting rules that is robust in the sense that we do not make any assumption regarding voters' knowledge about each other. In dominant strategy voting rules, voters' behavior can be predicted uniquely without making any such assumption. However, on full domains, the only dominant strategy voting rules are random dictatorships. We show that the designer of a voting rule can achieve Pareto improvements over random dictatorship by choosing rules in which voters' behavior can depend on their beliefs. The Pareto improvement is achieved for all possible beliefs. The mechanism that we use to demonstrate this result is simple and intuitive, and the Pareto improvement result extends to all equilibria of the mechanism that satisfy a mild refinement. We also show that the result only holds for voters' interim expected utilities, not for their ex post expected utilities.