Voting Rules, Manipulability and Social Homogeneity

• Published in: Public choice Vol. 116; no. 1/2; pp. 165 - 184
• Main Authors: Lepelley, Dominique, Valognes, Fabrice
• Format: Journal Article
• Language: English
• Published: Dordrecht Kluwer Academic Publishers 01.07.2003; Springer Nature B.V; Springer Verlag
• Subjects: Alternative voting; Coalitions; Economic models; Economic theory; Economics; Economics and Finance; Elections; Electoral systems; Electorate; Homogeneity; Homogenization; Humanities and Social Sciences; Investigations; Literature; Manipulation; Mathematical functions; Plurality voting; Political candidates; Preferences; Probabilistic modeling; Probability; Public choice; Rules; Social choice; Social structure; Studies; Voter behavior; Voters; Votes; Voting; Voting Behavior; Voting behaviour; Voting paradox; Voting rules manipulability; social homogeneity
• ISSN: 0048-5829; 1573-7101
• DOI: 10.1023/A:1024221816507

To what extent are some voting rules more vulnerable to strategic manipulation than others? In order to answer this question, representations are developed for the coalitional manipulability of eight voting rules under various assumptions concerning the likelihood that given voters' preference profiles are observed on three alternatives. Of particular interest is the impact that social homogeneity (defined as the tendency of voters' preference to be similar) has on the manipulability of voting rules. The results we obtain show that the hierarchy of the voting rules that results from our computations can crucially depend on the degree of social homogeneity. However, it turns out that, whatever the degree of homogeneity, the Hare method (or two-stage plurality) minimizes susceptibility to strategic manipulation by coalitions of voters in three-candidate elections.