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Social Choice and Welfare

, Volume 8, Issue 4, pp 341–354 | Cite as

Single transferable vote resists strategic voting

  • John J. BartholdiIII
  • James B. Orlin
Article

Abstract

We give evidence that Single Tranferable Vote (STV) is computationally resistant to manipulation: It is NP-complete to determine whether there exists a (possibly insincere) preference that will elect a favored candiate, even in an election for a single seat. Thus strategic voting under STV is qualitatively more difficult than under other commonly-used voting schemes. Furthermore, this resistance to manipulation is inherent to STV and does not depend on hopeful extraneous assumptions like the presumed difficulty of learning the preferences of the other voters. We also prove that it is NP-complete to recognize when an STV election violates monotonicity. This suggests that non-monotonicity in STV elections might be perceived as less threatening since it is in effect “hidden” and hard to exploit for strategic advantage.

Keywords

Vote Scheme Strategic Vote Strategic Advantage Single Transferable Vote Single Seat 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag 1991

Authors and Affiliations

  • John J. BartholdiIII
    • 1
  • James B. Orlin
    • 2
  1. 1.School of Industrial and Systems EngineeringGeorgia Institute of TechnologyAtlantaUSA
  2. 2.Sloan School of ManagementMassachusetts Institute of TechnologyCambridgeUSA

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