Strategic manipulability without resoluteness or shared beliefs: Gibbard-Satterthwaite generalized

  title={Strategic manipulability without resoluteness or shared beliefs: Gibbard-Satterthwaite generalized},
  author={John Duggan and Thomas Schwartz},
  journal={Social Choice and Welfare},
Abstract. The Gibbard-Satterthwaite Theorem on the manipulability of social-choice rules assumes resoluteness: there are no ties, no multi-member choice sets. Generalizations based on a familiar lottery idea allow ties but assume perfectly shared probabilistic beliefs about their resolution. We prove a more straightforward generalization that assumes almost no limit on ties or beliefs about them. 
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