Swap Bribery

  • Edith Elkind
  • Piotr Faliszewski
  • Arkadii Slinko
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5814)


In voting theory, bribery is a form of manipulative behavior in which an external actor (the briber) offers to pay the voters to change their votes in order to get her preferred candidate elected. We investigate a model of bribery where the price of each vote depends on the amount of change that the voter is asked to implement. Specifically, in our model the briber can change a voter’s preference list by paying for a sequence of swaps of consecutive candidates. Each swap may have a different price; the price of a bribery is the sum of the prices of all swaps that it involves. We prove complexity results for this model, which we call swap bribery, for a broad class of voting rules, including variants of approval and k-approval, Borda, Copeland, and maximin.


Preference Order Vote Rule Price Function Approval Vote Prefer Candidate 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2009

Authors and Affiliations

  • Edith Elkind
    • 1
    • 2
  • Piotr Faliszewski
    • 3
  • Arkadii Slinko
    • 4
  1. 1.School of ECSUniversity of SouthamptonUK
  2. 2.Division of Mathematical SciencesNanyang Technological UniversitySingapore
  3. 3.Dept. of Computer ScienceAGH Univ. of Science and TechnologyKrakówPoland
  4. 4.Dept. of MathematicsUniversity of AucklandNew Zealand

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