Measuring Violations of Positive Involvement in Voting

  title={Measuring Violations of Positive Involvement in Voting},
  author={W. Holliday and E. Pacuit},
In the context of computational social choice, we study voting methods that assign a set of winners to each profile of voter preferences. A voting method satisfies the property of positive involvement (PI) if for any election in which a candidate x would be among the winners, adding another voter to the election who ranks x first does not cause x to lose. Surprisingly, a number of standard voting methods violate this natural property. In this paper, we investigate different ways of measuring… 

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