False-Name Manipulation in Weighted Voting Games Is Hard for Probabilistic Polynomial Time

@inproceedings{Rey2014FalseNameMI,
  title={False-Name Manipulation in Weighted Voting Games Is Hard for Probabilistic Polynomial Time},
  author={Anja Rey and J{\"o}rg Rothe},
  booktitle={LATIN},
  year={2014}
}
False-name manipulation refers to the question of whether a player in a weighted voting game can increase her power by splitting into several players and distributing her weight among these false identities. Relatedly, the beneficial merging problem asks whether a coalition of players can increase their power in a weighted voting game by merging their weights. For the problems of whether merging or splitting players in weighted voting games is beneficial in terms of the Shapley-Shubik and the… 
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This paper investigates by how much a player can change his power, as measured by the Shapley-Shubik index or the Banzhaf index, by means of a false-name manipulation, i.e., splitting his weight among two or more identities.
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