• Corpus ID: 3131335

Llull and Copeland Voting Computationally Resist Bribery and Control

@article{Faliszewski2008LlullAC,
  title={Llull and Copeland Voting Computationally Resist Bribery and Control},
  author={Piotr Faliszewski and Edith Hemaspaandra and Lane A. Hemaspaandra and J{\"o}rg Rothe},
  journal={ArXiv},
  year={2008},
  volume={abs/0809.4484}
}
The only systems previously known to be resistant to all the standard control types were highly artificial election systems created by hybridization. We study a parameterized version of Copeland voting, denoted by Copeland^\alpha, where the parameter \alpha is a rational number between 0 and 1 that specifies how ties are valued in the pairwise comparisons of candidates. We prove that Copeland^{0.5}, the system commonly referred to as "Copeland voting," provides full resistance to constructive… 

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References

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Copeland Voting Fully Resists Constructive Control
TLDR
It is proved that Copeland0.5, the system commonly referred to as "Copeland voting," provides full resistance to constructive control, among systems with a polynomial-time winner problem, this is the first natural election system proven to have full resistanceto constructive control.
Llull and Copeland Voting Broadly Resist Bribery and Control
TLDR
This paper proves that an election system developed by the 13th century mystic Ramon Llull and the well-studied Copeland election system are both resistant to all the standard types of (constructive) electoral control other than one variant of addition of candidates.
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