The distortion of distributed voting

@article{FilosRatsikas2019TheDO,
  title={The distortion of distributed voting},
  author={Aris Filos-Ratsikas and Evi Micha and Alexandros A. Voudouris},
  journal={ArXiv},
  year={2019},
  volume={abs/1905.01882}
}
Voting can abstractly model any decision-making scenario and as such it has been extensively studied over the decades. Recently, the related literature has focused on quantifying the impact of utilizing only limited information in the voting process on the societal welfare for the outcome, by bounding the distortion of voting rules. Even though there has been significant progress towards this goal, all previous works have so far neglected the fact that in many scenarios (like presidential… Expand
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References

SHOWING 1-10 OF 31 REFERENCES
Approval-Based Elections and Distortion of Voting Rules
TLDR
This work defines acceptability-distortion for a number of rules, including Plurality, Borda, $k$-Approval, Veto, the Copeland's rule, Ranked Pairs, the Schulze's method, and STV, and compute the distortion of Approval Voting. Expand
Divide and Conquer: Using Geographic Manipulation to Win District-Based Elections
TLDR
It is shown that many parties are potentially able to make themselves victorious using district manipulation, and that the relevant variables here go beyond share of the vote; the form of geographic dispersion also plays a crucial role. Expand
Awareness of Voter Passion Greatly Improves the Distortion of Metric Social Choice
We develop new voting mechanisms for the case when voters and candidates are located in an arbitrary unknown metric space, and the goal is to choose a candidate minimizing social cost: the totalExpand
Voting almost maximizes social welfare despite limited communication
TLDR
The notion of embeddings into voting rules: functions that receive an agent's utility function and return the agent's vote are presented and it is established that very low distortion can be obtained using randomizedembeddings, especially when the number of agents is large compared to thenumber of alternatives. Expand
Truthful and Near-Optimal Mechanisms for Welfare Maximization in Multi-Winner Elections
TLDR
The utilitarian social welfare of mechanisms for preference aggregation, measured by the distortion, is considered and it is shown that for a particular input format called threshold approval voting, there is a mechanism with nearly optimal distortion when the number of voters is large. Expand
The Distortion of Cardinal Preferences in Voting
TLDR
It is argued that, whenever voting is applied in a multiagent system, distortion must be a pivotal consideration. Expand
Misrepresentation in District Voting
TLDR
The Misrepresentation Ratio is defined which quantifies the deviation from proportional representation in a district-based election, and bounds for this ratio under various voting rules are provided. Expand
Improved Metric Distortion for Deterministic Social Choice Rules
TLDR
This paper designs an ordinal social choice rule with minimum distortion, which is the worst-case ratio, over all consistent metrics, between the social cost of the rule and that of the optimal omniscient rule with knowledge of the underlying metric space, and proposes a new voting rule via an alternative generalization of uncovered sets. Expand
More Natural Models of Electoral Control by Partition
TLDR
It is the hope that having these new partition types will allow studies of control attacks to include such models that more realistically capture many settings, and for some important cases analyze the complexity of these models. Expand
Relating Metric Distortion and Fairness of Social Choice Rules
TLDR
It is proved that the distinct notions of distortion and fairness ratio are in fact closely linked -- within an additive factor of 2 for any voting rule -- and thus STV also achieves an $O(\log m)$ fairness ratio. Expand
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