TY - GEN
T1 - Manipulation of hamming-based approval voting for multiple referenda and committee elections
AU - Barrot, Nathanael
AU - Lang, Jérôme
AU - Yokoo, Makoto
N1 - Publisher Copyright:
© Copyright 2017, International Foundation for Autonomous Agents and Multiagent Systems (www.ifaamas.org). All Rights Reserved.
PY - 2017
Y1 - 2017
N2 - Several methods exist for electing committees of representatives and conducting multiple referenda based on approval voting. Recently, a family of rules for approval-based voting using ordered weighted averaging was proposed in [1], ranging from a simple candidate-wise majority (minisum) to egalitarian rule (minimax). Even though the first rule is strategyproof and the second is not, due to its egalitarian nature, only a partial study on manipulation has been conducted for inbetween rules. This paper investigates the maiiipulability of fair rules within this family. We first prove that all rules parameterized by fair (non-increasing) weight vectors are manipulable, except minisum, if we consider them either resolute with a tie-breaking mechanism or irresolute with classic extension principles. Then, we conduct an empirical study of the proportion of elections that are manipulable, showing that it increases based on the rule's fairness.
AB - Several methods exist for electing committees of representatives and conducting multiple referenda based on approval voting. Recently, a family of rules for approval-based voting using ordered weighted averaging was proposed in [1], ranging from a simple candidate-wise majority (minisum) to egalitarian rule (minimax). Even though the first rule is strategyproof and the second is not, due to its egalitarian nature, only a partial study on manipulation has been conducted for inbetween rules. This paper investigates the maiiipulability of fair rules within this family. We first prove that all rules parameterized by fair (non-increasing) weight vectors are manipulable, except minisum, if we consider them either resolute with a tie-breaking mechanism or irresolute with classic extension principles. Then, we conduct an empirical study of the proportion of elections that are manipulable, showing that it increases based on the rule's fairness.
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M3 - Conference contribution
AN - SCOPUS:85046489256
T3 - Proceedings of the International Joint Conference on Autonomous Agents and Multiagent Systems, AAMAS
SP - 597
EP - 605
BT - 16th International Conference on Autonomous Agents and Multiagent Systems, AAMAS 2017
A2 - Durfee, Edmund
A2 - Das, Sanmay
A2 - Larson, Kate
A2 - Winikoff, Michael
PB - International Foundation for Autonomous Agents and Multiagent Systems (IFAAMAS)
T2 - 16th International Conference on Autonomous Agents and Multiagent Systems, AAMAS 2017
Y2 - 8 May 2017 through 12 May 2017
ER -