Complexity of Manipulating and Controlling Approval-Based Multiwinner Voting

Yongjie Yang

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arXiv · 2302.11291

Complexity of Manipulating and Controlling Approval-Based Multiwinner Voting

Yongjie Yang

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Abstract

We investigate the complexity of several manipulation and control problems under numerous prevalent approval-based multiwinner voting rules. Particularly, the rules we study include approval voting (AV), satisfaction approval voting (SAV), net-satisfaction approval voting (NSAV), proportional approval voting (PAV), approval-based Chamberlin-Courant voting (ABCCV), minimax approval voting (MAV), etc. We show that these rules generally resist the strategic types scrutinized in the paper, with only a few exceptions. In addition, we also obtain many fixed-parameter tractability results for these problems with respect to several natural parameters, and derive polynomial-time algorithms for certain special cases.

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Yongjie Yang. 2023-02-22. Complexity of Manipulating and Controlling Approval-Based Multiwinner Voting. https://arxiv.org/abs/2302.11291

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