The Proportional Veto Principle for Approval Ballots

Abstract

The proportional veto principle, which captures the idea that a candidate vetoed by a large group of voters should not be chosen, has been studied for ranked ballots in single-winner voting. We introduce a version of this principle for approval ballots, which we call flexible-voter representation (FVR). We show that while the approval voting rule and other natural scoring rules provide the optimal FVR guarantee only for some flexibility threshold, there exists a scoring rule that is FVR-optimal for all thresholds simultaneously. We also extend our results to multi-winner voting.

Cite

Text

Halpern et al. "The Proportional Veto Principle for Approval Ballots." International Joint Conference on Artificial Intelligence, 2025. doi:10.24963/IJCAI.2025/434

Markdown

[Halpern et al. "The Proportional Veto Principle for Approval Ballots." International Joint Conference on Artificial Intelligence, 2025.](https://mlanthology.org/ijcai/2025/halpern2025ijcai-proportional/) doi:10.24963/IJCAI.2025/434

BibTeX

@inproceedings{halpern2025ijcai-proportional,
  title     = {{The Proportional Veto Principle for Approval Ballots}},
  author    = {Halpern, Daniel and Procaccia, Ariel D. and Suksompong, Warut},
  booktitle = {International Joint Conference on Artificial Intelligence},
  year      = {2025},
  pages     = {3900-3907},
  doi       = {10.24963/IJCAI.2025/434},
  url       = {https://mlanthology.org/ijcai/2025/halpern2025ijcai-proportional/}
}