Portioning Using Ordinal Preferences: Fairness and Efficiency

Abstract

A public divisible resource is to be divided among projects. We study rules that decide on a distribution of the budget when voters have ordinal preference rankings over projects. Examples of such portioning problems are participatory budgeting, time shares, and parliament elections. We introduce a family of rules for portioning, inspired by positional scoring rules. Rules in this family are given by a scoring vector (such as plurality or Borda) associating a positive value with each rank in a vote, and an aggregation function such as leximin or the Nash product. Our family contains well-studied rules, but most are new. We discuss computational and normative properties of our rules. We focus on fairness, and introduce the SD-core, a group fairness notion. Our Nash rules are in the SD-core, and the leximin rules satisfy individual fairness properties. Both are Pareto-efficient.

Cite

Text

Airiau et al. "Portioning Using Ordinal Preferences: Fairness and Efficiency." International Joint Conference on Artificial Intelligence, 2019. doi:10.24963/IJCAI.2019/2

Markdown

[Airiau et al. "Portioning Using Ordinal Preferences: Fairness and Efficiency." International Joint Conference on Artificial Intelligence, 2019.](https://mlanthology.org/ijcai/2019/airiau2019ijcai-portioning/) doi:10.24963/IJCAI.2019/2

BibTeX

@inproceedings{airiau2019ijcai-portioning,
  title     = {{Portioning Using Ordinal Preferences: Fairness and Efficiency}},
  author    = {Airiau, Stéphane and Aziz, Haris and Caragiannis, Ioannis and Kruger, Justin and Lang, Jérôme and Peters, Dominik},
  booktitle = {International Joint Conference on Artificial Intelligence},
  year      = {2019},
  pages     = {11-17},
  doi       = {10.24963/IJCAI.2019/2},
  url       = {https://mlanthology.org/ijcai/2019/airiau2019ijcai-portioning/}
}