Incomplete Preferences in Single-Peaked Electorates

Abstract

Incomplete preferences are likely to arise in real-world preference aggregation scenarios. This paper deals with determining whether an incomplete preference profile is single-peaked. This is valuable information since many intractable voting problems become tractable given singlepeaked preferences. We prove that the problem of recognizing single-peakedness is NP-complete for incomplete profiles consisting of partial orders. Despite this intractability result, we find several polynomial-time algorithms for reasonably restricted settings. In particular, we give polynomial-time recognition algorithms for weak orders, which can be viewed as preferences with indifference.

Cite

Text

Fitzsimmons and Lackner. "Incomplete Preferences in Single-Peaked Electorates." Journal of Artificial Intelligence Research, 2020. doi:10.1613/JAIR.1.11577

Markdown

[Fitzsimmons and Lackner. "Incomplete Preferences in Single-Peaked Electorates." Journal of Artificial Intelligence Research, 2020.](https://mlanthology.org/jair/2020/fitzsimmons2020jair-incomplete/) doi:10.1613/JAIR.1.11577

BibTeX

@article{fitzsimmons2020jair-incomplete,
  title     = {{Incomplete Preferences in Single-Peaked Electorates}},
  author    = {Fitzsimmons, Zack and Lackner, Martin},
  journal   = {Journal of Artificial Intelligence Research},
  year      = {2020},
  pages     = {797-833},
  doi       = {10.1613/JAIR.1.11577},
  volume    = {67},
  url       = {https://mlanthology.org/jair/2020/fitzsimmons2020jair-incomplete/}
}