English

Finding Preference Profiles of Condorcet Dimension $k$ via SAT

Multiagent Systems 2016-03-03 v2 Artificial Intelligence Logic in Computer Science

Abstract

Condorcet winning sets are a set-valued generalization of the well-known concept of a Condorcet winner. As supersets of Condorcet winning sets are always Condorcet winning sets themselves, an interesting property of preference profiles is the size of the smallest Condorcet winning set they admit. This smallest size is called the Condorcet dimension of a preference profile. Since little is known about profiles that have a certain Condorcet dimension, we show in this paper how the problem of finding a preference profile that has a given Condorcet dimension can be encoded as a satisfiability problem and solved by a SAT solver. Initial results include a minimal example of a preference profile of Condorcet dimension 3, improving previously known examples both in terms of the number of agents as well as alternatives. Due to the high complexity of such problems it remains open whether a preference profile of Condorcet dimension 4 exists.

Keywords

Cite

@article{arxiv.1402.4303,
  title  = {Finding Preference Profiles of Condorcet Dimension $k$ via SAT},
  author = {Christian Geist},
  journal= {arXiv preprint arXiv:1402.4303},
  year   = {2016}
}

Comments

Corrected typos, updated references, and added conclusion