Condorcet winning sets

Journal article

An alternative is said to be a Condorcet winner of an election if it is preferred to any other alternative by a majority of voters. While this is a very attractive solution concept, many elections do not have a Condorcet winner. In this paper, we propose a set-valued relaxation of this concept, which we call a Condorcet winning set: such sets consist of alternatives that collectively dominate any other alternative. We also consider a more general version of this concept, where instead of domination by a majority of voters we require domination by a given fraction (Formula presented.) of voters; we refer to such sets as (Formula presented.)-winning sets. We explore social choice-theoretic and algorithmic aspects of these solution concepts, both theoretically and empirically.

Authors: Elkind, E; Lang, J; Saffidine, A

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Springer-Verlag
• Journal: Social Choice and Welfare
• Volume: 44
• Issue: 3
• Pages: 493-517
• Publication date: 2015-03-01
• DOI: 10.1007/s00355-014-0853-4
• ISSN: 0176-1714