English

One-sided version of Gale-Shapley proposal algorithm and its likely behavior under random preferences

Combinatorics 2020-05-15 v1

Abstract

For a two-sided (nn men/nn women) stable matching problem) Gale and Shapley studied a proposal algorithm (men propose/women select, or the other way around), that determines a matching, not blocked by any unmatched pair. Irving used this algorithm as a first phase of his algorithm for one-sided (stable roommates) matching problem with nn agents. We analyze a fully extended version of Irving's proposal algorithm that runs all the way until either each agent holds a proposal or an agent gets rejected by everybody on the agent's preference list. It is shown that the terminal, directed, partnerships form a stable permutation with matched pairs remaining matched in any other stable permutation. A likely behavior of the proposal algorithm is studied under assumption that all nn rankings are independently uniform. It is proved that with high probability (w.h.p.) every agent has a partner, and that both the number of agents in cycles of length 3\ge 3 and the total number of stable matchings are bounded in probability. W.h.p. the total number of proposals is asymptotic to 0.5n3/20.5 n^{3/2}.

Keywords

Cite

@article{arxiv.2005.06691,
  title  = {One-sided version of Gale-Shapley proposal algorithm and its likely behavior under random preferences},
  author = {Boris Pittel},
  journal= {arXiv preprint arXiv:2005.06691},
  year   = {2020}
}
R2 v1 2026-06-23T15:32:02.680Z