An \(\frac{8}{5}\)-Approximation Algorithm for a Hard Variant of Stable Marriage

  • Robert W. Irving
  • David F. Manlove
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4598)


When ties and incomplete preference lists are permitted in the Stable Marriage problem, stable matchings can have different sizes. The problem of finding a maximum cardinality stable matching in this context is known to be NP-hard, even under very severe restrictions on the number, size and position of ties. In this paper, we describe a polynomial-time \(\frac{8}{5}\)-approximation algorithm for a variant in which ties are on one side only and at the end of the preference lists. The particular variant is motivated by important applications in large scale centralized matching schemes.


Approximation Algorithm Stable Match Performance Guarantee Maximum Cardinality Acceptable Pair 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • Robert W. Irving
    • 1
  • David F. Manlove
    • 1
  1. 1.Department of Computing Science, University of Glasgow, Glasgow G12 8QQUK

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