Pareto Optimal Matchings in Many-to-Many Markets with Ties

  • Katarína Cechlárová
  • Pavlos Eirinakis
  • Tamás Fleiner
  • Dimitrios Magos
  • David F. Manlove
  • Ioannis Mourtos
  • Eva Oceľáková
  • Baharak RastegariEmail author
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9347)


We consider Pareto-optimal matchings (POMs) in a many-to-many market of applicants and courses where applicants have preferences, which may include ties, over individual courses and lexicographic preferences over sets of courses. Since this is the most general setting examined so far in the literature, our work unifies and generalizes several known results. Specifically, we characterize POMs and introduce the Generalized Serial Dictatorship Mechanism with Ties (GSDT) that effectively handles ties via properties of network flows. We show that GSDT can generate all POMs using different priority orderings over the applicants, but it satisfies truthfulness only for certain such orderings. This shortcoming is not specific to our mechanism; we show that any mechanism generating all POMs in our setting is prone to strategic manipulation. This is in contrast to the one-to-one case (with or without ties), for which truthful mechanisms generating all POMs do exist.


Pareto optimality Many-to-many matching Serial dictatorship Truthfulness 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  • Katarína Cechlárová
    • 1
  • Pavlos Eirinakis
    • 2
  • Tamás Fleiner
    • 3
  • Dimitrios Magos
    • 4
  • David F. Manlove
    • 5
  • Ioannis Mourtos
    • 2
  • Eva Oceľáková
    • 1
  • Baharak Rastegari
    • 5
    Email author
  1. 1.Institute of Mathematics, Faculty of ScienceP.J. S̆afárik UniversityKos̆iceSlovakia
  2. 2.Department of Management Science and TechnologyAthens University of Economics and BusinessAthensGreece
  3. 3.Department of Computer Science and Information TheoryBudapest University of Technology and Economics and MTA-ELTE Egerváry Research GroupBudapestHungary
  4. 4.Department of InformaticsTechnological Educational Institute of AthensEgaleoGreece
  5. 5.School of Computing ScienceUniversity of GlasgowGlasgowUK

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