Pseudonyms in Cost-Sharing Games

  • Paolo Penna
  • Florian Schoppmann
  • Riccardo Silvestri
  • Peter Widmayer
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5929)


This work initiates the study of cost-sharing mechanisms that, in addition to the usual incentive compatibility conditions, make it disadvantageous for the users to employ pseudonyms. We show that this is possible only if all serviced users pay the same price, which implies that such mechanisms do not exist even for certain subadditive cost functions. In practice, a user can increase her utility by lying in one way (misreport her willingness to pay) or another (misreport her identity). We prove also results for approximately budget-balanced mechanisms. Finally, we consider mechanisms that rely on some kind of “reputation” associated to the pseudonyms and show that they are provably better.


Cost Sharing Combinatorial Auction Consumer Sovereignty Ramsey Theorem Versus Aluations 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2009

Authors and Affiliations

  • Paolo Penna
    • 1
  • Florian Schoppmann
    • 2
  • Riccardo Silvestri
    • 3
  • Peter Widmayer
    • 4
  1. 1.Dipartimento di Informatica ed ApplicazioniUniversità di SalernoBaronissiItaly
  2. 2.Department of Computer ScienceStanford UniversityStanfordUSA
  3. 3.Dipartimento di InformaticaUniversità di Roma “La Sapienza”RomaItaly
  4. 4.Institut für Theoretische InformatikETH ZürichZürichSwitzerland

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