The Power of Two Prices: Beyond Cross-Monotonicity

  • Yvonne Bleischwitz
  • Burkhard Monien
  • Florian Schoppmann
  • Karsten Tiemann
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4708)


Assuming strict consumer sovereignty (CS*), when can cost-sharing mechanisms simultaneously be group-strategyproof (GSP) and β-budget-balanced (β-BB)? Moulin mechanisms are GSP and 1-BB for submodular costs. We overcome the submodularity requirement and instead consider arbitrary—yet symmetric—costs:

  • Already for 4 players, we show that symmetry of costs is not sufficient for the existence of a GSP and 1-BB mechanism. However, for only 3 players, we give a GSP and 1-BB mechanism.

  • We introduce two-price cost-sharing forms (2P-CSFs) that define players’ cost shares and present a novel mechanism that is GSP given any such 2P-CSF. For subadditive costs, we give an algorithm to compute 2P-CSFs that are \({\ensuremath{\frac{\sqrt{17} + 1}{4}}}\)-BB (≈ 1.28). This result is then shown to be tight for 2P-CSFs. Yet, this is a significant improvement over 2-BB, which is the best Moulin mechanisms can achieve.

  • We give applications to the minimum makespan scheduling problem.

A key feature of all our mechanisms is a preference order on the set of players. Higher cost shares are always payed by least preferred players.


Cost Share Identical Machine Computing Center True Valuation Consumer Sovereignty 
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 2007

Authors and Affiliations

  • Yvonne Bleischwitz
    • 1
    • 2
  • Burkhard Monien
    • 1
  • Florian Schoppmann
    • 1
    • 2
  • Karsten Tiemann
    • 1
    • 2
  1. 1.Faculty of Computer Science, Electrical Engineering and Mathematics, University of Paderborn, Fürstenallee 11, 33102 PaderbornGermany
  2. 2.International Graduate School of Dynamic Intelligent Systems 

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