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Does moral play equilibrate?


  • Bomze, Immanuel
  • Schachinger, Werner
  • Weibull, Jorgen


Some finite and symmetric two-player games have no (pure or mixed) symmetric Nash equilibrium when played by partly morally motivated players. The reason is that the "right thing to do" may be not to randomize. We analyze this issue both under complete information between equally moral players and under incomplete information between arbitrarily moral players. We provide necessary and sufficient conditions for the existence of equilibrium and illustrate the results with examples and counter-examples.

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  • Bomze, Immanuel & Schachinger, Werner & Weibull, Jorgen, 2018. "Does moral play equilibrate?," MPRA Paper 89555, University Library of Munich, Germany.
  • Handle: RePEc:pra:mprapa:89555

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    References listed on IDEAS

    1. Benaïm, Michel & Hofbauer, Josef & Hopkins, Ed, 2009. "Learning in games with unstable equilibria," Journal of Economic Theory, Elsevier, vol. 144(4), pages 1694-1709, July.
    2. Ingela Alger & Jörgen W. Weibull, 2013. "Homo Moralis—Preference Evolution Under Incomplete Information and Assortative Matching," Econometrica, Econometric Society, vol. 81(6), pages 2269-2302, November.
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    More about this item


    Nash equilibrium; morality; homo moralis; social preferences; incomplete information;
    All these keywords.

    JEL classification:

    • C72 - Mathematical and Quantitative Methods - - Game Theory and Bargaining Theory - - - Noncooperative Games
    • D01 - Microeconomics - - General - - - Microeconomic Behavior: Underlying Principles
    • D64 - Microeconomics - - Welfare Economics - - - Altruism; Philanthropy; Intergenerational Transfers
    • D82 - Microeconomics - - Information, Knowledge, and Uncertainty - - - Asymmetric and Private Information; Mechanism Design
    • D91 - Microeconomics - - Micro-Based Behavioral Economics - - - Role and Effects of Psychological, Emotional, Social, and Cognitive Factors on Decision Making

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