Ambiguity in Games: The Role of Uncertainty in Strategic Interactions

• Applicant: Professor Dr. Frank Riedel
• Subject Area: Economic Theory
• Term: from 2013 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 230418795

• Final Report Year: 2020

Final Report Abstract

The project looks at the issue of ambiguity, or non probabilistic uncertainty, in an interaction setting. It develops foundational aspects in decision theory and game theory, dealing in particular with the notion of dynamic consistency (of single decisions and of Ellsberg equilibria). It also provides applications of ambiguity to some particular strategic settings: certification of information, ambiguous communication and persuasion, contractual arrangements under moral hazard. Finally, issues of aggregation of ambiguous beliefs have also been given some answers. This project enhanced the Franco-German scientific collaboration in multiple ways: joint work, joint organization of conferences in Bielefeld and in Paris. At the end of the project, we decided to continue our collaboration; in the meantime, we have successfully formed a new group that also includes Queen Mary University, London, and Kyoto University, Kyoto. The new project “Ambiguity in Dynamic Environments” is also being funded by the Open Research Area in the Social Sciences.

Publications

• Harsanyi’s Aggregation Theorem with Incomplete Preferences, American Economic journal: Microeconomics, 7, 61–69, 2015
  Danan, E., B. Hill, T. Gajdos, J.M. Tallon
  
• Social Robust Decisions, American Economic Review, 106, 2407–25, 2016
  Danan, E., B. Hill, T. Gajdos, J.M. Tallon
  
• Solution concepts for games with ambiguous payoffs, Theory and Decision, 80, 245–269, 2016
  Beauchêne
  
• Flexible contracts, Games and Economic Behavior, 103, 145–167, 2017
  Gottardi, P. and J.M. Tallon
  
• Hard evidence and ambiguity aversion, Theory and Decision, 82, 327–339, 2017
  Ayouni, M. and F. Koessler
  
• Kuhn’s theorem for extensive form Ellsberg games, Journal of Mathematical Economics 68, 26–41, 2017
  Mouraviev, I., F. Riedel, L. Sass
  
• Dynamically Consistent Preferences Under Imprecise Probabilistic Information, Journal of Mathematical Economics 79, 117-124, 2018
  Riedel, F., J.M. Tallon and V. Vergopoulos
  
• Ambiguous persuasion, Journal of Economic Theory, 179, 312–365, 2019
  Beauchêne, D., Li, M. and Li, J.
  
• Purification and Disambiguation of Ellsberg Equilibria, Economic Theory, 69, 595–636, 2020
  Decerf, B and F. Riedel