Theory and Decision

, Volume 64, Issue 2–3, pp 333–362 | Cite as

Granny Versus Game Theorist: Ambiguity in Experimental Games

  • Jürgen Eichberger
  • David Kelsey
  • Burkhard C. SchipperEmail author


We report on an experiment in which subjects choose actions in strategic games with either strategic complements or substitutes against a granny, a game theorist or other subjects. The games are selected in order to test predictions on the comparative statics of equilibrium with respect to changes in strategic ambiguity. We find that subjects face higher ambiguity while playing against the granny than playing against the game theorist if we assume that subjects are ambiguity averse. Moreover, under the same assumption, subjects choose more secure actions in games more prone to ambiguity which is in line with the predictions.


Choquet expected utility equilibrium under ambiguity experiments Knightian uncertainty strategic uncertainty 

JEL Classifications

C70 C72 C90 C91 D80 D81 


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Copyright information

© Springer Science+Business Media LLC 2007

Authors and Affiliations

  • Jürgen Eichberger
    • 1
  • David Kelsey
    • 2
  • Burkhard C. Schipper
    • 3
    Email author
  1. 1.Wirtschaftstheorie IAlfred-Weber-Institut für WirtschaftswissenschaftenHeidelbergGermany
  2. 2.Department of Economics, School of Business and EconomicsUniversity of ExeterExeter, DevonEngland
  3. 3.Department of EconomicsUniversity of California, DavisDavisUSA

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