Evolution of Consistent Conjectures in Semi-aggregative Representation of Games, with Applications to Public Good Games and Contests

  • Alex PossajennikovEmail author


In a semi-aggregative representation of a game, the payoff of a player depends on a player’s own strategy and on a personalized aggregate of all players’ strategies. Suppose that each player has a conjecture about the reaction of the personalized aggregate to a change in the player’s own strategy. The players play an equilibrium given their conjectures, and evolution selects conjectures that lead to a higher payoff in such an equilibrium. Considering one player role, I show that for any conjectures of the other players, only conjectures that are consistent can be evolutionarily stable, where consistency means that the conjecture is, to a first approximation, correct at equilibrium. I illustrate this result in public good games and contests.


Evolutionary Stability Public Good Game Interior Equilibrium Pure Public Good Strict Nash Equilibrium 
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.



I would like to thank Dirk Rübbelke and Wolfgang Buchholz for this opportunity. I would also like to thank Alex Dickson for inviting me to participate in April 2011 in a workshop on aggregative games, which incited me to think about conjectures and aggregative games, and develop the ideas leading to this paper. I also thank Maria Montero for improving the exposition in the paper.


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© Springer International Publishing AG 2017

Authors and Affiliations

  1. 1.School of EconomicsUniversity of NottinghamNottinghamUK

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