Standard equilibrium concepts in game theory find it difficult to explain the empirical evidence from a large number of static games, including the prisoner's dilemma game, the hawk-dove game, voting games, public goods games and oligopoly games. Under uncertainty about what others will do in one-shot games, evidence suggests that people often use evidential reasoning (ER), i.e., they assign diagnostic significance to their own actions in forming beliefs about the actions of other like-minded players. This is best viewed as a heuristic or bias relative to the standard approach. We provide a formal theoretical framework that incorporates ER into static games by proposing evidential games and the relevant solution concept: evidential equilibrium (EE). We derive the relation between a Nash equilibrium and an EE. We illustrate these concepts in the context of the prisoner's dilemma game.
evidential reasoning game theory cognitive bias prisoner's dilemma game oligopoly games conservative heuristics radical heuristics decision making