Hierarchies of Conditional Beliefs and Interactive Epistemology in Dynamic Games

Abstract

The epistemic analysis of solution concepts for dynamic games involves statements about the players' beliefs conditional upon different histories of play, their conditional beliefs about each other's conditional beliefs, etc. To represent such statements, we construct a space of infinite (coherent) hierarchies of conditional probability systems, defined with respect to a fixed collection of relevant hypotheses concerning an external state (e.g., the strategy profile being played.) As an application, we derive results about common certainty of the opponent's rationality conditonal on an arbitrary collection of histories in multistage games with observed actions and (possibly) incomplete information.