We consider decision problems under complete ignorance and extend the minimax regret principle to situations where, after taking an action, the decision maker does not necessarily learn the state of the world. For example, if the decision maker only learns what the outcome is, then all she knows...

We argue in favor of a departure from the standard equilibrium approach in game theory in favor of the less ambitious goal of describing only the actual behavior of rational players. We investigate the notion of rationality in behavioral models of extensive-form games (allowing for imperfect...

We investigate the extension of backward-induction to von Neumann extensive games (where information sets have a synchronous structure) and provide an epistemic characterization of it. Extensions of the idea of backward-induction were proposed by Penta (2009) and later by Perea (2013), who also...

In a companion paper we introduced a general notion of perfect Bayesian equilibrium which can be applied to arbitrary extensive-form games. The essential ingredient of the proposed definition is the qualitative notion of AGM-consistency. In this paper we provide an epistemic foundation for...

We provide a general notion of perfect Bayesian equilibrium which can be applied to arbitrary extensive-form games and is intermediate between subgame-perfect equilibrium and sequential equilibrium. The essential ingredient of the proposed definition is the qualitative notion of AGM-consistency,...

This is the first draft of a chapter for the forthcoming Handbook of Epistemic Logic, edited by Hans van Ditmarsch, Joe Halpern, Wiebe van der Hoek and Barteld Kooi (College Publications). Contents: 1. Introduction 2. Epistemic Models of Strategic-Form Games 3. Semantic Analysis of Common Belief...

The analysis of rational play in dynamic games is usually done within a static framework that specifies a player's initial beliefs as well as his disposition to revise those beliefs conditional on hypothetical states of information. We suggest a simpler approach, where the rationality of a...

We discuss a number of conceptual issues that arise in attempting to capture, in dynamic games, the notion that there is "common understanding" among the players that they are all rational. -- Belief revision ; common belief ; counterfactual ; dynamic game ; model of a game ; rationality