In (Bonanno, 2013), a solution concept for extensive-form games, called perfect Bayesian equilibrium (PBE), was introduced and shown to be a strict refinement of subgame-perfect equilibrium; it was also shown that, in turn, sequential equilibrium (SE) is a strict refinement of PBE. In (Bonanno,...

We argue in favor of a departure from the equilibrium approach in game theory towards the less ambitious goal of describing only the actual behavior of rational players. The notions of Nash equilibrium and its refinements require a specification of the players' choices and beliefs not only along...

In an earlier paper [Rational choice andAGMbelief revision, Artificial Intelligence, 2009] a correspondence was established between the choice structures of revealed-preference theory (developed in economics) and the syntactic belief revision functions of the AGM theory (developed in philosophy...

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 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 provide a new characterization of both belief update and belief revision in terms of a Kripke-Lewis semantics. We consider frames consisting of a set of states, a Kripke belief relation and a Lewis selection function. Adding a valuation to a frame yields a model. Given a model and a state, we...

Building on the analysis of Bonanno (2025) we introduce a simple modal logic containing three modal operators: a unimodal belief operator B, a bimodal conditional operator and the unimodal global operator □. For each AGM axiom for belief revision, we provide a corresponding modal axiom. The...

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...