GlossaryBayesian game: an interactive decision problem consisting of a set of n players, a set of types for every player, a probability distribution which accounts for the players' beliefs over each others' types, a set of actions for every player and a von Neumann-Morgenstern utility function de…ned over n-tuples of types and actions for every player.Nash equilibrium: in an n-person strategic form game, a strategy n-tuple from which unilateral deviations are not pro…table.von Neumann-Morgenstern utility function: a utility function which re ‡ects the individual's preferences over lotteries. Such a utility function is de…ned over outcomes and can be extended to any lottery by taking expectation with respect to . 1 Pure strategy (or simply strategy): a mapping which, in an interactive decision problem, associates an action with the information of a player whenever this player can make a choice.Sequential equilibrium: a re…nement of the Nash equilibrium for n-person multistage interactive decision problems, which can be loosely de…ned as a strategy n-tuple together with beliefs over past information for every player, such that every player maximizes his expected utility given his beliefs and the others' strategies, with the additional condition that the beliefs satisfy (possibly sophisticated) Bayes updating given the strategies.Strategic (or normal) form game: an interactive decision problem consisting of a set of n players, a set of strategies for every player and a (typically, von Neumann-Morgenstern) utility function de…ned over n-tuples of strategies for every player.Utility function: a real valued mapping over a set of outcomes which re‡ects the preferences of an individual by associating a utility level ( a "payo¤") with every outcome.