Game theory
Traditional game theory uses theoretical models to determine the most beneficial choice of all players in a game. Game theory uses rational choice theory along with assumptions of players' common knowledge in order to predict utility-maximizing decisions. It also allows for players to predict their opponents' strategies. Traditional game theory is a primarily normative theory as it seeks to pinpoint the decision rational players should choose, but does not attempt to explain why that decision was made. Rationality is a primary assumption of game theory, so there are not explanations for different forms of rational decisions or irrational decisions.