Nash equilibrium

Solution concept of a non-cooperative game

In game theory, a Nash equilibrium is a situation where no player could gain more by changing their own strategy (holding all other players' strategies fixed) in a game. A Nash equilibrium is the most commonly used solution concept for non-cooperative games. If each player has chosen a strategy — an action plan based on what has happened so far in the game — and no individual player can increase their own expected payoff by changing their strategy while the other players keep theirs unchanged, then the current set of strategy choices constitutes a Nash equilibrium.

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