A function defined on the set of situations in a game (cf. Games, theory of), the values of which are a numerical description of the utility of a player or of a team of players in a given situation.
The gain function is better known as the pay-off function.
Gain function. N.N. Vorob'ev (originator), Encyclopedia of Mathematics. URL: http://encyclopediaofmath.org/index.php?title=Gain_function&oldid=13744