Italian cameo bracelet representing the days of the week, corresponding to the planets as Roman gods: Diana as the Moon for Monday, Mars for Tuesday, Mercury for Wednesday, Jupiter for Thursday, Venus for Friday, Saturn for Saturday, and Apollo as the Sun for Sunday. Middle 19th century, Walters Art Museum.
Glossary of game theory terms. Constant Sum. In a constant sum game, the sum of all players' payoffs is the same for any outcome. Hence, a gain for one participant is always at the expense of another, such as in most sporting events. Given the conflicting interests, the equilibrium of such games is often in mixed strategies.
The mean of the sum of two random variables X and Y is the sum of their means: For example, suppose a casino offers one gambling game whose mean winnings are -$0.20 per play, and another game whose mean winnings are -$0.10 per play.