What is a Game?

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A game is a mathematical model of a strategic interaction, with the following elements:

  • Players: Games must have participants. Players can be people, busiensses, teams, political parties, countries, etc.

  • Choices: Players have to make a choice, or multiple choices between different actions. A strategy is a rule for choosing actions.

  • Outcomes: When the players are done choosing, an outcome occurs and the game ends. The outcome also must depend on the choices.

  • Preferences: Players have preferences over outcomes.

Two features are required to make a game strategic:

  1. Outcomes are determined by everyone’s actions
  2. Players have different preferences.

Games differ in a few aspects:

  1. Timing: Do players choose once? (Rps) Or over and over again? (Chess) Does the game eventually end? Does it continue forever? Do they choose simultaneously, or in turns?

  2. Observations: Can players observe each other’s choices?

  3. Uncertainty: Is the outcome rnadom, or is it a deterministic function of the player’s actions? Do some players have more or less information than others?

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