What Is Game Theory?
Last Updated on 28. April 2023 by Martin Schuster
Game theory is a toolbox with tools rather than a single theory. These tools help you to analyze situations, make decisions, and forecast decisions of other actors. A decision in game theory is a situation where your best decision depends on another player’s decision. At the same time, this player also takes our considerations into account when thinking about his options. As a consequence, our decisions are interdependent.
Game theory has four purposes:
- Advice on how to decide in a certain situation.
- Forecast, how someone will decide in a certain situation.
- Explain why someone made a decision.
- Design mechanisms to obtain the desired outcome.
In order to analyze situations, we need to simplify most situations. This means we cut off unimportant things. In the end, we have a model.
Closely related to game theory is the decision theory. There, we analyze situations where our decision doesn’t influence others decisions.
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In game theory, we make some important assumptions about the players.
- Perfect information: All players know the pay-offs of all other players in every decision constellation.
- The result (pay-off) depends on my decision and the decision of the other players.
- At the time of decision, no player can observe the decision of the other player. This could be modelled as simultaneous decisions.
- Players act rationally. A higher utility is valued more than a lower one.
- Utility can be displayed as a number.