# Who Has Dominant Strategy in Game Theory?

//

Vincent White

Game theory is a branch of mathematics that deals with decision-making in situations where multiple players are involved. It is widely used in various fields, including economics, political science, and psychology. One of the primary concepts of game theory is a dominant strategy, which refers to a strategy that always yields the best outcome for a player, regardless of the other players’ choices.

So, who has a dominant strategy in game theory? The answer to this question varies depending on the type of game being played. In some games, one player may have a dominant strategy, while in others, no player may have a dominant strategy.

Let us consider an example to understand this concept better. Suppose two players are playing the game of ‘Prisoner’s Dilemma.’

In this game, both players have two options: cooperate or defect. The payoff matrix for this game is as follows:

– If both players cooperate (C,C), they each receive a payoff of 3.
– If both players defect (D,D), they each receive a payoff of 1.
– If one player cooperates and the other defects (C,D or D,C), the cooperating player receives a payoff of 0 while the defecting player receives a payoff of 5.

In this game, if both players choose to cooperate, they will receive a payoff of 3 each. However, if one player chooses to defect while the other cooperates, the defecting player will receive a higher payoff of 5 while the cooperating player will receive nothing. Therefore, it may seem like choosing to defect is always better than cooperating.

However, if both players choose to defect, they will receive only a payoff of 1 each which is less than if they had both cooperated. Hence neither cooperation nor defection can be considered as absolute dominant strategies.

In some games like ‘Matching Pennies,’ no player has a dominant strategy. In this game, two players simultaneously show either a heads or tail on a penny. The payoff matrix for this game is as follows:

– If both players show the same side (H,H or T,T), player 1 wins.
– If both players show different sides (H,T or T,H), player 2 wins.

In this game, no matter what strategy either player chooses, the other player can always choose a strategy that will give them an equal chance of winning. Hence, there is no dominant strategy for either player.

To summarize, the presence of a dominant strategy in game theory depends on the specific game being played. The concept of a dominant strategy is essential in analyzing and understanding strategic decision-making in various fields.