Sunday 11 November 2012

Game Theory


 The game theory was first realized in 1928 when John von Neumann published his papers where he analysed the Brouwer’s fixed-point theorem of the possible outcome to the players of the zero-sum game when any of them cheats. Later Ockar Morgenstern joined him and together they published Theory of Games and Economic Behavior book. But first the main point in the theorem was that the player’s behaviour would be to cooperate, and based on it there were strategies developed. In the 1950th the Prisoners' Dilemma came onto the scene introduced by notable mathematicians Merrill M. Flood and Melvin Dresher. Around 1950, John Nash developed a criterion for mutual consistency of players' strategies, known as Nash equilibrium, applicable to a wider variety of games than the criterion proposed by von Neumann and Morgenstern. This equilibrium is sufficiently general to allow for the analysis of non-cooperative games in addition to cooperative ones. 1 The main ideas behind the game theory would be that this is always better to cooperate to produce mutually beneficial outcomes. However, each player is tempted to pursue his or her individual interests. Cooperation requires that both players compromise, and forego their individual maximum payoffs. Yet, in compromising, each player risks complete loss if the opponent decides to seek his or her own maximum payoff. Rather than risking total loss, players tend to prefer the less productive outcome. 2

The playoff matrix works like in the following video:


This is the shortest explanation why the matrix D would be preferred to the matrix A.


Though this is not always the best to cheat and really depends on possible outcome in each situation. If the possible earnings or loses are not significant fortunately many would prefer not to cheat. Now let’s look at where it is used.

Game theory has been used to study a wide variety of human and animal behaviors. It was initially developed in economics to understand a large collection of economic behaviors, including behaviors of firms, markets, and consumers. The use of game theory in the social sciences has expanded, and game theory has been applied to political, sociological, and psychological behaviors as well. In the politics the example is Cold War. During the Cold War the opposing alliances of NATO and the Warsaw Pact both had the choice to arm or disarm. From each side's point of view disarming while the opponent continues to arm would have led to military inferiority. If both sides chose to arm, neither could afford to attack each other, but at the high cost of maintaining and developing a nuclear arsenal. If both sides chose to disarm, war would be avoided and there would be no costs. If your opponent disarmed while you continue to arm, then you achieve superiority. Although the 'best' overall outcome is for both sides to disarm, the rational course for both sides is to arm. This is indeed what happened, and both sides poured enormous resources in to military research and armament for the next thirty years until the dissolution of the Soviet Union broke the deadlock.3

In environmental studies, the PD is evident in crises such as global climate change. It is argued all countries will benefit from a stable climate, but any single country is often hesitant to curb CO2 emissions. The immediate benefit to an individual country to maintain current behavior is perceived to be greater than the purported eventual benefit to all countries if behavior was changed, therefore explaining the current impasse concerning climate change.3

Now let’s look at the collusions and cartels. They have lots in common cartel is distinguished as formal agreement between competitors6 and collusion is an agreement between two or more persons, sometimes illegal and therefore secretive7. Though the collusions are prohibited in most countries there is evidence about cartels in between countries. The most recognized one is OPEK. As long as the members of cartel are following the agreement all of them are better off. But if any of the members tried to cheat the well-being of all members is falling down dramatically. In the single country market there are also some other constrains for the Prisoners Dilemma.The knowledge that the game will be played again leads players to consider the consequences of their actions; one's opponent may retaliate or be unwilling to cooperate in the future, if one's strategy always seeks maximum payoffs at the expense of the other player.2 This leads to collusive behaviour of the firms on the market in terms of keeping the promise. They do act in their best interests but do realise that it requires keeping in mind the interests of the other players and respecting them.  For the proof of this idea please watch the last two minutes of the following video:


Sources:

  1. http://en.wikipedia.org/wiki/Game_theory
  2. http://www.beyondintractability.org/bi-essay/prisoners-dilemma
  3. http://en.wikipedia.org/wiki/Prisoner's_dilemma
  4. http://connect.mcgraw-hill.com/connect/hmEBook.do?setTab=sectionTabs
  5. http://www.youtube.com
  6. http://en.wikipedia.org/wiki/Cartel
  7. http://en.wikipedia.org/wiki/Collusion

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