Game theory was once hailed as a revolutionary interdisciplinary phenomenon bringing together psychology, mathematics, philosophy and an extensive mix of other academic areas. Eight Noble Prizes have been awarded to those who have progressed the discipline; but beyond the academic level, is game theory actually applicable in today's world?
Yes!
The classical example of game theory in the business world arises when analyzing an economic environment characterized by an oligopoly. Competitive firms are faced with a decision matrix similar to that of a Prisoner's Dilemma. Each firm has the option to accept the basic pricing structure agreed upon by the other companies or to introduce a lower price schedule. Despite that it is in the common interest to cooperate with the competitors, following a logical thought process causes the firms to default. As a result everyone is worse off. Although this is a fairly basic scenario, decision analysis has influenced the general business environment and is a prime factor in the use of compliance contracts.
Game theory has branched out to encompass many other business disciplines. From optimal marketing campaign strategies, to waging war decisions, ideal auction tactics and voting styles, game theory provides a hypothetical framework with material implications. For example, pharmaceutical companies consistently face decisions regarding whether to market a product immediately and gain a competitive edge over rival firms, or prolong the testing period of the drug; if a bankrupt company is being liquidated and its assets auctioned off, what is the ideal approach for the auction; what is the best way to structure proxy voting schedules? Since these decisions involve numerous parties, game theory provides the base for rational decision making.
Another important concept, zerosum games, also stemmed from the original ideas presented in game theory and the Nash Equilibrium. Essentially, any quantifiable gains by one party are equal to the losses of another party. Swaps, forwards, options and other financial instruments are often described as "zerosum" instruments, taking their roots from a concept that now seems distant. (For an in depth explanation about game theory, check out Game Theory: Beyond the Basics.)
This question was answered by Arthur Pinkasovitch.

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