DEFINITION of 'Decision Theory '
An interdisciplinary approach to determine how decisions are made given unknown variables and an uncertain decision environment framework. Decision theory bring together psychology, statistics, philosophy and mathematics to analyze the decisionmaking process. Decision theory is applied to a wide variety of areas such as game theory, auctions, evolution and marketing.
INVESTOPEDIA EXPLAINS 'Decision Theory '
A common example of decision theory stems from the prisoner's dilemma in which two individuals are faced with an uncertain decision where the final outcome is not only based on their personal decision, but also on that of the other individual. Since both parties do not know what actions the other person will take, this results in an uncertain decision framework.
While mathematics and statistical models determine what the optimal decision should be, psychology and philosophy introduce factors of human behaviors to suggest the most likely outcome.

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