Asymmetric Information

In economics and contract theory, an information asymmetry is present when one party to a transaction has more or better information than the other party. (This is also called a state of asymmetric information). Most commonly, information asymmetries are studied in the context of principal-agent problems. In 2001, the Bank of Sweden Prize in Economic Sciences in Memory of Alfred Nobel was awarded to George Akerlof, Michael Spence, and Joseph E. Stiglitz "for their analyses of markets with asymmetric information."
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Information that is known to some people but not to other people.