Financial Networks

摘要

Networks are natural tools for understanding complex social and economic phenomena. Examples include technology diffusion, neighborhood effects, financial crises and contagion, social learning, and globalization. The surveys by Sanjeev Goyal (2005) and Matthew O. Jackson (2005) provide many examples. We can also think of markets as being structured like networks. The traditional Walrasian theory assumes that commodities are traded on a centralized exchange. The closest counterparts in the real world are stock exchanges such as the New York Stock Exchange (NYSE) or NASDAQ, or commodity exchanges such as the Chicago Board of Trade (CBOT). Decentralized trade, on the other hand, is naturally thought of as taking the form of a network. For example, the concept of a network can be used to model the market for interbank lending and to study the phenomenon of contagion.