When Are Agents Negligible
研究有限代理人模型与连续代理人模型均衡截然不同的悖论，发现当行动观测存在噪声且噪声不随人数增加过快消失时，悖论消失，并给出耐用品垄断、公司收购和政府政策时间一致性等经济实例。
The authors examine the following paradox: in a dynamic setting, equilibria can be radically different in a model with a finite number of agents than in a model with a continuum of agents. They present a simple strategic setting in which this paradox is a general phenomenon. However, the paradox disappears when there is noisy observation of the players' actions and the aggregate level of noise does not disappear too rapidly as the number of players increases. The authors give several economic examples in which this paradox has recently received attention: durable-goods monopoly, corporate takeovers, and time consistency of optimal government policy. Copyright 1995 by American Economic Association.