Dynamic Models of Search and Learning

SBR-9422988 Lones Smith 在大多数市场中，买卖双方并不在某个中心地点见面，而是必须不断地寻找对方。 经济学家在分析市场结果时通常忽略搜索过程，而只是简单地假设在均衡中市场出清价格是常识。 达到均衡和均衡价格成为常识的过程被视为“黑箱”。“该研究项目的第一部分打开了这个黑匣子，以进行更仔细的审查。 私家侦探研究了整个就业匹配模型，并提供了一个连贯的理论基础上的有效和均衡的结果时，个人本质上是不同的。 30年前，乔治斯蒂格勒教授提出，寡头垄断是不稳定的，并提出了一个“秘密”降价的过程，这似乎会导致任何寡头垄断协议朝着竞争的结果瓦解。 然而，尽管有许多努力，隐式博弈仍然没有解决，所以施蒂格勒的约束均衡仍然是一个猜想。 这一领域的所有最新进展都是在施蒂格勒博弈的数量设定版本上，在这个版本中，价格是可观察的，产量是不可观察的。 这样的游戏有一个递归的结构，动态规划可以成功地应用。 这个研究项目的第二部分是试图解决原来的更困难的Stigler定价游戏。这是间接地通过检查一个未解决的问题，从搜索文献被称为Renaissance问题。 这个问题有很多相同的正式结构斯蒂格勒的寡头垄断游戏，即它是一个重复的游戏，不完善的监测和私人观察到的信号，但似乎更容易处理。

SBR-9422988 Lones Smith In most markets buyers and sellers do not meet at some central site, but must constantly seek each other out. Economists usually ignore the search process when analyzing market outcomes and simply assume that in equilibrium the market-clearing price is common knowledge. The process by which equilibrium is attained and the equilibrium price becomes common knowledge is treated as a "black box." The first part of this research project opens up this black box to more careful scrutiny. The P.I. investigates the whole class of employment matching models and provides a coherent theory underlying the efficient and equilibrium outcomes when individuals are inherently different. Thirty years ago, Professor George Stigler suggested that oligopolies were unstable and proposed a process of "secret" price cuts that would seem to cause any oligopoly agreement to unravel toward the competitive outcome. Yet despite many efforts the implicit game remains unsolved and so Stigler's conjectured equilibrium remains a conjecture. All the recent progress in this area has been on the quantity-setting version of Stigler's game in which prices were observable and output unobservable. Such games have a recursive structure to which dynamic programming can be successfully applied. The second part of this research project is an attempt to solve the original much harder Stigler pricing game. This is done indirectly by examining an unsolved problem from the search literature known as the Rendezvous problem. This problem has much of the same formal structure as Stigler's oligopoly game, namely it is a repeated game with imperfect monitoring and privately observed signals, yet appears to be more tractable.