Are Sunspots Necessary?
在一个简单的两岛屿世代交叠模型中，证明了存在所有不确定性均为内生的平稳理性预期均衡，通过构造各岛屿的太阳黑子均衡并利用定价方程消除太阳黑子变量，得到非平凡随机均衡。
In this paper, the author shows the existence of stationary rational expectations equilibria in a simple, two-island, overlapping-generations model of the type first considered by Robert E. Lucas, Jr., in which all uncertainty is endogenous. The result is obtained by first constructing "sunspot" equilibria on each island separately and then using the equilibrium pricing equations to eliminate the sunspot variable. In the resulting equilibrium, each island's prices serve as the sunspot for the other island. The constructed equilibrium is nontrivially stochastic. Copyright 1989 by University of Chicago Press.