Growth and Indeterminancy in Dynamic Models with Externalities
研究无限期资本积累模型中技术外部性导致的均衡不确定性，发现单部门经济中均衡局部唯一，而两部门经济中正外部效应可能产生多维均衡流形，甚至引发增长率的持续波动。
We study the indeterminacy of equilibria in infinite horizon capital accumulation models with technological externalities. Our investigation encompasses models with bounded and unbounded accumulation paths, and models with one and two sectors of production. Under reasonable assumptions we find that equilibria are locally unique in one-sector economies. In economies with two sectors of production it is instead easy to construct examples where a positive external effect induces a two-dimensional manifold of equilibria converging to the same steady state (in the bounded case) or to the same constant growth rate (in the unbounded case). For the latter we point out that the dynamic behavior of these equilibria is quite complicated and that persistent fluctuations in their growth rates are possible.