Optimal Transport Networks in Spatial Equilibrium
研究空间均衡中的最优交通网络，构建包含劳动力流动的新古典贸易模型，分析交通拥堵和基础设施对运输成本的影响，并求解社会规划者的最优基础设施投资问题。
We study optimal transport networks in spatial equilibrium. We develop a framework consisting of a neoclassical trade model with labor mobility in which locations are arranged on a graph. Goods must be shipped through linked locations, and transport costs depend on congestion and on the infrastructure in each link, giving rise to an optimal transport problem in general equilibrium. The optimal transport network is the solution to a social planner's problem of building infrastructure in each link. We provide conditions such that this problem is globally convex, guaranteeing its numerical tractability. We also study cases with increasing returns to transport technologies in which global convexity fails. We apply the framework to assess optimal investments and inefficiencies in the road networks of European countries.