-size distribution? Do they affect individual city sizes? Do they contribute to the productivity advantage of large cities and the … toughness of competition in cities? The short answers are: no; yes; and it depends. -- trade frictions ; urban frictions ; city …-size distribution ; productivity ; markups …

productivity differences and internal trade frictions. We show that even in the absence of the typical externalities studied in the … relative to that chosen by a planner. In particular, optimal urbanization exceeds decentralized levels when productivity … closer to optimal policies than decentralized allocations whenever productivity differences in non-traded sectors are either …

-size distribution? Do they affect individual city sizes? Do they contribute to the productivity advantage of large cities and the … toughness of competition in cities? The short answers are: no; yes; and it depends. …

applied to investigate competition, agglomeration, spillover effects. The method offers to (i) have carry out estimations at …

We discuss the role of key regions in spatial development. Local productivity shocks can affect the entire economy as … particular, we identify the set of key regions with the highest potential to affect aggregate productivity, output, and welfare … congested so they can still attract additional labor in response to positive productivity shocks without local rents and input …

. -- Agglomeration ; increasing returns to scale ; imperfect competition …