Regional Growth and Structural Change

城市经济学和经济地理学文献面临的一个关键挑战是为以下经验观察提供一致的理论解释：一方面，大多数国家的城市规模分布随着时间的推移保持了显著的稳定，而另一方面，在各自的城市层级中，单个城市具有很强的流动性，在国家和地方层面上存在大量的产业搅动和结构变化。重要的理论方法，如克鲁格曼（1991 JPE）开创的新经济地理学或亨德森（1974 AER）的经典城市系统模型，都从集聚和分散力量之间的基本权衡来解释经济的空间结构。这种权衡部分发生在部门内部，部分发生在部门之间，而聚集和分散力量的相对强度取决于跨空间运输货物、人员和思想的交易成本的大小。最近，有新的文献强调了外部贸易自由化和供给侧和需求侧诱导的结构变化对空间平衡结构的影响。然而，现有的理论大多是单独处理上述经验趋势，而没有明确说明它们的相互关系和相互作用。该项目的主要目的是为我们对区域增长和产业变革过程的理解提供重大贡献。我们计划开发一个理论框架，结合并扩展最近两种最有前途的方法，即Duranton （2007 AER）和Rossi-Hansberg/Wright （2007 RES）。这些模型还不能很好地解释上述实证趋势，因为(i)它们暗示了高度不现实的地方专业化模式，（ii）它们从国家层面的产业变化中抽象出来，（iii）它们假设了贸易和流动成本。在这个项目中，我们计划通过考虑现实的部门不对称和各种空间交易成本等因素，扩展并统一这两种模型。我们的目标是建立一个理论框架，使我们能够理解城市规模分布的长期稳定性如何与国家和地方层面的强劲工业搅动和结构变化相协调。这一新的理论框架将在成熟的一般均衡背景下应用于研究空间交易成本对这些过程的影响。结合这一主要目标，我们还计划揭示有关经济政策在区域增长和产业变革过程中的作用的重要见解。例如，这包括对区域政策和管辖权竞争的一般均衡机制的详细分析。

A key challenge for the literature in urban economics and economic geography is to provide a consistent theoretical explanation for the empirical observation that, on the one hand, city size distributions in most countries have remained remarkably stable over time, while on the other hand, there has been strong mobility of single cities within the respective urban hierarchy and substantial industry churning and structural change at the national and the local level.Important theoretical approaches, such as the new economic geography pioneered by Krugman (1991 JPE) or the classical urban systems models by Henderson (1974 AER), have explained the spatial structure of an economy from the fundamental trade-off between agglomeration and dispersion forces. This trade-off arises partly within, partly across sectors, and the relative strength of agglomeration and dispersion forces depends on the magnitude of transactions costs for moving goods, people and ideas across space. More recently, a new literature has emphasized the impacts of external trade liberalization and supply- and demand-side induced structural change on the spatial equilibrium structure. The existing theories address the aforementioned empirical trends mostly separately, however, without making explicit their interrelations and interactions.The main aim of this project is to provide significant contributions to our understanding about the processes of regional growth and industrial change. We plan to develop a theoretical framework that combines and extends the two most promising recent approaches, namely Duranton (2007 AER) and Rossi-Hansberg/Wright (2007 RES). Those models are not yet readily suited to explain the empirical trends described above, because (i) they imply highly unrealistic local specialization patterns, (ii) they abstract from industrial change at the national level, and (iii) they assume away trade and mobility costs.In this project we plan to extend and to unify these two models, by allowing for realistic sectoral asymmetries and for various spatial transaction costs, among other things. Our goal is to develop a theoretical framework that allows us to understand how the long-run stability of the city size distribution can be reconciled with strong industrial churning and structural change at the national and the local level. This new theoretical framework shall then be applied to study the impact of spatial transaction costs on these processes in a full-fledged general equilibrium context.In combination with this main goal, we also plan to uncover important insights about the role of economic policy for the processes of regional growth and industrial change. This includes, for example, a detailed analysis of the general equilibrium mechanisms of regional policy and of jurisdictional competition.