Large and productive metropolitan areas play a growing role in the working of developed and emerging economies alike. This paper surveys the recent contributions of urban economics, highlighting the role of external increasing returns—called agglomeration economies in the context of a city, which are key in the development and functioning of large, prosperous cities. One critical feature of these mechanisms is their cumulative nature: once set in motion, they feed themselves. The various costs associated with city size put a brake on such mechanisms. In many countries, the unevenness of the distribution of skilled labor across cities is both the cause and the consequence of particular agglomeration economies. Human capital is beneficial to the cities, which attract skills and talents. However, cities’ spatial concentration exacerbates regional disparities at the risk of generating strong political and social tensions within nations.

中文翻译：

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城市发展中的人力资本与集聚经济

大型生产性大都市地区在发达经济体和新兴经济体的工作中都发挥着越来越重要的作用。本文调查了城市经济学的最新贡献，着重指出了外部增加收益的作用-在城市背景下被称为集聚经济，这对大型繁荣城市的发展和功能至关重要。这些机制的一个关键特征是它们的累积性：一旦启动，它们就会自我养活。与城市规模有关的各种成本阻碍了这种机制。在许多国家，城市之间熟练劳动力分配的不均衡既是特定集聚经济的原因，也是其结果。人力资本对吸引技能和人才的城市有利。然而，