American Economic Journal: Macroeconomics · 2019 · Esteban Rossi‐Hansberg、Pierre-Daniel G. Sarte、Felipe Schwartzman
中文摘要
在美国,与更高工资相关联的认知类非常规(CNR)职业在较大城市中的占比明显偏高。为研究劳动者在各城市间的配置,我们构建并量化了一个包含多个产业的空间均衡模型,这些产业雇用CNR职业及其他(非CNR)职业。生产率因城市—产业—职业而异,且部分由本地劳动者之间的外部性决定。我们估计,一个城市中CNR劳动者的生产率显著取决于该城市CNR劳动者所占份额与总就业规模。结合对区位的异质性偏好,这些外部性意味着均衡配置并非有效。一项使各职业劳动者同等受益的最优政策会激励认知中心的形成,使得当今一些最大城市中CNR劳动者占比更高。与此同时,这些城市规模缩小以缓解拥挤效应,而初始规模较小的城市规模则扩大。大城市与小城市最终会扩张其已经集中的产业,而中等规模城市则倾向于跨产业多元化。因此,最优配置的特征是向从大城市迁往小城市的非CNR劳动者进行转移支付,这与隐含的产业结构格局变化相一致。最后,我们表明最优政策强化了1980年以来所观察到的均衡趋势。然而,这些趋势部分源于CNR充裕城市中房地产生产率的低增长,后者降低了福利。
Abstract
In the U.S., cognitive non-routine (CNR) occupations associated with higher wages are disproportionately represented in larger cities.To study the allocation of workers across cities, we propose and quantify a spatial equilibrium model with multiple industries that employ CNR and alternative (non-CNR) occupations.Productivity is city-industry-occupation specific and partly determined by externalities across local workers.We estimate that the productivity of CNR workers in a city depends significantly on both its share of CNR workers and total employment.Together with heterogeneous preferences for locations, these externalities imply equilibrium allocations that are not efficient.An optimal policy that benefits workers equally across occupations incentivizes the formation of cognitive hubs, leading to larger fractions of CNR workers in some of today's largest cities.At the same time, these cities become smaller to mitigate congestion effects while cities that are initially small increase in size.Large and small cities end up expanding industries in which they already concentrate, while medium-size cities tend to diversify across industries.The optimal allocation thus features transfers to non-CNR workers who move from large to small cities consistent with the implied change in the industrial composition landscape.Finally, we show that the optimal policy reinforces equilibrium trends observed since 1980.However, these trends were in part driven by low growth in real-estate productivity in CNR-abundant cities that reduced welfare.