城市规模、交流频率与人力资本外部性

City Size,Communication Frequency,and Human Capital Externalities

人力资本外部性是城市集聚经济的核心驱动力之一。本文使用微观企业数据评估城市的人力资本外部性强度,重点从交流频率视角检验了人力资本外部性的产生机制,并量化了其有效辐射距离。研究发现:(1)人力资本同时具有正向的溢出效应和负向的竞争效应,在创意型服务业(教育、科学研究、专业技术服务等)中溢出效应占据主导,在非创意型服务业(零售、餐饮、运输等)中竞争效应占据主导,人力资本外部性的大小和方向取决于这两种效应叠加后的结果。(2)大城市内人与人之间的交流互动是人力资本外部性产生的重要机制。(3)人力资本外部性的有效溢出距离十分有限,即使对于创意型服务业来说,人力资本外部性的有效溢出距离也仅为3km左右。

Human capital externality is one of the core drivers of urban agglomeration economies.This paper uses micro-firm data to assess the strength of human capital externalities in cities,and focuses on examining the mechanisms of human capital externalities generation from the perspective of communication frequency as well as quantifying their effective radiation distance.The findings are as follows:1.human capital has both positive spillover effects and negative competitive effects,with spillover effects dominating in creative services(e.g.,education,scientific research,professional and technical services,etc.)and competitive effects dominating in non-creative services(retail,restaurants,transportation,etc.),and the magnitude and direction of human capital externalities depend on the results of the superposition of these two effects.2.Communication in big cities is an important mechanism for the generation of human capital externalities.3.The effective spillover distance of human capital externality is very limited,even for creative services,the effective spillover distance of human capital externality is only about 3km.