空间集聚、创新相互依存与城市经济增长外部性

Spatial Agglomeration, Innovation Interdependence and Externality of Urban Economic Growth

城市群、都市圈等空间集聚战略已经成为现阶段我国培育增长动力源、实现经济高质量发展的重要抓手,使用2001-2018年我国264个地级以上城市数据资料,基于动态空间杜宾模型考察空间集聚、技术创新与经济增长的内在关联,探究城市群战略的经济机理,结果发现:(1)空间集聚、技术创新的直接效应及其交互作用均对城市经济增长具有显著影响。从空间集聚多维指标看,资本、人口、企业聚集程度每增加10%,将导致城市经济产出分别增长6.17%、0.34%和0.2%;技术创新水平每提高10%,将使得城市经济产出增长0.45%;技术创新与人口集聚对城市经济增长具有积极性交互作用。(2)城市经济增长存在显著的空间外部性,邻近城市、次邻近城市的经济增长会对本城市产生溢出效应,且经济增长外部性随距离增加而呈现递减态势。(3)相比较而言,人口、资本要素在东部地区的集聚对经济增长的直接效应比中西部地区分别强14%和12%,企业向东部地区城市集聚能够诱发更为强烈的空间外部效应;技术创新的直接效应及其与人口集聚的交互效应对经济增长的影响同样表现出东部强于中西部的特征。

The spatial agglomeration strategies such as city clusters and metropolitan circles are vital for China to foster growth drivers and achieve high-quality economic development at this stage. Based on the data of 264 cities above the prefecture level in China from 2001 to 2018 and the dynamic spatial Durbin model, this paper observes the internal relationship between spatial agglomeration, technological innovation and economic growth, and explores the economic mechanism of city cluster strategy. The findings are as follows.(1) The direct effects of spatial agglomeration,technological innovation and their interactions have a significant impact on urban economic growth. From the perspective of the multi-dimensional indicators of spatial agglomeration, a 10% increase in capital, population, and enterprise agglomeration leads to an increase in urban economic output of 6.17%, 0.34% and 0.2% respectively. A 10%increase in technological innovation level increases the urban economic output by 0.45%. Technological innovation and population agglomeration have a positive interaction effect on urban economic growth.(2) Urban economic growth exhibits significant spatial externalities. The economic growth of neighboring cities and next-nearest cities has a spillover effect on the city, and the externalities of economic growth diminish with distance.(3) In comparison, the direct effects of population and capital agglomeration on economic growth in eastern region are respectively 14% and12% stronger than in central and western regions. The agglomeration of enterprises in eastern cities induces stronger spatial externalities. The direct effect of technological innovation and its interaction effect with population agglomeration on economic growth are also stronger in eastern region than central and western regions.