中国城市人力资本水平与人口集聚对创新产出的影响

基于中国2007—2012年287个地级及以上城市的创新投入要素和专利申请量的面板数据（未含港澳台地区数据），采用面板固定效应模型和面板分位数回归模型，揭示人力资本水平提升对区域创新产出的影响机制及其区域异质性，以及人口空间集聚对人才创新驱动作用的调节机制。结果表明：① 平均而言，人力资本水平越高的城市，创新产出水平越高，但人口集聚程度与创新产出水平并不存在显著的关联；② 人力资本水平提升对创新的驱动作用存在区域差异，在创新等级越低的城市中其作用效果越强；③ 人口空间集聚强化了人力资本水平对创新的驱动作用，城市规模扩大促进了知识的溢出；④ 人口空间集聚调节作用的显现需要达到一定的创新基础门槛，城市创新等级越高，调节作用越强。因此，各地方政府应当结合当地发展的实际情况，制定适宜的人才培育和人才引进策略，合理引导人才流动。

Impact of Human Capital Stock and Population Concentration on Innovative Output in China

This article aims to investigate the impact of human capital stock on innovation output in China, particularly focusing on its regional heterogeneity, using the panel data of patent application and innovation input among 287 prefecture-level cities from 2007 to 2012 (excluding the data of Hong Kong, Macau and Taiwan). In particular, we use two indicators, the percentage of highly educated talents and the average year of schooling, to capture the level of human capital accumulation. We use the number of patent applications as a proxy for innovation output and population density as a proxy for the level of population concentration. We use fixed-effect models to estimate the linkage between human capital stock and innovation output at the prefecture level and panel quantile regressions to capture the regional heterogeneity. Finding from regressions show that, on average, increased stock of human capital is associated with more innovation outputs, and population concentration is not significantly directly linked to innovation output. The effect of human capital accumulation on innovation output varies from one city to another, and this effect is stronger in cities that situate in the lower rung of innovation hierarchy. The concentration of population is found to strengthen the positive impact of human capital accumulation on innovation, and the increase in urban size is found to promote knowledge spillovers. The moderating effect of population concentration on the relationship between human capital stock and innovation output occurs when the innovation capacity of a city reaches a certain threshold. This moderating effect becomes stronger with an increase in a city’s innovation capacity. Therefore, policymakers are advised to formulate and implement appropriate policies to attract and cultivate talents and to encourage movement of talents, considering the innovation capacity and urban size .