The Impact of Regional Integration Policies on Innovation Efficiency--The Case of the Yangtze River Delta Urban Agglomeration

Can regional integration policies enhance the efficiency of urban innovation? To this end, this study employs a multi-period PSM-DID approach based on data from 285 prefecture-level cities in China from 2004 to 2020 and a quasi-natural experiment on regional integration in the Yangtze River Delta (YRD) region to assess the impact of the implementation of regional integration policies on the innovation efficiency of cities. The results show that (1) the impact of regional integration policies on urban innovation efficiency (TE) is positively facilitated.(2) This paper further discusses the impact of regional integration policies on innovation efficiency by taking into account the upgrading of industrial structure in Chinese regions and using industrial structure upgrading as a moderating variable, and the results show that upgrading of urban industrial structure enhances the impact of regional integration policies on urban innovation efficiency.(3) Based on the perspective of heterogeneity, in cities with smaller population size, lower economic development level and weaker transportation accessibility, regional integration policy has a more significant effect on the enhancement of urban innovation efficiency, which shows that regional integration policy can effectively bring into play the technological diffusion effect of the central cities such as Shanghai, Hangzhou and Nanjing.