Transportation Network,Knowledge Access And City Innovation An Inquiry Based On High-speed Railway And Patent

As the growth point and power source of building an innovative country,urba n innovation is the key to China's independent innovation and catching up.As the fastest-growing field in China's infrastructure construction,high-speed railway has important strategic significance in the improvement of transportation network.The busy trunk lines of the high-speed rail connects the cities scattered in the land of China and becomes the main artery of the national economy.It may play an important role in supporting and leading the economic and social development and the improvement of urban innovation capability.This paper examines the aggregate impact of transportation infrastructure network changed by high-speed railway(HSR)on the city's patent applications for invention,which is based on China's prefecture-level city's panel data about patents,along with the "Knowledge Access" index build on railway mileage and operating speed through calculating the shortest path by the Dijkstra's algorithm.As revealed by the results,firstly,transportation infrastructure optimized the launch of the HSR will improve city's Knowledge Access,and then exerts significant positive effects on city's patent innovation through knowledge spillover.In addition,this effect still reins significant even when taking the explanatory variable to be lag one phase.Meanwhile,several robust checks like proxy variables confirm the reliability of conclusion.Secondly,heterogeneity research show that patent applications for invention in each industry are positively related to explanatory variable,especially for residential services.In addition,I divide cities into two groups respectively according to the initial endowment of transportation and knowledge,and the result suggest that cities with lower endowment in transportation or k:nowledge will benefit more from HSR network in the aspect of patent innovation.Furthermore,by dividing cities into groups based on the condition that whether the city has been directly included in high-speed rail network,I find that the city which has directly connected to high-speed rail network has benefit more from knowledge spillover.