国家创新型城市试点政策的效果以及空间溢出

国家创新型城市试点政策逐渐向全国推广，然而在中国独特的治理结构下这种实验主义治理能否转化为治理效能，其空间溢出效果如何，鲜有从实证的角度进行研究。本研究基于270个地级及以上城市的面板数据，将国家创新型城市试点设立作为自然实验，运用双重差分法考察其政策效果，研究结果表明：（1）国家创新型城市试点政策对城市创新力的提升作用显著，但动态效应显示，这种政策效应有逐年减弱趋势。（2）异质性检验结果表明，创新型城市试点政策效果在东、中、西三个地区呈现差序格局。（3）进一步的空间杜宾效应研究表明，创新型城市试点政策具有空间溢出效应，不仅促进了试点地区的城市创新力的提升，而且对相邻城市创新力提升影响显著。金融发展水平、产业结构都可以有效地促进本地创新水平，且对邻近地区具有溢出效应，而人力资本则对邻近地区创新力提升具有挤出效应。稳健性检验支持上述的结论。基于实证结果，提出推动创新型城市有序扩散，强化政策的空间辐射效应；设计创新型城市政策的梯度发展战略，促进地区间的协同发展等政策建议。

Research on the Policy Effect and Spatial Spillover of the National innovative City Pilot Policy

The pilot policy of national innovative cities has been gradually extended to the whole country. However, under the unique governance structure of China, whether this kind of experimental principal governance can be transformed into governance efficiency and its spatial spillover effect are rarely studied from an empirical point of view. Using the panel data of 270 cities at or above prefectural level, this study takes the pilot establishment of national innovative cities as a natural experiment, and uses the double difference method to investigate the policy effect. The main results are as follows: (1) the national innovative city pilot policy has a significant effect on the promotion of urban innovation, but the dynamic effect shows that it has a weakening trend year by year.(2) the results of heterogeneity test show that the effect of innovative urban pilot policy shows a differential order pattern in the eastern, central and western regions. (3) further research on spatial Dubin effect shows that the pilot policy of innovative cities has spatial spillover effect, which not only promotes the improvement of urban innovation in pilot areas, but also has a significant impact on the innovation of neighboring cities. The level of financial development and industrial structure can effectively promote the level of local innovation, and have spillover effects on neighboring areas, while human capital has crowding out effect on the promotion of innovation in neighboring areas. The robustness test supports the above conclusions. Based on the empirical results, this paper puts forward some policy suggestions, such as promoting the orderly diffusion of innovative cities, strengthening the spatial radiation effect of policies, designing the gradient development strategy of innovative urban policies, and promoting the coordinated development of regions.