“撤县设区”对城市创新水平的影响研究——基于PSM-DID模型的实证分析

Research on the Impact of“Revoke County to Urban District”on Urban Innovation Level——Empirical Analysis Based on PSM-DID Model

本文选取2007—2019年的城市面板数据,运用双重差分倾向得分匹配模型(PSM-DID)检验了“撤县设区”对城市创新水平的影响及作用机制。研究结果表明:(1)“撤县设区”能够显著提升城市的创新水平,经过一系列稳健性检验,该结论仍具有稳健性。(2)“撤县设区”对城市创新水平的影响具有显著的异质性,具体表现为其对行政级别一般的城市具有显著提升作用,但对行政级别较高的城市作用却不明显;在适度规模的城市实施“撤县设区”能够显著提升城市创新水平,而在规模过大或过小的城市实施的作用却不显著;相比于策略创新,“撤县设区”推动了真正意义上的质量创新。(3)作用机制的研究结果表明,“撤县设区”通过扩大市场规模、强化产业集聚、优化营商环境和改善城市人居环境提升城市创新水平。(4)“撤县设区”的“扩散效应”大于“虹吸效应”,具有显著的正向政策空间溢出效应,表明其能通过“知识溢出”提高周边城市的创新水平。

This paper selects the urban panel data from 2007 to 2019,and uses the difference-indifferences propensity score matching method(PSM-DID)to test the impact and mechanism of“Revoke County to Urban District”on the level of urban innovation.The results show that:(1)“Revoke County to Urban District”can significantly improve the city’s innovation level.After a series of robustness tests,the conclusion is still robust.(2)The impact of“Revoke County to Urban District”on the level of ur⁃ban innovation has significant heterogeneity.Specifically,it has a significant improvement effect on cities with general administrative levels,but the effect on cities with higher administrative levels is not obvious.The implementation of“Revoke County to Urban District”in cities of moderate scale can significantly im⁃prove the level of urban innovation,but the effect of implementation in cities of too large or too small scale is not significant.Compared with strategic innovation,“Revoke County to Urban District”has promoted quality innovation in the true sense.(3)The research results of the mechanism of action show that“Re⁃voke County to Urban District”can improve the level of urban innovation by expanding the market scale,strengthening industrial agglomeration,optimizing the business environment,and improving the urban liv⁃ing environment.(4)The diffusion effect of“Revoke County to Urban District”is greater than the si⁃phon effect,which has a significant positive policy spatial spillover effect and can improve the innovation level of surrounding cities through knowledge spillover.