自贸区设立对企业创新水平的影响研究

Research on the Impact of the Establishment of Free Trade Zones on the Level of Enterprise Innovation

基于2011—2020年沪深A股的上市公司面板数据,以自贸区设立为准自然实验,采用多期双重差分法实证检验自贸区设立对企业创新的政策影响,并借助多中介的因果机制分析法从融资约束和政府补助两方面分析其作用渠道。研究发现:自贸区的设立使得企业的创新产出提升12.9%,创新投入增加55.7%,其中发明专利数量增加14%,表明自贸区的设立能够显著提升企业的创新水平。该结论在经过动态性检验、反事实检验后依旧成立。从自贸区位置来看,沿海自贸区内企业创新产出水平提升效果比内陆自贸区更为显著;从企业类型角度来看,小规模、非国有、高新技术企业的创新水平更容易受到自贸区的政策影响。进一步分析可知,自贸区设立主要通过增加政府补助额、改善企业融资环境的方式来提高区内企业的创新水平。

Based on the panel data of listed companies in Shanghai and Shenzhen A-shares from 2011 to 2020,this paper uses the multi-period difference-in-difference method to empirically test the policy impact of the establishment of the free trade zone on enterprise innovation based on the natural experiment of the establishment of the free trade zone,and analyzes its impacting channels from the aspects of financing constraints and government subsidies with the help of multi-intermediary causal mechanism analysis.It is found that the establishment of the free trade zone has increased the innovation output of enterprises by 11.9%and the innovation input by 55.7%,among which the number of invention patents has increased by 14%.The above improvements indicate that the establishment of the free trade zone can significantly improve the innovation level of enterprises.This conclusion is still valid after the dynamic test and the counterfactual test.From the perspective of the location of the free trade zone,the improvement of the innovation output level of enterprises in the coastal free trade zone is more significant than that in the inland free trade zone.From the perspective of enterprise types,the innovation level of small-scale,non-state-owned and high-tech enterprises is more susceptible to the policies of the free trade zone.Further analysis reveals that the establishment of the free trade zone mainly improves the innovation level of enterprises in the zone by increasing the amount of government subsidies and improving the financing environment for enterprises.