自由贸易试验区促进了制造业企业创新吗?--基于多期双重差分法的实证研究

Does Free Trade Zone Promote Manufacturing Enterprise Innovation?--Empirical Study Based on Multi-period Difference-in-Difference Method

基于2009—2019年制造业上市企业微观面板数据,利用多期双重差分法,研究自贸区试点政策对制造业企业创新水平的影响,并利用调节效应模型检验其实现路径。结果表明:自贸区试点政策显著促进了区内制造业企业专利申请与授权数量增加,从而提升区内制造业企业创新水平,研究结论在一系列稳健性检验中均成立。研究发现:自贸试验区通过提升研发投入促进效应、增强市场竞争倒逼效应和缓解融资约束便利效应的调节作用,显著正向促进了制造业企业创新水平。当企业研发投入强度越大、市场竞争程度越强、融资约束程度越弱时,自贸试验区对制造业企业创新水平的正向影响越大。异质性分析表明:自贸区试点政策的创新促进效应对非国有和高新技术制造业企业更为明显。

Based on the micro-panel data of listed manufacturing enterprises from 2009 to 2019,this paper tests the impact of the policy of Free Trade Zone on manufacturing enterprise innovation by using multi-period difference-in-difference method.And then,it tests its implementation path by the moderating effect model.Results show that,the policy of Free Trade Zone significantly promotes the number of patent applications and granted of manufacturing enterprises in the zone,thus promoting the innovation level of manufacturing enterprises,this conclusion is stll valid after a series of robustness tests.Free trade zone significantly promotes the level of manufacturing enterprise innovation via increasing enterprise R&D investment intensity,improving market competitiveness,and weakening financial constraints.When the R&D investment intensity of enterprises is greater,the market competitiveness is higher,and the degree of financing constraints is weaker,the positive impact of the FTZ on the innovation level of manufacturing enterprises is greater.Heterogeneity test shows that the innovation promotion effect of the policy of Free Trade Zone is more obvious for non-state-owned manufacturing enterprises and high-tech manufacturing enterprises.