长江经济带一体化发展对城市生态效率的影响——基于PSM-DID模型的实证分析

Impact of Integrated Development of the Yangtze River Economic Belt on Urban Ecological Efficiency——An Empirical Analysis Based on PSM-DID Model

采用SBM-Undesirable模型对2007~2017年我国286个城市生态效率进行测度,利用长江经济带一体化发展作为一项准自然实验,运用PSM-DID以及一系列稳健性检验方法评估了长江经济带一体化发展对城市生态效率的政策效果。结果发现:长江经济带一体化发展显著提升了沿线城市的生态效率,通过一系列检验后,证明该结论依然稳健。进一步运用中介效应模型研究影响机制,结果发现长江经济带一体化发展有利于经济发展、产业结构升级以及科技进步,并通过经济增长效应、产业结构效应和技术创新效应改善城市生态效率。

This paper measures the ecological efficiency of 286 cities in China from 2007 to 2017 by SBM undesirable model. Taking the integrated development of the Yangtze River Economic Belt as a quasi-natural experiment, it uses PSM-DID and a series of robustness test methods to evaluate the policy effect of the integrated development of the Yangtze River Economic Belt on the urban ecological efficiency. Result shows that the integrated development of the Yangtze River Economic Belt significantly improves the ecological efficiency of cities along the line. Results remain robust after a series of tests.Using the intermediary effect model to study the impact mechanism, it is found that the integrated development of the Yangtze River economic belt is conducive to economic development, industrial structure upgrading and scientific and technological progress, and can improve the urban ecological efficiency through scale effect, structure effect and technology effect.