环境规制有助于提升绿色全要素生产率吗?——基于两控区政策的估计

Can Environmental Regulation Promote GTFP?——Evidence from the Two Control Zones Policy

本文在以非径向、非角度的SBM方向性距离函数测算中国地级以上城市的绿色全要素生产率(GTFP)指数的基础上,将1998年提出的两控区政策作为一次准自然实验,采用倾向得分匹配与双重差分相结合的方法评估两控区政策对GTFP的影响。研究结果表明,两控区政策的实施显著抑制中国城市GTFP的提升,该结论在经过一系列稳健性检验之后仍然成立。究其原因,两控区政策不仅能通过约束政府规模和促进技术进步给GTFP带来正向影响,也能通过人力资本和能源消耗抑制GTFP的提升,并且后一种影响的程度超过前一种。值得注意的是,两控区政策并未显著降低中国城市的能源消耗与污染排放,这可能是两控区政策未能促进中国城市绿色发展的主要原因。此外,两控区政策对东部和中部城市的GTFP无显著影响,却会显著抑制西部城市的GTFP,对经济特区城市和非经济特区城市的GTFP均有显著影响,但影响方向正好相反。

Based on the non-radial and non-directional SBM directional distance functions, this paper calculates green total factor productivity (GTFP) index of cities above the prefecture level in China, and uses propensity score matching approach coupled with difference-in-difference regression analysis to assess the impact of the Two Control Zones policy on the GTFP by considering the Two Control Zones policy proposed in 1998 as a quasi-natural experiment. The results show that the implementation of the Two Control Zones policy significantly inhibits the promotion of GTFP in Chinese cities, which still holds after a series of robustness tests. The reason is that the two-zone policy can not only positively affect GTFP by reducing government size and promoting technological progress, but also negatively affect GTFP by human capital level and energy consumption, and the influential degree of the latter exceeds that of the former. It is worth noting that the two-zone policy has not significantly reduced energy consumption and pollution emissions in Chinese cities. This may be the main reason why the two-zone policy failed to promote the green development of Chinese cities. In addition, the two-zone policy has no significant impact on GTFP in eastern and central cities, but it will significantly inhibit GTFP in western cities. Moreover, the Two Control Zones policy has a significant impact on the GTFP of the Special Economic Zone cities and non-Special Economic Zone cities, but the effect direction is opposite.