基于双重差分模型的清洁取暖补贴效果量化评估

财政补贴是顺利推进北方地区冬季清洁取暖试点工作的重要保障。本文综合运用双重差分(Difference in Differences,DID)等计量模型统计方法,量化评估了清洁取暖补贴措施对试点城市空气质量的改善效果。研究发现:清洁取暖补贴对试点城市采暖月CO、PM10和PM2.5浓度均有显著改善作用,且对第一批试点城市的贡献更大,使得第一批试点城市采暖月CO、PM10和PM2.5浓度分别较补贴前显著降低0.411mg/m^3、22.53μg/m^3和15.45μg/m^3,对污染物浓度下降的贡献度分别为56.0%、65.2%和49.8%;清洁取暖补贴对第一批试点城市采暖月SO2浓度的改善效果不显著,却使第二批试点城市采暖月SO2浓度较补贴前显著降低24.53μg/m3,对SO2浓度下降的贡献度为55.2%;清洁取暖补贴效果是地方重视程度、治理能力、一系列污染防治措施以及气象条件等共同作用的结果。建议:第一,构建和完善差异化补贴机制;第二,优化调整清洁取暖补贴资金使用方式;第三,引导地方政府探索建立中长期清洁取暖财政补贴机制。

Quantitative evaluation on the effect of clean heating subsidy based on DID estimation

Financial subsidy is considered as one of the important guarantees for smoothly promoting the implementation of clean heating pilots in winter in Northern China.By using the DID model estimation and RDA statistical methods, this paper conducts the effect evaluation of the policy of clean heating subsidy on the pilot cities.There are the following results:(1) Clean heating subsidy has significantly achieved the monthly average concentration improvement of CO, PM10 and PM2.5, and contributed much more during the winter heating months for the first pilot cities, which decreases the monthly average concentration of CO, PM10 and PM2.5 by 0.411 mg/m3, 22.53μg/m3 and 15.45μg/m^3 respectively, with the corresponding contribution was 56.0%,65.2% and 49.8%.(2) Clean heating subsidy has no significant effect on the monthly concentration of SO2 in the heating seasons for the first pilot cities, but the monthly average concentration of SO2 in the second pilot cities is significantly lower by 24.53μg/m^3 than that before the subsidy policy.(3) Significant progress has been made for clean heating subsidy policy, mainly due to the combined effect of various positive factors such as local emphasis, governance capabilities, a series of pollution prevention measures and meteorological conditions.The following suggestions are put forward:(1) Establish and improve a differentiated subsidy mechanism.(2) Optimize and adjust the reasonable use of clean heating subsidy.(3) Guide local governments to explore the establishment of medium and long-term subsidy mechanisms towards clean heating.