森林保险保费补贴政策的林业产出规模效应实证分析——基于双重差分模型与事件研究模型

森林保险保费补贴政策在中国实施已超10 a,其能否和在多大程度上促进林业生产的命题亟待科学系统的实证考查。为此,特结合生产者行为理论探寻森林保险保费补贴政策的林业产出规模效应,剖析森林保险保费补贴政策对林业产出的作用机理。在此基础上,基于2001—2017年中国31个省区市的面板数据,以2009年森林保险保费补贴政策冲击为自然实验,综合运用双重差分模型与事件研究模型实证分析该补贴政策对林业产出的影响及其长期动态影响效果,并进行2项安慰剂实验以排除研究结论的2个潜在威胁。结果表明:森林保险保费补贴政策对林业第一产业涉林产值有显著(P<0.1)正向影响,且影响效果随政策实施时间的推进而不断增强。补贴政策实施后,试点省较非试点省区市的林业第一产业涉林产值平均增加了104万元。以2010年为政策冲击年进行稳健性检验,所得结论与以2009年为政策冲击年进行分析的结果一致。安慰剂实验的结果排除了本研究结论的2个潜在威胁。研究结果对中央财政补贴下森林保险的作用持肯定态度,建议应从补贴对象瞄准、补贴规模科学测算、补贴标准合理设定等方面优化森林保险保费补贴政策,以增强其产出效应。

Empirical analysis on scale effect of forest output of forest insurance premium subsidy policy in China: based on difference-in-differences model and event study model

The forest insurance premium subsidy policy has been implemented for more than 10 years in China, and the proposition of whether and to what extent it can promote forestry production is in urgent need of scientific and systematic empirical test. Combined with producer behavior theory, we explored the scale effect of forest insurance premium subsidy policy on forest output, and analyzed the mechanism of forest insurance premium subsidy policy on forest output. On this basis, by using panel data of 31 provinces (autonomous regions, municipalities) in China from 2001 to 2017, and taking the impact of China’s forest insurance premium subsidy policy in 2009 as a natural experiment, we explored the impact of the subsidy policy on the forest-related output value of the primary forestry industry via difference-in-differences model and event study model. Two placebo tests were also carried out to rule out the potential threat of conclusions. The results showed that the forest insurance premium subsidy policy had a significant (P<0.1) positive effect on forestry output, and the effect would increase with the prolonged time of implementation. After the implementation of the subsidy policy, the forest-related output value of the primary forestry industry in pilot regions increased by 1.04 million yuan compared with that in non-pilot regions. Moreover, the robustness test was carried out in 2010 as the year of policy impact, and the conclusions were consistent. Additionally, two placebo trials also ruled out two potential threats to the results. The study held a positive attitude towards the role of forest insurance under the central financial subsidy, and it was suggested that the subsidy policy should be further optimized from the aspects of subsidy scale and subsidy standard to enhance its output effect.