价格支持政策对大豆全要素生产率的影响机制分析

Analysis of Price Support Policy’s Influence Mechanism on Soybean Total Factor Productivity

在超效率DEA模型测算价格支持政策时期大豆TFP的基础上,使用DID模型分析价格支持政策对大豆TFP的净效应及其影响路径。结果表明:价格支持政策的实施抑制了大豆TFP的有效提升,但存在结构性差异,市场化改革有助于改善大豆TFP;价格支持政策对大豆TFP产生的抑制作用持续性并不强;价格支持政策形成"消极生产率效应"的作用路径是其未带来有效的收益激励,财富水平和市场扭曲抑制了豆农改善生产要素配置状况的积极性。考虑到短期内无法缩小同玉米单产差距的实际,大豆生产者补贴政策若不能给予农户稳定的收益预期,则对改善TFP的作用不应过高估计。为此,在大豆生产者补贴政策调整和修正的过程中应加强系统的战略设计,由单一化的补贴激励转向多元化的政策支持。

Based on the Super-efficiency DEA model,the double difference model was used to analyze the net effect of price support policy on soybean TFP in the period of price and the specific impact path.The results show that the implementation of price support policy inhibits the effective improvement of soybean TFP,but there are structural differences and market reforms which help to improve soybean TFP while the suppressive effect of price support policy on soybean TFP is not strong and persistent.The price support policy produces the“negative productivity effect”because it does not bring effective income incentive,and the low level of wealth and market distortion restrain the enthusiasm of soybean farmers to improve the production factor allocation.Considering the fact that the gap with corn yield per unit area cannot be narrowed in the short term,the effect of current soybean producer subsidy policy on improving TFP should not be overestimated if it fails to provide stable income expectation for farmers.Therefore,in the process of adjusting and revising the soybean producer subsidy policy,we should strengthen the strategic design of the system,and shift from the single subsidy incentive to the diversified policy support.