价格支持政策对我国不同粮食作物播种面积变化的影响差异

THE IMPACT OF PRICE SUPPORT POLICIES ON THE CHANGES OF FOOD CROPS PLANTING AREAS IN CHINA

关键词:  价格支持政策粮食作物播种面积PSM DID方法Nerlove模型

Key words:  price support policy  food crops  planting area  PSM DID moth  Nerlovel model

摘要:

［目的］文章评估了价格支持政策对不同粮食作物播种面积变化的平均效应与动态效应，并测度多种价格支持政策的交叉政策弹性。［方法］基于1998—2016年实施粮食价格支持政策省份面板数据，设立对照组，利用倾向得分匹配—双重差分方法（PSM DID）评估价格支持政策平均效应与动态效应，并构建粮食作物供给反应（Nerlove）模型测度价格支持政策的交叉政策弹性。［结果］（1）价格支持政策对水稻、小麦、玉米播种面积增加具有不同程度的推动作用，按大小依次为玉米>水稻>小麦，对大豆播种面积变化影响不显著； （2）价格支持政策持续时间越长，对水稻、玉米播种面积增加的推动作用越大，对小麦播种面积增加的推动作用较为稳定； （3）小麦、玉米播种面积变化主要来自自身价格支持政策，水稻播种面积变化除了受到自身价格支持政策影响外，还受到其他作物政策影响，大豆播种面积变化对玉米临储政策反应敏感，对自身价格支持政策反应不敏感。［结论］在制定粮食政策时既要区分政策及其持续性对不同粮食播种面积变化的影响差异，又要注意在同一地区实施多种粮食政策时，可能对不同作物产生交叉影响。

Abstract:

This paper evaluated the average effect and dynamic effect of price support policies on the changes of planting area of different crops, and measured the cross policy elasticity of multiple price support policies. Based on the panel data of the provinces implementing price support policies from 1998 to 2016, this paper established control groups, and used the PSM DID method to evaluate the average effect and dynamic effect of price support policies, further measured the cross policy elasticity by the Nerlove model . The results showed that: (1)The price support policy had positive effects on the planting area of rice, wheat and corn, and with larger effect on corn, followed by rice and wheat, but it had no significant effect on the soybean planting area. (2) The longer the price support policy maintained, the greater the promotion effect on the planting area of rice and corn had, and the effect on wheat planting area was relatively stable. (3) The changes in the wheat and corn planting area were mainly related to respective price support policy, and the changes of rice planting area were affected by rice price support policy and other crop policies, for changes in the soybean planting area were sensitive to corn′s storage policy, but not to soybean price support policy. Therefore, it is necessary to distinguish the different policy impacts for crops, and pay attention to the regional cross effects from various policy when multiple supporting policies are implemented in the same region.