基于Nerlove模型的我国大豆供给反应实证分析

Positive Analysis on Supply Response of Soybean in China Based on Nerlove Model

为了全面了解影响我国大豆供给的主要因素,基于2001-2014年全国10个大豆主产区大豆生产和价格的面板数据,同时引入替代作物收益、农业政策及时间趋势虚拟变量,运用Nerlove模型对我国大豆的供给反应进行了实证分析。结果表明:我国大豆的播种面积受滞后一期大豆播种面积和滞后一期大豆单价的显著正向影响,受滞后一期替代作物单位面积纯收益的显著负向影响;2008年出台的大豆临时收储政策这一变量的回归系数没有通过显著性检验,因此不能断定大豆临时收储政策对我国大豆的供给有作用;大豆种植户在决策时主要受以往多期大豆价格的影响;我国大豆供给对价格变化的反应并不敏感,短期价格弹性较小,长期有所提升,存在滞后性。最后提出了保障我国大豆供给的政策建议。

Based on the panel data of planting area and price of soybean from 2001to 2014in ten major production regions,the supply response of soybean in China was studied in this paper by using extended Nerlove model with the variables of alternative crops yield,agricultural policy and time trend.The result shows that:Firstly,the lag of area and unit price had significant positive influences on the supply of soybean,but the alternative crops yield had significantly negative influences on it.Secondly,the variables of temporary reserve policy failed to pass the test of significance,so it is hard to decide that this policy had impact on the soybean supply of China.Thirdly,soybean farmers were mainly affected by the previous several periods of soybean prices in decision-making.Fourthly,the soybean supply didn’t respond sensitively to the price.The soybean short-term price elasticity was lower than the long-term price elasticity and there existed a certain hysteresis.Finally,policy suggestions were proposed to ensure the soybean supply in China.