农业政策干预对玉米价格跨国传导的影响分析

Analysis of Impact of Agricultural Policy Intervention on Transnational Transmission of Corn Price

基于向量自回归和多变量BEKK模型,就贸易干预政策、临时收储政策和目标价格改革政策对世界玉米价格与中国玉米价格的传导关系进行了研究。结果表明:(1)中国东北主产区玉米价格与世界玉米价格不存在协整关系;东北产区玉米价格受自身ARCH型波动溢出效应和GARCH型波动溢出效应的影响较大;(2)在贸易政策干预前、贸易政策干预和目标价格改革阶段,世界玉米价格对东北产区玉米价格存在比较显著的单向均值溢出效应;在临时收储政策阶段,世界玉米价格对东北产区玉米价格影响不显著。在实施进口配额制度的情况下,临时收集政策的实施进一步加剧了中国东北玉米市场价格与世界玉米市场的不协调,破坏了世界较低的玉米价格向中国市场的传导。

Based on the vector autoregression and the multivariate BEKK models,the transmission relationship between the world’s corn price and China’s corn price through trade intervention policies,temporary purchase and storage policies and target price reform policies was studied.The results showed that there was no co-integration relationship between corn prices in main production areas in Northeast China and the world.The corn price in Northeast China was greatly affected by their own ARCH-type volatility spillover effects and GARCH-type volatility spillover effects.At the stages of pre-trade policy intervention,policy intervention and target price reform,there was a significant one-way mean spillover effect of the world’s corn price on corn price in production areas in Northeast China.At the temporary purchase and storage policy stage,the world’s corn price had no significant effect on corn pricec in Northeast producing areas.Under the import quota system,the temporary purchase and storage policy further aggravated the uncoordination between corn market price in Northeast China and the world corn market,which destroyed the transmission of Word corn’s of lower price to Chinese market.