套期保值作为风险管理的重要工具,已得到广泛的应用。本文在GARCH模型的基础上提出了一种改进后的动态BGARCH模型,对大连商品交易所大豆的套期保值问题进行了实证研究。研究结果表明:基差对现货和期货风险结构的影响是不对称的,其中正基差对风险结构的影响要大于负基差的影响。从样本区间外各种对冲模型的保值效果看,考虑了基差非对称效应的对冲策略能更好地减小组合的风险。
As an important risk management tool,hedging has been used widely.This paper proposes an alternative specification of the BGARCH model in which the effect is incorporated for estimating MVHRs.Empirical investigation in commodity markets suggests that the basis effect is asymmetric,i.e.,the positive basis has greater impact than the negative basis on the variance and covariance structure.Out-of-sample comparisons of portfolio variances indicate that the model with the asymmetric effect provides greater risk reduction.