根据1983-2008年中国小麦生产的时间序列数据,采用H-P滤波法对中国小麦产量波动性进行了分析。结果表明,在1983-2008年间小麦生产包括了6个完整的周期,平均年距为4.5年,其中扩张期的长度平均为2.5年,而收缩期的平均值为1.7年,扩张与收缩长度之比在逐期下降,说明中国小麦产量扩张能力正在下降。通过建立多元线性回归方程,验证了中国小麦产量的波动与单产波动及种植面积波动的关系,估计得出种植面积对小麦产量的波动影响程度大于单产,应继续确保种植面积来平抑小麦产量的波动。
Based on the time series data of wheat output in China during 1983-2008,the fluctuation of wheat output was analyzed by H-P filtering method.The results showed that the wheat output in 1983-2008 included 6 integrated cycles with average year space of 4.5 years.The length of expansion period was 2.5 years,while of contraction period was 1.7 years.The length ration of expansion period and contraction period was decreasing every period,indicating that the expansion ability of wheat output in China was decreasing.By establishing the multivariate linear regression equation,the relationship between the fluctuation of wheat output and fluctuation of per unit area yield and planting area was verified.It was estimated that the planting area had much effect on the fluctuation of wheat output than per unit area yield.The planting area should be ensured to stabilize the fluctuation of wheat output.