摘要
本文应用时间序列分析的方法,对黑荆树林分平均直径、平均高和蓄积量的月总生长量的趋势项和随机项进行了研究,并建立了这二项的时间序列,叠合模型。据此对未来林分的各月总生长量进行了5步预测,其预测的绝对平均误差分别为1.62％、1.91％、3.24％,比仅用回归分析方法有效地提高了预测的精度。
By using a time series analysis, time-series-fold models were developed to study the terms of the trend and the terms of the stochastics of the total monthly increment for stand diameter, mean stand height and stand volume of wattle. The mean diameter model is:
The mean height model is:
The stand model is:
On the basis of the above models, five forecasts were engaged for the future total increment each month, and mean absolute errors are 1 . 62%, 1 . 91%, and 3.24%.
出处
《经济林研究》
1989年第1期62-69,共8页
Non-wood Forest Research
