单木生物量模型误差分析与定权方法探讨

Error Theory and Weighted - calculation Method on Single - Tree Biomass Model

长久以来,在林业上人们总是习惯于从已直接观测到的数据的拟合情况来选择生物量数学模型、讨论模型的精度,而缺乏对生物量数据本身的误差分析,因而很容易导致生物量数学模型在参数估计上产生偏差。因此,文章从生物量数据的获取着手,引入误差理论,详细地分析了生物量测定的误差来源,并由此详细讨论了在单木生物量模型建立过程中生物量测定误差和生物量数学模型误差的影响。同时引入了误差传播定律、协方差传播定律,从而在理论上证明了生物量拟合误差随自变量增大而增大的异方差性分布特点;根据生物量异方差性的误差分布特点,对生物量模型解算过程中的合理选权问题进行了探讨。

For a long term,in forestry research,people are always accustomed to choosing biomass model and discussing model precision according to direct data they obtained from their experiments. To discard the surveying error in their data leads to model parameter warp. Therefore, in this paper, authors have analyzed single tree biomass error source from forestry biomass surveying in detail. And, two influences both from surveying error and model error are presented. Least square estimation and robust estimation methods are all introduced to solve the problems of weighted-calculation in the study.