磷吸附拟合方法比较及参数准确性分析  

Comparison of Different Fitting Methods for Phosphorus Sorption and Accuracy Analysis of Their Parameters

作　　者：黄利东[1] 杨军民[1] 刘亚楠[1] 闫宁[2] 

机构地区：[1]南京信息工程大学应用气象学院,江苏南京210044 [2]中国农业科学院烟草研究所,山东青岛266101

出　　处：《江西农业学报》2014年第11期113-119,123,共8页Acta Agriculturae Jiangxi

基　　金：国家自然科学基金项目(41201515);安徽中烟工业有限责任公司科技计划项目(2014124;2014125)

摘　　要：数据结构和方程形式对获取磷吸附模型的参数有直接的影响。针对目前磷吸附拟合中的常用模型,分析了模型线性变换对拟合结果的影响,讨论了影响参数的因素。主要结果包括:(1)数据误差的存在使得线性和非线性Langmuir方程获取的参数不同,非线性方程对数据有较好的拟合效果;(2)在吸附总体数据的随机干扰项服从均值为0、方差为σ2的正态分布(独立同分布)条件下,非线性拟合所获参数近似符合t分布,据此可提供参数的置信区间估计;(3)决定系数(R2)受自由度、参数个数、方程变换和极端数据点的影响。Data structure and equation form have direct influences on acquiring the parameters of phosphorus sorption models. Aiming at the common fitting models for phosphorus sorption at present, the author analyzed the effects of linear transformation of model on fitting results, and discussed the factors affecting the parameters of model.The main results included：（1） The existence of data error made that the acquired parameters of linear and non-linear Langmuir equations were different, and non-linear equation had better fitting effect on the data;（2） Under the assumptive conditions that the random disturbance term （μ） of phosphorus sorption conceptual data submitted to the normal distribution （independently identical distribution） of N（0, σ2）, the parameters obtained by non-linear fitting approximately matched t-distribution, hereby the confidence interval estimation of parameters could be provided.（3） The coefficient of determination （R2） was largely affected by degree of freedom, number of model parameters, equation transformation, and extreme data point.

关 键 词：磷吸附 LANGMUIR 线性方程 非线性方程 区间估计 决定系数 

分 类 号：S153.61[农业科学—土壤学] X132[农业科学—农业基础科学]