M-估计用于食用合成色素混合体系的同时测定

Simultaneous Determination of Mixed Edible Pigments With M-estimation

利用具有抗异常点干扰能力的Ａｎｄｒｅｗｓ型稳健Ｍ－估计，研究了在正常和异常情况下对色素二组分、三组分、四组分混合体系中各组分的同时测定。结果表明无论是否存在异常值，Ｍ－估计都能得到可信的结果，而传统的最小二乘法在有异常值时其结果将是毫无意义的。对Ｍ－估计中的重要参数的取值对结果的影响作了考察。本文还就Ｍ－估计所能承受的异常点个数作了初步探讨，表明Ｍ－估计是一种可以替代最小二乘法的优良参数估计方法。

The edible pigment additive of two, three and four components has been simulta- neously determined with the robust M-estimator of Andrews' type that possesses the resis- tance of outlier disturbance under normal and abnormal circumstances. Results show that outliers have no influence on M-estimator but significantly on leastsquares. We also studied the influence of the parameter b of M-estimator and the outlier size on results. All of these show that the M-estimator approach is a good method for parameter estimation and can re- p1ace the least-square method in some extent.