使用离散系数进行统计分析的一个误区

A Misunderstanding in Using Coefficient of Variation for Statistical Analysis

离散系数中平均数的选用与计算非常重要,它既决定了分子中标准差的大小,又构成了分母本身.在一些统计学教材和学习资料中经常见到不当运用平均数计算离散系数的例子.辨析此类应用,要遵循统计学一般原理,明确统计目的与统计方法,并据实际情况计算平均数与离散系数,避免陷入机械套用公式的误区.

It is very important to select and calculate the average when using the coefficient of variation(CV).The average not only determines the standard deviation in the molecule,but also constitutes the denominator itself.Examples of incorrect use of average can often be seen in some textbooks and exercises.To distinguish such applications,we should follow the principles of statistics,clarify the statistical purpose and methods,calculate the average and CV according to the actual situation,and avoid using the formula mechanically.