肯德尔和谐系数 (Kendall's Coefficient of Concordance)

它是被用来表示多列等级变量相关程度的指标。
- It was used as an indicator of the degree of correlation of multicolumn ranking variables.
常用于K个评定者对N个事物进行等级评定，考察这K个评定者之间评分的一致性。
- It is commonly used to rate N things by K raters and examine the consistency of ratings among these K raters.

其中 Ri 是每一个被评价事物的 K 个等级之和，K 为评定者的个数，N 为被评价的事物的个数。
- where Ri is the sum of K ratings for each thing evaluated, K is the number of raters, and N is the number of things evaluated.
W可以看作是所有可能的评定者对评定等级的 Spearman 相关系数的函数：
- W can be viewed as a function of the Spearman correlation coefficients of all possible raters for the rating scale.