在factoextra包中對(duì)貢獻(xiàn)率有一個(gè)繪圖。圖中有參考線，高于此線的認(rèn)為變量是顯著的，隨著變量的多少這個(gè)值是不同的。

library(factoextra)

? ? library(FactoMineR)

? ? df <- decathlon2[1:23, 1:10]

? ? res.pca <- PCA(df,??graph = FALSE)

? ? fviz_contrib(res.pca, choice = "var", axes = 1, top = 10)

包的幫助中說了這個(gè)參考線，但沒說這個(gè)線對(duì)應(yīng)的值是多少：

A reference dashed line is also shown on the barplot. This reference line corresponds to the expected value if the contribution where uniform. For a given dimension, any row/column with a contribution above the reference line could be considered as important in contributing to the dimension.

終于眼尖的我在函數(shù)的原文件中找到了答案：

是100/length(contrib)

也就是100除以變量個(gè)數(shù)