我试图找到R函数来计算基尼系数和R中的AUC . 我找到了包 ROCRMLmetrics . 通常你可以在AUC和Gini之间切换

基尼= 2 AUC -1

在下面的例子中,对于2个exaplantory变量的情况,这是正确的,但对于仅一个变量的情况则不是这样 .

这是包装中的缺陷吗?

library(ROCR)
library(MLmetrics)

data(cars)
## 2 explanatory variables
logreg <- glm(vs ~ hp + wt,
              family = binomial(link = "logit"), data = mtcars)

pred = prediction(logreg$fitted.values, mtcars$vs)
auc_perf = performance( pred, measure = "auc" ) 
## both lines give 0.8968254
2*auc_perf@y.values[[1]]-1
Gini(y_pred = logreg$fitted.values, y_true = mtcars$vs)

plot( performance( pred, "tpr", "fpr" )  )

## 1 explanatory variable
logreg <- glm(vs ~ hp ,
              family = binomial(link = "logit"), data = mtcars)

pred = prediction(logreg$fitted.values, mtcars$vs)

auc_perf = performance( pred, measure = "auc" ) 

## different results:
2*auc_perf@y.values[[1]]-1
Gini(y_pred = logreg$fitted.values, y_true = mtcars$vs)

plot( performance( pred, "tpr", "fpr" )  )

会话信息是:

R版本3.4.3(2017-11-30)平台:x86_64-w64-mingw32 / x64(64位)运行于:Windows 7 x64(build 7601)Service Pack 1 Matrix产品:默认语言环境:[1] LC_COLLATE = German_Austria.1252 LC_CTYPE = German_Austria.1252 [3] LC_MONETARY = German_Austria.1252 LC_NUMERIC = C [5] LC_TIME = German_Austria.1252附加基础包:[1] stats graphics grDevices utils数据集方法基于其他附加包:[1] MLmetrics_1 .1.1通过命名空间加载的ROCR_1.0-7 gplots_3.0.1(未附加):[1] compiler_3.4.3 tools_3.4.3 KernSmooth_2.23-15 gdata_2.18.0 [5] caTools_1.17.1 bitops_1.0-6 pacman_0 . 4.6 gtools_3.5.0