gini_norm: Normalized Gini score
In m-dz/mdmisc:

Description Usage Arguments Details Value Examples

Normalized Gini score for binary outcome modelling

1	gini_norm(actual, predictions)

`actual`	Actual outcome
`predictions`	Predicted outcome

Based on https://www.kaggle.com/wiki/RCodeForGini

Normalized Gini score

df <- data.frame(
  actual = c(1,1,1,1,1,0,1,1,1,0,1,1,0,1,1,1,1,0,0,0,1,0,1,0,0,0,1,0,0,0,0,0,0,1,0,0,0,0,0,0),
  predicted = seq(1, 0, length.out = 40)
)
gini_val <- gini_norm(df[, 'actual'], df[, 'predicted'])
## Compare to AUC from pROC package
# AUC_val <- pROC::roc(df[, 'actual'], df[, 'predicted'])$auc
# gini_val == 2 * AUC_val - 1