How to compute ROC and AUC under ROC after training using caret in R?

Question

I have used caret package\'s train function with 10-fold cross validation. I also have got class probabilities for predicted classes by setting

Answer 1

Update 2019. This is what MLeval was written for (https://cran.r-project.org/web/packages/MLeval/index.html), it works with the Caret train output object to make ROCs, PR curves, calibration curves, and calculate metrics, such as ROC-AUC, sensitivity, specificity etc. It just uses one line to do all of this which is helpful for my analyses and may be of interest.

library(caret)
library(MLeval)

myTrainingControl <- trainControl(method = "cv", 
                                  number = 10, 
                                  savePredictions = TRUE, 
                                  classProbs = TRUE, 
                                  verboseIter = TRUE)

randomForestFit = train(x = Sonar[,1:60], 
                        y = as.factor(Sonar$Class), 
                        method = "rf", 
                        trControl = myTrainingControl, 
                        preProcess = c("center","scale"), 
                        ntree = 50)

##

x <- evalm(randomForestFit)

## get roc curve plotted in ggplot2

x$roc

## get AUC and other metrics

x$stdres