Calculate AUC in R?

Question

Given a vector of scores and a vector of actual class labels, how do you calculate a single-number AUC metric for a binary classifier in the R language or in simple English?

Answer 1

I usually use the function ROC from the DiagnosisMed package. I like the graph it produces. AUC is returned along with it's confidence interval and it is also mentioned on the graph.

ROC(classLabels,scores,Full=TRUE)