绘制曲线ROC em R

Question

我需要在R中绘制ROC曲线，但我不知道如何修正它。

cctrl2 <- trainControl(method = "cv", number = 10, classProbs = TRUE, savePredictions = TRUE)
modelNb <- train(Treino[, -5], Treino$TOTAL_PEDIDO, 
         method = "nb", 
         trControl = cctrl2)
test_class_pred_nb_probs <- predict(modelNb, Teste[, -5], type = "prob")
roc_nb = plot.roc(Teste[, 2],test_class_pred_nb_probs$alto, col='red')

aux<-Teste[which(Teste$TOTAL_PEDIDO == "alto"),]
test_class_pred_nb_probs <- predict(modelNb, aux[, -5], type = "prob")
roc_nb = plot.roc(aux[, 2],test_class_pred_nb_probs$alto, col='red')

并显示以下消息：

Error in sort.list(y) : 'x' must be atomic for 'sort.list'
Have you called 'sort' on a list?

Answer 1

cctrl2 <- trainControl(method = "cv", number = 10,  classProbs = TRUE, savePredictions = TRUE)

modelNb <- train(Treino[, -2], Treino$TOTAL_PEDIDO,
              method = "nb", 
              trControl = cctrl2)

test_pred_nb <- predict(modelNb, Teste[, -2])
test_pred_nb_probs <- predict(modelNb, Teste[, -2], type = "prob")
roc_nb = multiclass.roc(Teste[, 2],
     test_pred_nb_probs$min,
     add=TRUE,
     col='blue')
roc_nb
rs <- roc_nb[['rocs']]
plot.roc(rs[[1]])

auc(roc_nb)