Calculating ROC Curves and AUC
The previous exercises have demonstrated that accuracy is a very misleading measure of model performance on imbalanced datasets. Graphing the model's performance better illustrates the tradeoff between a model that is overly aggressive and one that is overly passive.
In this exercise you will create a ROC curve and compute the area under the curve (AUC) to evaluate the logistic regression model of donations you built earlier.
The dataset donors with the column of predicted probabilities, donation_prob, has been loaded for you.
Den här övningen är en del av kursen
Supervised Learning in R: Classification
Övningsinstruktioner
- Load the
pROCpackage. - Create a ROC curve with
roc()and the columns of actual and predicted donations. Store the result asROC. - Use
plot()to draw theROCobject. Specifycol = "blue"to color the curve blue. - Compute the area under the curve with
auc().
Interaktiv övning med praktiskt arbete
Testa den här övningen genom att slutföra den här exempelkoden.
# Load the pROC package
# Create a ROC curve
ROC <- roc(___, ___)
# Plot the ROC curve
plot(___, col = ___)
# Calculate the area under the curve (AUC)
auc(___)