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.
Deze oefening maakt deel uit van de cursus
Supervised Learning in R: Classification
Oefeninstructies
- 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().
Praktische interactieve oefening
Probeer deze oefening eens door deze voorbeeldcode in te vullen.
# Load the pROC package
# Create a ROC curve
ROC <- roc(___, ___)
# Plot the ROC curve
plot(___, col = ___)
# Calculate the area under the curve (AUC)
auc(___)