R Data Analysis Cookbook, Second Edition - Second Edition

Generating receiver operating characteristic charts

When using classification techniques, we can rely on the technique to classify cases automatically. Alternately, we can rely on the technique to only generate the probabilities of cases belonging to various classes and then determine the cutoff probabilities ourselves. A receiver operating characteristic (ROC) chart helps with the latter approach by giving a visual representation of the true and false positives at various cutoff levels. We will use the ROCR package to generate ROC charts.