Examining CAP, ROC, and precision-sensitivity curves for binary classification
There are several ways to visualize the performance of a binary classification model. A relatively straightforward visualization is the Cumulative Accuracy Profile (CAP), which shows the ability of our model to identify in-class, or positive, cases. It shows the cumulative cases on the X-axis and the cumulative positive outcomes on the Y-axis. A CAP curve is a good way to see how good a job our model does at discriminating in-class observations. (When discussing binary classification models, I will use the terms in-class and positive interchangeably.)
Receiver operating characteristic (ROC) curves illustrate the tradeoff between model sensitivity (being able to identify positive values) and the false positive rate as we adjust the threshold for classifying a positive value. Similarly, precision-sensitivity curves show the relationship between the reliability of our positive predictions (their precision...