I am using the pROC package in R to generate ROC curves. Using the "coords" function, I can extract the sensitivity (Se) , specificity (Sp), negative predicted value (NPV) and positive predicted value (PPV) for different thresholds. I also calculated the Se, Sp, NPV and PPV for some thresholds using the Caret package to compare.
I am a bit confused as the Se an Sp given by the pROC package are actually the NPV and PPV given by the Caret package, respectively (and conversely, the NPV and PPV given by pROC are the Se and Sp in Caret). Any explanations?
pROC
author on here, and it would be nice to get an answer from such a source! // For reasons I cannot recall, I have begun to prefer thePRROC
package topROC
after usingpROC
for years. (I think it’s becausepROC
won’t give $AUC<0.5$, even for awful predictions. I get the rationale, but I’d still like to know what’s happening and not have the software make decisions for me.) $\endgroup$