I am working on an application to evaluate the performance of SVM on a number of different datasets.
SVM is working well, yielding 98% diagonal accuracy.
I now need to evaluate the performance of this model, so using ROCR library, I plotted the ROC, err & acc curves.
The ROC is displayed as the False Positive Rate vs. True Positive Rate, and for the error & accuracy curves, these are plotted against an element called cutoff.
Could someone explain what this cutoff is exactly? (Needless to say, I am relatively new to this subject)
Thanks in advance