I am doing an experiments where changing a parameter I am obtaining different number of FalsePositive, FalseNegative... and so on. I am using this parameter tuning as threshold tuning to obtain FPR and TPR to build a ROC curve. However, the problem is so easy tha it gets most of the time the point near [1,0]. I never have any point near [1,1]. If I want to compute the AUC, what am I supposed to do? To add artificially a point [1,1]?
Moreover, for another experiment I have some values of TPR and FPR which are disproportionated to other cases, and they look weird.
Thank you. Now I am using directly probabilities from the classifier. However, I am still not getting to the point [1,1].