what does optimistic AUC mean ROC curve ?

funnyhat

I still can not get the concept of AUC, optimistic AUC, pressive AUC. And I can not find explaination anywhere,  I noticed that for some operators, these three are same, but for some else, such as WEKA bayes net, there are totally different, then for model comparation, which AUC should I use to compared with ?

Besides, I really dislike the ROC curve from rapidminer, I hope some simple ROC (or ROC comparation)curve without plus/minus and in publishable quanlity, can I have such option somewhere when I generate ROC? another option is that I transfer out the ROC data to eg R, and plot ROC there, I hope that is not the idea of ROC curve.