Richard, thanks, I think it will work. I will calculate the cutoff value and then, from the prediction object, find the fpr that is related to it and put it as argument to performance. I will keep you informed.
Eleni On Wed, Mar 19, 2008 at 11:51 AM, Richard Pearson < [EMAIL PROTECTED]> wrote: > Eleni > > Does the fpr.stop argument do what you want? This is described in > ?performance under the details of the "auc" measure. Try, e.g. > > perform=performance(pred,measure="auc",fpr.stop=0.5) > > > Richard. > > > Eleni Christodoulou wrote: > > Hello list, > > > > I am trying to perform ROC analysis and count the AUC in order to > validate > > my results. I use package ROCR. I would like to count the AUC not under > the > > cutoff found by "performance" but to use another cutoff that I > calculate. > > How could I change the following command in order to get what I want? > > perform=performance(pred,measure="auc",x.measure="cutoff"), where pred > is a > > prediction object. > > > > Thank you very much, > > Eleni > > > > [[alternative HTML version deleted]] > > > > ______________________________________________ > > R-help@r-project.org mailing list > > https://stat.ethz.ch/mailman/listinfo/r-help > > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > > and provide commented, minimal, self-contained, reproducible code. > > > > > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
