Hi, thanks for the quick response, but as i said in my case due to two different threshold the detected features will differ. Moreover, there is some standard /refined/ formula in calculating the tpr and fpr. herewith i had attached the refined formula from a standard international journal http://r.789695.n4.nabble.com/file/n4640577/tpr_and_fpr.jpg
when i used the above mentioned formula (fpr=fp/fp+tp) then i can able to see my point are distributed on the extreme left corner. Like this it is possible to put all the 6 images. Will you please suggest me now how to obtain the plot for different images of two threshold. -- View this message in context: http://r.789695.n4.nabble.com/no-true-negative-data-need-roc-curve-tp4640474p4640577.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.