summary ROC curves

summary ROC curves

by Tu My -

Question regarding the SROC curve on slide 33 for lecture #4 (this week's lecture):

I was under the impression that ROC curves should start at (0,0) and end at (1,1). However, on this graph we see that the two curves depicted will end at different places. Is this due to the nature of the data being presented (i.e. a summary of studies)? Are the curves 'true' ROC curves?

Thanks!

 

Re: summary ROC curves

by Thomas Newman -

Great question!  I will answer in class Thurs, but short answer is that you are right to think there is something very fishy about the worse of the 2 ROC curves.  ROC curves should always go through 0,0 and 1,1.

Tom