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I have read many articles about roc curve and how it works. But im still confused. Can someone please explain me what the points 5, 7, 9 means in the picture below?

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marked as duplicate by Dilip Sarwate, Tim Mar 1 '18 at 14:02

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  • $\begingroup$ What is it that you don't understand? There are many possible explanations out there, but some don't seem to work for you. It would be helpful if you could narrow down your question. $\endgroup$ – KenHBS Mar 1 '18 at 13:22
  • $\begingroup$ You will see a lot of confusion about when to make an ROC curve. To oversimplify, it is used for group decision making and has nothing to do with individual decision making, the latter being almost always what we want. $\endgroup$ – Frank Harrell Mar 2 '18 at 15:29

I assume you took that figure from this website: http://gim.unmc.edu/dxtests/roc2.htm

If you look at the table next to the figure, you can see that each value of the variable T4 is associated with a proportion of true positives (TP) and a proportion of false positives (FP). The ROC curve is simply a graph of TP against FP, where every pair (FP, TP) is calculated from a value of T4.


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