(question about biometrics) What is the difference between these ROC curves?

Hello,

I am reading something about ROC curve. And I found that the curve is different given in different publications. So, I am a little confused, and I found these curves with Google. But I am wondering why they are different? And how can I know which area is the AUC (area under curve) for different ROC plot?

Thanks.

Answer 1

[Image Analyst]

I always see ROC curves like your middle one. That's like the one in Wikipedia. Perhaps some people have plotted things differently for some reason that they gave in their papers - I don't know since I didn't read their papers. I think the area under the curve would be calculated by summing the curve values when plotted linearly, not on a log plot.

[ZhG]

Do you mean that the 1st one is only log plot, otherwise it would be the same to the one in the middle?

[Image Analyst]

I think FRR must be different than True Positives because the curves bend in the opposite direction. Normally for algorithms that are good at detecting, the curve bends up and to the left.