Someone asked me where I got the following guidance for Area Under the Curve (AUC) for a Receiver Operating Characteristic (ROC) curve.

- 0.50 to 0.75 = fair
- 0.75 to 0.92 = good
- 0.92 to 0.97 = very good
- 0.97 to 1.00 = excellent.
I cannot find where I got these numbers. It must be a sign of senility on my part. I’ll keep looking, but if anyone else knows of justification for this or any other rule, let me know.

I did find a web page (gim.unmc.edu/dxtests/roc3.htm) that suggested this rule

- .90-1 = excellent (A)
- .80-.90 = good (B)
- .70-.80 = fair (C)
- .60-.70 = poor (D)
- .50-.60 = fail (F)
but the evenness of the intervals strikes me as rather arbitrary. I’ll keep looking.

You can find an earlier version of this page on my original website.