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. Evaluating the AUC for an ROC curve