Unscaling an Standardized pAUC Score

[Adversarian]

Hi, I would like to first start by thanking you for your tremendous work on this library.

I had a question regarding the calculation of partial AUC when a max_fpr value is set (specifically for the binary_auroc case). It was my understanding that when max_fpr is set to for example 0.2, the pAUC is capped at 0.2 as well but during my runs I'm getting values well over the maximum that I expected (in the 0.9s for instance). Then, reading the documentations I see that the module calculates the standardized partial AUC which I'm assuming scales the values into a range where 1 is the maximum again.

My question is how can I scale this back into range where 0.2 is my maximum. Is this as simple as multiplying my current AUC value by 0.2 or are there other things I need to consider first.

Thanks in advance for your guidance.

[Adversarian]

The standardization can be reversed through the formula described here (courtesy of McClish, 1989):
https://www.medcalc.org/manual/roc-curve-partial-area.php