Pagespeed and WPT results - Rule set Matrix?


I made a short attempt at reviewing prior posts but didn’t find my answer. I’ve also spent some time digging through the private instance files to try to tie things together.

I am reviewing documentation from yslow and page speed to set development best practices and threshold limits of certain metrics gathered through yslow and WPT.

Does anyone know where to find a page speed rule set matrix?

One might argue that page speed doesn’t “score” in the same way as yslow but you do get an overall x/100 grade and when you click on the page speed tab and you see the tree view with things that are flagged as red, yellow, or green check… what rule set is reviewing that? What criteria is reviewed to allow some things to be given a green check but also have room for improvement?

Has anyone found a document like this one from yslow linked below for pagespeed? Also… what rule set is applied to WPT when making the scorecard? How are grades for TTFB and browser cache determined? ( This I was able to find but still using it as an example for the rest)

Thanks in advance.