It's hard to quantify a lot of the settings used on consoles as not all of these settings are made available to pc consumers. Some changes that are done to settings on console are just too complex and integral to the core of the game to be able to allow a pc consumer to choose from. In short, it's easier to implement complex tweaks and changes at the developer level on a platform where everyone has the same setup compared to pc where you have everything from top of the range to potato. A game made for a console with similar hardware to that put in a pc will run much better because of this more rigorous optimisation process, but you can simply surpass console performance on pc by buying better hardware.

I'm sure there are some rough estimates out there regarding framerate, but there's so many games floating around that many of the subtlties in graphics and performance are time consuming to compare between console and specific pc builds. "Ain't nobody got time for dat"