Yeah, not sure. I know Yahoo's numbers are kind of weird, they keep up preseason rankings (which themselves are just guesses) in weird places for some reason, too. I doubt they're league-specific, either.
That said, they can definitely do some pretty straightforward math on how much a player contributed relative to a) their position and b) the league as a whole that year, which I think is what the Player Rater does.
That said, they can definitely do some pretty straightforward math on how much a player contributed relative to a) their position and b) the league as a whole that year, which I think is what the Player Rater does.