So I hope you're aware by now of the High Heat Stats blog, which is basically what the Baseball Reference blog used to be, but is no longer hosted at BB-Ref.
They've done a fun couple posts lately, attempting to list the 50 most overrated and then most underrated hitters in baseball history (today, they're starting on the pitchers). Being specifically a stats blog, of course, they were pretty limited in the ways they could come up with to arrive at lists like that. I think the one they devised (with the help of the excellent Sky Kalkman) was pretty brilliant.
Basically: use the player's career rWAR as a proxy for his true worth/value/talent/etc. Then take BB-Ref's EloRater -- a system which gauges where the thousands of BB-Ref users rate each player -- as a measure of how the fans view the player. Then, figure out an expected WAR (eWAR), representing the career rWAR we'd assume a player would have if his production merited the rating he gets on the EloRater, based on the players surrounding him in the EloRater rankings. So, the players with the highest eWAR-rWAR are your most overrated players, and the ones with the highest rWAR-eWAR are your underrateds.
Ingenious...but not necessarily perfectly attuned to tell you what the headlines promise (which they happily recognize, and I'm not sure any stat or collection of stats could do that). Some of the guys who show up on the "overrated" list spent time in the Negro Leagues, or were otherwise prevented from putting up a career rWAR that accurately reflects their worth; most of the underrated list ends up being nineteenth-century guys, whose "replacement level" was likely much, much lower than the current ones. They're interesting lists, but they don't necessarily reflect the most under- and overrated players in baseball history.
I want to focus on two names in particular, though, from the overrated list: Ted Williams and Joe DiMaggio.
