You see, every time a rookie shows up in the majors (and often before that, even), he’s assigned a unique ID by each of the fantasy league hosts. When Yankee’s “phenom” Anthony Claggett was called up earlier this year, Yahoo ID’ed him as number 8450, CBS assigned him 1654377, and ESPN determined that he would be player 2312.

And since they all use different IDs to refer to the same player, it has been my job to match those up. For every player.

Luckily, I was able to start out from some pretty good sources. Tango compiled IDs from several different sources for players who played in 2008. Benchcoach had quite a few that he didn’t have. With assistance from some helpful individuals, as well, I’ve managed to build a pretty decent list of player IDs.

Right now I have about 10,000 players with IDs from STATS (used by Yahoo and Allstar Stats), MLBAM, ESPN, CBS, BIS, BDB (Baseball-Reference), and Retrosheet. I’ve also tried to keep track of name variations between sources. There are still lots of gaps, however, as I only have a complete set of IDs for about 12% of those players.

Just in case anyone is interested in what I’ve got so far, though, here’s the full list:

ID Conversion (May 01, 2009)

Much of what is discussed here will involve the Price Guide, an online tool I developed to build dollar values or player rankings customized for any league configuration.