ブルペンの研究

The Hardball Times 1/12/05 Team Bullpens
http://www.hardballtimes.com/main/article/team-bullpens/

Over at Baseball Prospectus, they keep track of something called Win Expectancy Added for every major league reliever, which I assume is based on the same principle as Win Probability (covered in a previous article). Win Probability/Expectancy Added is a great way to evaluate relievers, because it measures their impact on the game (which is what relievers are really paid to do) by looking at how well they pitch AND how critical their appearances are during the game.

2004 Reliever Expected Wins Added Report
http://www.baseballprospectus.com/statistics/rel_winexp2004.html
大塚が全メジャーの第6位に評価されている。
参考
Business Week 11/5/03 What's a Ball Player Worth? Two game-theory experts have developed a model they claim can tell the champs from the chumps. And they're getting a chance to prove it
http://www.businessweek.com/print/bwdaily/dnflash/nov2003/nf2003115_2313_db016.htm?db
The Hardball Times 12/27/04 The One About Win Probability
http://www.hardballtimes.com/main/article/the-one-about-win-probability/

As I said, it goes by many names: "Player Win Averages" (Mills brothers), "Player Game Percentage" (Bennett), "Win Probability Added" (Drinen), "Win Expectancy" (Tangotiger), "Game State Wins" (Rhoids website), "Player's Win Value" (Ed Oswalt) and WRAP (Lonergan and Polak). I'm sure there are other people who have done the same thing and given it a name that I've not acknowledged here. I apologize if you're one of those people. For purposes of this article, I'm going to use the Drinen name, "Win Probability," because I think it's the most descriptive.