It now appears that “Billyball,” as its advocates called Beane’s statistical approach, doesn’t have quite the track record of success Carey reported. The most famous account of Beane’s method was Michael Lewis 2004 book Moneyball, which looked closely at Beane’s 2002 draft picks, since the Athletics had accumulated an unusually large number of such picks that season. As New York Times sports columnist Murray Chass recently recounted, the Beane’s 2002 choices chronicled in the Lewis book have proven less than felicitous. Statastically speaking, the other teams which picked based on scouting reports did better than the Athletics. You can count us among the skeptics that evaluating teachers is a process akin to judging baseball talent. But it is interesting to know that the baseball model being proffered as a basis for judging teaching performance was not even successful on its own terms.
As people who have actually read the book know, the premise of Moneyball was that Billy Beane was able to exploit inefficiencies in the baseball labor market created by the difference between what people believed was important in a baseball player and what, statistically speaking, was actually important. Some of those biases were between different kinds of statistics--people overvalued stolen bases and undervalued on-base percentage. Other biases were between human observations and statistics--people believed they could identify talent by looking at it, and were often wrong. People also tended to gamble high draft picks on high school pitchers, even though such choices rarely pan out. Beane's approach was particularly valuable to the A's because they were, and are, a small market team with relatively low revenues. Teams like the Yankees could overvalue players and still win a lot of baseball games because they had money to waste. The A's didn't, and so it was critically important to maximize the number of wins per dollar spent. Beane's success in this respect is completely irrefutable; under his management the A's have consistently won more games than most teams while spending less money.
The Murray Chass column Leo references is about one small slice of that overall strategy, the 2002 amateur draft, which forms a lot of the narrative of Lewis' book. Chass' suggestion that the long-term result of that draft doesn't support Beane's strategy is based primarily on the following:
Four of the seven players picked by Oakland (57 percent) among the first 39 picks in that draft have played in the majors, including [Jeremy] Brown. Of the other 32 picks, 20 have played in the majors (62.5 percent).The A's first pick in that draft wasn't until 16th. So their average draft position among the first 39 picks was lower than the average position of the other teams teams. More importantly, that draft was a success. Three of the four players--Nick Swisher, Joe Blanton, and Mark Teahen--have become successful major leaguers, which is a fine rate given the small percentage of draftees who succeed. Chass notes that only one is still with the A's as if that's a negative, which is silly--I don't think any believes the Red Sox were wrong to sign Babe Ruth just because they eventually sold him to the Yankees.
Chass also notes that Prince Fielder, one of the players chosen before the A's first pick, turned out to be quite good. Sure--but most of the other players drafted before the A's first pick, Swisher, didn't do nearly as well. In fact, the first round of the 2002 draft is littered with high school pitchers who went bust because of injury problems--precisely the kind of player Beane rightfully avoided, one of the many reasons the strategy Leo derides has in fact worked so well.
Update: A reader points out that "Billyball" is the term for the way Billy Martin managed the Yankees, not the way Billy Beane runs the A's. Another strike against Leo.
Update 2: Matt Tabor has a good post in response to Leo here.
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