Sunday, May 14, 2006
Any good baseball argument invokes the use of statistics, whether to compare the relative merits of two players or the worthiness of an aspiring Hall of Famer. But while 20-win or 30-home run seasons are clear benchmarks for pitchers or hitters, no such equivalent exists for defensive ability.
Are such skills measurable? Author John Dewan has come closer than anyone else to quantifying defense in his book "The Fielding Bible," but some skeptics suggest Dewan -- with an assist from noted stats guru Bill James, Dewan's business partner and friend -- has just tried to do something that can't be done.
"For over 100 years," Dewan said in a recent telephone interview, "all we had [to measure defense] was putouts, assists and fielding percentage."
Dewan's company, Baseball Info Solutions, employs "video scouts" who review every major league game, charting every batted ball and recording its direction, location, speed, type (line drive, fly ball, etc.) and result. Given any combination of those factors, a computer can spit out how frequently such a play is made by the average major leaguer at that position.
"For example," Dewan said, "vector 17 extends from home plate to a spot between shortstop and third base. On a softly hit ball to that location, the average shortstop makes that play 26 percent of the time."
Using averages such as those, Dewan's system assigns a "plus" or "minus" on every play -- the more difficult the play, the more plus credit is given if it is made. And at the end of the year, he totals up the pluses and minuses to arrive at a player's plus-minus figure.
Some of the results are not surprising. Alfonso Soriano, for example, achieved a rating of minus-40 over the previous three years as a second baseman -- meaning he made 40 fewer plays than the average second baseman -- which ranked next-to-last behind only Bret Boone.
However, other conclusions reached by "The Fielding Bible" are the equivalent of fighting words.
James, for instance, spends 4 1/2 pages near the front of the book explaining why Houston's Adam Everett is a far superior shortstop to Derek Jeter. In fact, Jeter, according to James, was "probably the least effective defensive player in the major leagues, at any position" over the last three years.
This is where baseball people begin to have problems with Dewan's book -- and for that matter, with the entire notion that defense is wholly quantifiable.
"The problem with statistical analysis on defense is that it can't give you the breakdown of a guy who is the better ninth inning guy," said one AL scout. "Do [the Yankees] want the ball hit to A-Rod [Alex Rodriguez] in the ninth inning even though he's the better fielder? No, you want it hit to Jeter, even though the numbers say he's not as good. . . . It's something you can't quantify."
Although Dewan's company sells information to "more than a dozen" big league teams -- including "a handful" who purchase the defensive information -- the Detroit Tigers are among the teams that passed after seeing the sales pitch. According to GM Dave Dombrowski, the numbers are still not as valuable as the conclusions that can be drawn from good, old-fashioned scouting.
"Some people think you can [quantify defense]. I don't really buy that myself," Dombrowski said. "I've looked at some of those new formulas. I'm not sure I would believe everything I've seen there. It's one of those things where, if you study [the players] yourself, you can have a better feel for those things than any numbers can tell you."