Derek Jeter vs. Objective Reality
Why baseball researchers are obsessed with denigrating the Yankee captain's defense.
Derek Jeter is quite good at playing baseball. As such, he'll earn north of $30 million this year in salary and endorsements. Despite a poor offensive season by his standards, fans voted Jeter to his ninth All-Star team, where he will start at shortstop for the American League on Tuesday night. Add to that his four World Series rings and dalliances with actresses and beauty queens, and there is a lot to recommend the Yankees star. There's just one small blot on his résumé: When it comes to playing defense, Jeter sucks.
In February, Shane T. Jensen of the Wharton School unveiled a paper on a new method for evaluating defense in baseball. The take-away from the study, which was presented at the annual meeting of the American Association for the Advancement of Science, was that Mr. Jeter (despite his three Gold Gloves and balletic leaping throws) is the worst-fielding shortstop in the game. The reaction in the New York media was predictably apoplectic. The New York Post's headline: "You've Got to Be Kidding!" The reaction from baseball's vast community of statistical analysts: a collective yawn.
One reason why baseball statisticians didn't get too excited about the study is that Jensen's methods ("for each grounder ball-in-play—g-bip—we have the—x,y—coordinates in the field where the g-bip was fielded" and on and on) are grounded in the familiar language of the sabermetric literature. Mostly, though, the paper didn't provoke much intrigue because Jeter's badness is already an axiom of said literature. In fact, debunking the conventional wisdom about the Yankee captain's fielding prowess has become a standard method of proving the validity of a new fielding statistic. That places Derek Jeter at the frontier of new baseball research.
Articles in the "Jeter sucks" canon include: James Click's "Did Derek Jeter Deserve the Gold Glove?" from the book Baseball Between the Numbers, Tom Tango's "With or Without Derek Jeter"from the Hardball Times Baseball Annual 2008, Bill James' "Jeter vs. [Adam] Everett" from John Dewan's The Fielding Bible, and Mike Emeigh's "Derek Jeter and the State of Fielding Analysis in Sabermetrics, Parts 1 Through 8"(really). The gist of all these articles is that Jeter generally makes the plays he gets to (in fact, it turns out he's slightly better than most shortstops at charging slow ground balls and handling balls hit right at him), but he gets to many, many fewer than he should. As fielding-stat pioneer Michael Humphreys * explained it to me, "Basically, he's OK at easy plays and terrible on all others, in other words, all the plays that matter." That patented jumping, twisting throw to first? Probably just a byproduct of his limited range. As the Onion once declared, "Experts: Jeter Probably Didn't Need To Jump To Throw That Guy Out."
If the sabermetric case against Jeter's glove has long been closed, why do the sabermetricians keep opening it? In an e-mail, Tom Tango joked that Jeter comes up again and again "because he gets far more girls than his fielding talents should allow." And there's probably something to that: The stat guys want to kick a little sand back at the press-box bullies—all of whom seem to have Word macros for phrases like "nerd writing in his mother's basement"—who lazily swallow the myth of Jeter's fielding prowess.
But the better answer is that Jeter's defense is at the heart of the conflict between sabermetrics and traditional baseball fandom. A recent article by Baseball Prospectus' Dan Fox poses the age-old question, "[W]hat would Sir Francis Bacon, the English philosopher and statesman, have thought of Jeter's defense?" Fox, who recently announced his departure from the blog world to join the front office of the Pittsburgh Pirates, looks back to Bacon's notion that people tend to think that memorable incidents define the whole. So we see Jeter flip the ball to Posada or emerge bloodied after leaping into the stands to catch a Trot Nixon foul ball and think "great fielder." Bacon, like today's statistical innovators, would seek out objective scientific data to understand the larger truth about Mr. Jeter. These data show that—yes, Sox fans—Jeter totally sucks.
Derek Jeter has the (small) misfortune of playing in the first era when there are objective data about fielding. In the introduction to The Fielding Bible, BillJames points out that your standard array of batting and pitching statistics gives a decent sense of a player's skill level. That's not the case with defensive stats. Anyone who's ever yelled "You call that a hit?!?" understands the subjective nature of error rulings. Besides, the game's standard defensive statistic, fielding percentage, only tells us how a fielder deals with the balls he ends up reaching. They tell us nothing about how well a player moves through space—how he tracks fly balls, how good he is at charging bunts, whether he dives a lot because he has great range or because he doesn't react quickly enough to the ball off the bat. More sophisticated defensive statistics will not only give fans a better understanding of how the game is played. In the age of Moneyball, the teams that figure out how defense works will have seized one of the game's best remaining arbitrage opportunities.
Stat-heads and forward-thinking team executives now have several advanced fielding metrics to parse: fielding win shares, fielding runs, fielding runs above replacement, zone rating, range factor, probabilistic model of range, the Wharton guy's SAFE method (that's "special aggregate fielding evaluation"), and many more. There are so many fielding stats now because the sabermetric community has worked together on the scrivenerlike grunt work of generating useful data. Private-sector companies like Baseball Info Solutions and Stats Inc. have done most of the heavy lifting. They watch every play of every major league game and record the things (trajectory, speed, whether a ball was bobbled or fielded cleanly) that go into defense, then package the numbers and license them to baseball front offices and a few dedicated, independent stat guys. The cost of this proprietary data has not necessarily kept the stat masses from making important contributions to fielding knowledge. It has meant, however, that the best systems are the ones that are most dependent on crunching complicated numbers that don't get updated every day. We're nowhere near being able to check the box score after a game to see how a bad day in the field affects, say, Julio Lugo's ultimate zone rating.
But that day will come. The question is, does it matter to Derek Jeter? Yes and no. There's a better chance that long-deceased Hall of Fame second baseman Nap Lajoie will catch for the Arizona Diamondbacks than that Joe Morgan will cite Jeter's probabilistic model of range stats when explaining how a play unfolded. Until defensive numbers have the same score-at-home simplicity of ERA or batting average, Jeter's reputation is probably safe (as long as he keeps his error totals down). Yankee fans, sponsors, Hall of Fame voters, the ladies, etc., will continue to love him and vote him on to the All-Star team. He will continue to win games, big paychecks, and maybe rings with his bat and despite his glove. But one would hope that the era in which a Derek Jeter can win a Gold Glove will end, and soon, even if it does look cool when he makes those jumping throws to first base.