The subject of defense is a hotly debated one in baseball analytic circles. For years we were stuck with just errors and thusly judging fielders on their ability to cleanly field batted balls. As statistical analysis has progressed, so has the measurement of defensive ability. These new defensive metrics — UZR, ZR, the plus-minus system — are interesting to consider, but they don’t give us the same level of insight as offensive and pitching stats. Yet they are interesting because they are not perfect. We’re still trying to figure out the best way to measure defense, and imperfect stats make great conversation starters.
Last week we discussed some Yankee-related issues from The Fielding Bible Volume II, John Dewan’s updated effort at pegging defensive ability. Using stats, articles, and scouting reports from the book, I was able to piece together articles on Robinson Cano’s range and Derek Jeter’s clean fielding skills, but those clearly aren’t the only cases you can make after reading through the 400-page tome. It contains all sorts of stats and leader boards that can provide varying levels of insight on defensive ability.
The volume can keep a fan occupied for days, even weeks. It’s filled to the brim with data, from raw numbers to processed stats. Dewan rates fielders on all sorts of criteria, and most of it is presented in these pages. How well they ranged to their left and right, how they turned the double play, how they fielded when playing shallow, deep…it’s a truly comprehensive look at a player’s fielding ability. Even if you want to know how many outs a player recorded in 2008, The Fielding Bible has that.
One of the most interesting parts of the book, which we didn’t get to touch on in the Jeter and Cano discussions, is the Defensive Positioning Chart. As Dewan notes, these are not spray charts. Rather, they represent the distribution of hits which can be reasonably turned into outs. That, of course, requires a level of subjective judgment, a complaint I’ll address in a minute. For now, let us revel in these colorful charts which depict a player’s hitting tendencies. One of my favorite charts is of Joey Gathright. The charts make a case for an Ortiz-like shift for the speedster, but to the opposite side. He almost never hits the ball down the first base line either to the infield or outfield. (The problem, of course, is that he’s so fast that the first baseman can’t stray too far off the bag.) According to the chart, if a manager plays his second baseman pinching towards second, his shortstop playing slightly toward second, his third baseman slightly to the left of normal, his left and center fielders shallow, and his right fielder well off the line, he should be able to contain Gathright considerably. It’s really neat stuff both from an analytical and visual perspective (The colors, children! look at the colors!).
Another amazing aspect of the book is the six-year register. As the name implies, this section contains data for nearly every Major Leaguer over the past six seasons. As Dewan explains it, this helps mete out poor single years in favor of a more comprehensive, thus more accurate, view of the player. For instance, he says, Mark Teixeira had a pretty poor season with the glove in 2007, but when you look at his six-year marks he still emerges as one of the best first basemen in the league. This is one aspect which will help advance the accuracy of defensive statistics. We’ve only started to seriously measure them recently. Larger samples will do wonders for analysis.
The book isn’t without its faults. While Bill James’s chapter on Defensive Misplays and Fielding Good Plays was interesting, he’s still using some subjective judgments. That’s not wrong in itself — we make subjective judgments about baseball every day and sometimes we’re right — but when the goal is an objective system to judge a fielder’s ability to make a clean play, any hint of subjectivism detracts from the case. Still, I like the idea of stripping defensive misplays (the act of misplaying a baseball, not James’s stat) of as much subjective judgment as possible. We all have our own ideas of what “ought to have happened,” meaning five people making the judgment could call it differently. As such, we either need to qualify those who do make the judgment, or else need to strip the subjectivity out as much as possible. James’s effort is certainly commendable, and I hope in the future he’ll not only release a more comprehensive list of his results, but also go deeper into his methodologies.
Through the efforts of curious minds like Bill James, the baseball analysis community has evolved over the past three decades. We now have not only a better idea of which basic stats tell us a better story about a player (OBP, SLG), but some great minds have developed advanced statistics which put them into an even greater context (wOBA, EqA, VORP). Similar efforts have been made to harness pitching stats. We’ve learned that pitchers have little control over what happens to a batted ball, hence the focus on peripherals like strikeouts, walks, ground balls, and line drives. These help us not only determine which pitchers have better and more sustainable abilities, but also to help us construct a more complete story of the player. The hope is that over the next few years we make this kind of breakthrough with defensive stats. So observe, analyze, criticize, scrutinize. It’s how we come to new conclusions about previously unknown issues.
You can get The Fielding Bible–Volume II
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