Thursday, November 16, 2006

Past A Diving...

One of the constant refrains of the season past was about the World Class Crappiness of the team's defense. Especially in the middle infield, it was a complete nightmare, and had a major hand in turning a crappy pitching staff into a fan-morale-killing torment that would've been comical to watch if 1) I didn't have a rooting interest and 2) I hadn't paid actual money to watch it.

Evaluating defense is sort of the Holy Grail of sabermetrics. Everyone and their brother has their own method of figuring out how much a player's bat is worth -- most of which come within just a few runs of each other. But defensive stats are all over the place. Even using similar data, different systems can produce contradictory results. Earlier this year, I took a look at a few of those stats, trying to describe what they do, and what they told about the Nats. (Short answer: we suck)

One of the ones I didn't look at was the Probabilistic Model of Range. (catchy name, huh?) David Pinto, at Baseball Musings, has been working on a method of evaluating defense, using play-by-play data to figure out what a team should be doing. His method is here, but, in short, he looks at a number of factors including direction of the ball, speed of the ball, handedness of the pitcher and batter, etc, to determine what the odds are that the fielder can make the play. A soft flare right to the shortstop needs to be caught 100% of the time. A screaming liner back through the box will be turned into an out much less frequently. His database scans through all the plays assigning a value to the team's defense.

And, well, for the Nats, it stinks. In the overall team results, the Nats are dead last. Based on this method, the Nats should have recorded 3,220 outs on balls put in play. They only got 3173 outs, a difference of about 50 outs. In the abstract, that's 2 entire games worth of outs that they crapped away whether by error or a complete lack of range. Looking it another way, the defense caused the pitching staff to throw at least 17 more innings than it needed to -- and likely higher because innings continued, in many cases, beyond where they should've ended.

When an opponent put a ball in play against the Nats (ie: not a walk, K or homer), they batted .309. They should have only batted .299. Bad defense contributed 10 points of batting average. Scary!

Pinto, helpfully breaks the team stats down further, into infield and outfield expectations.

In the outfield, the Nats were squarely in the middle of the pack, turning about as many balls into outs as you'd expect -- just a difference of three outs. Austin Kearns is a terrific defender. Soriano had some growing pains, but his assists made up for some misplays, and he was pretty good by the end. The jury's out on Church. I don't think he's great, but he didn't seem as bad as someone like Preston Wilson.

So about the infield, the killing field. The Nats, as you'd suspect were the worst in the league, and groundballs accounted for roughly 50 should've-been outs. Nats infielders let opposing batters, when they put the ball in play, bat 25 points higher than they would've with just an average defense. The difference between the Nats and the best team, the Astros (with Adam Everett, a shortstop that most stats say is an All-Time great fielder), is mind-blowing, roughly 50 points of Batting Average in balls in play. It's depressing to think about, especially with the prospect of those same 'fielders' running back out there next year.

I've always been of the mind that defense was underrated by most statheads. You only need to go back a few years ago to see Baseball Prospectus writing articles praising the late-90s Oakland A's for completely punting defense. (Jason Giambi, outfielder!) But with the recent rise in prominence of DIPS and Batting average on balls in play, the role of defense seems to be gaining in prominence. Oakland, for example, seems to emphasize that more than anything, even as hacktastic scribes still rant about OBP and Moneyball. Meanwhile, over the last two years, Chicago and Detroit have made it to the World Series, in large part because of their outstanding defense. (Save your pitcher's errors jokes for another time!)

USS Mariner recently had a somewhat-maligned post about Aramis Ramirez, contending that Aramis (he of the 35+ homers a year) is basically worth as much as Adrian Beltre (he of the mediocre offensive numbers). It's a convincing case that rests partially on the park, but mostly on the defense. The spread between an average defender and the best in the league might not be as large as the same for offense. But the spread between the best defenders and the worst is quite large -- as the Houston example above demonstrates.

Putting together a team isn't just about putting runs on the board, but keeping them off as well. Now that's not to say that the Guzman/Vidro decision is a slam dunk for Guzman because of the defense. The chasm between their offensive values is important.

But turning a ball in play into an out is essential, especially for our maligned pitchers. And it's something the Nats failed at, quite miserably.

12 Comments:

Post a Comment

<< Home