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"What the heck is DER, and why should I care?" -- CLUELESS IN SEATTLE DEAR CLUELESS, DER is short for Defensive Efficiency Rate. Baseball Prospectus gives the full definition: Defensive Efficiency, is the rate at which balls put into play are converted into outs by a team's defense. Def Eff can be approximated with (1 - BABIP), if all you have is BABIP, but a team's actual Def Eff is computed with 1 - ((H + ROE - HR) / (PA - BB - SO - HBP - HR)). Simply put - this measures how often a team defense turns a ball in play into an out - the ratio of defensive outs to defensive chances. Typically, a ball in play, (but not a homerun), is turned into an out about 68.7% of the time. The median DER in recent years has been around .687. Errors complicate matters, because errors are not counted as hits or outs. So, while batting-average-ball-in-play (BABIP) is typically around .300. This is why the note from BP above says that 1-BABIP is an approximation. And pitchers have a higher out rate, so there is a minor skew between AL and NL. As to why you should care -- while the statheads have made great headway in regards to creating a spate of solid metrics for assessing offensive performance, which are accurate and to a degree, predictive, defensive metrics in baseball are today a hodgepodge of differing opinions, propietary inputs, and headache inducing formulae. DER has value because it is simple and easy to understand. If you hit a thousand balls at this or that defense, it'll turn 687 ... or 712 ... or 670 into outs. Flipped over, it's basically the opponents batting average with HRs and strikeouts removed. In 2008, Seattle ranked 26th in baseball in DER (.682), meaning opponents hit about .318 against the Seattle defense. Tampa had a .710 DER, meaning opponents hit about .290 against their defense. And, in case you're wondering, back in that magical 2001 season --- Seattle was #1 in baseball with a .727 DER, (St. Louis was next at .704). ================= DEAR SANDY, "If we stink so bad in DER, will it take forever to improve?" -- RESTLESS IN SEATTLE DEAR RESTLESS, Not at all. In point of fact, there have been several cases in recent history where a team has had a drastic shift in their DER results in a single season, including a literal worst to first jump in 2008:
Tampa 2007 = .656 (30th) -- 2008 = .710 (1st) Each of these teams had player changes in one or more of the up-the-middle positions, (2B, SS, CF). But, otherwise the lineups were often predominantly static. It is hard to imagine these changes making THAT much of a difference by themselves, (especially given stellar reputations of some of the players replaced). The analysis of *WHY* these defenses improved so drastically is very debateable. This is meant only to note that drastic changes in DER can (and do) happen on a regular basis. =============== DEAR SANDY, "Is it true that if our pitching and hitting are good enough, DER doesn't matter?" -- SKEPTICAL IN SEATTLE DEAR SKEPTICAL, Actually, I think it is VERY difficult to have "good pitching" without good defense. That 2007 Tampa pitching staff was #1 in the AL in strikeouts - (1194). They were DEAD LAST in ERA (5.53) and runs allowed (944). Some would point to the horrible ranking in walks (11th - 568) and HRs (14th -- 199), as evidence that the pitching wasn't actually good. But in 2008, they had fewer Ks, (1143 to rank 4th), cut down slightly on the walks (526 to rank 8th) and cut down slightly on the HRs (166 to rank 9th). The team, however, finished 2nd in hits allowed, and 2nd in ERA and runs allowed. Look at the movements: Ks - a decline of 51. HRs - a decline of 33. Walks - a decline of 42. What happened to the hits total? A decline of 300 (1649 to 1349). You ask any thousand baseball fans and pundits about the 2008 Tampa Bay Rays and they will laud how their PITCHING really came together. They will point to Kazmir and Shields coming of age. They will ignore the fact that Kazmir and Shields both struck out fewer hitters. They will attempt to credit the worst to first change on the pitching side -- 33 HRs and 42 walks removed. If I attemp to attribute their success to the defensive impact of Jason Bartlett at short, and B.J. Upton taking over in CF, I would just induce raucous laughter. One can debate WHY the defense improved. What is undeniable is that the team allowed 300 fewer hits from 2007 to 2008. To get that kind of reduction from pitching alone would likely require about 900 additional strikeouts. I'm sure that last statement will be viewed as hyperbole. It's not. The reason why is that a strikeout does NOT prevent a hit. A strikeout prevents a BALL IN PLAY. Well, we know that roughly 2/3 of all BIPs end up as outs anyway. So, a rough guideline is that pitching prevents a hit with roughly every third strikeout. If you wanted to reduce the number of hits allowed between two seasons (all other variables remaining the same), then you would need to strike out roughly 900 more batters. Most people don't bother to think about these things. You see Paul MaHolm with 139-K in 206 innings, and you yawn. You see A.J Burnett with 231-K in 221 innings, you think one of the best in the game. Nobody bothers to LOOK at the hit column for pitchers. If you did, you'd see 211 hits allowed by Burnett and 201 allowed by Maholm. This is not intended to infer that Maholm is as good a pitcher as Burnett. The point is to try and illuminate just how important the hits-allowed column happens to be for pitchers -- and to stress that this is why team defense is so critical. Toronto actually had one of the best defenses in baseball in 2008, and for whatever reason Burnett did not benefit as much from it as his teammates. When you adjust for the difference between AL and NL, the two pitchers ended 2008 as nearly identical in ERA despite Burnett getting 92 more Ks. In regards to the importance of DER to a team, this does not mean that an exception is impossible. In any given division, SOMEBODY has to finish first, and depending on the variables in play, (especially with dreadful competition), a team can succeed with any number of deficiencies, so long as they are less deficient than the competition. Oakland in 2004 "should" have won the division, (falling short by a single game), since Oakland managed a 102/109 OPS/ERA+ split, while Anaheim went 103/105. Oakland had the superior defense, and Anaheim ended up ranked 24th in DER, (Oakland 9th). Anaheim struck out 130 more batters, and still allowed 10 more hits. But Oakland did a poor job of translating its OPS and ERA into runs and run prevention. The truth is that if you get good enough at ANYTHING, then the other parts of the game become less critical. If you have a team that can score 1000 runs in a season, good pitching and defense cease to be "critical". If you only allow 600 runs in a season, then the need for a high team OPS drops. It's possible to overcome a bad DER -- but to do so not only requires a LOT of strikeouts, (which reduce the number of balls to be fielded), but you also have to limit the walks and HRs drastically as well. ================ DEAR SANDY, "So, you want the Ms to invest in DER. What should I be investing my money in?" -- BROKERLESS IN SEATTLE DEAR BROKERLESS, I would suggest investing in companies the actually provide good or services that people want and can use. Stay away from investing in areas where the logic is simply that someone else will happen along tomorrow willing to pay more money for the exact same item. This, IMO, was the foundation flaw of the housing bubble: America had bought the bill of goods that a house bought today was "GUARANTEED" to sell for more tomorrow. House prices appreciate reasonably against inflation. That makes sense. House prices appreciate because the demand in a specific area exceeds the supply. So, houses that exist in the best parts of town logically become worth more. But the market forgot WHY houses appreciate, and instead simply took the position that ALL houses appreciate, so any and every house bought today would have a buyer tomorrow willing to pay double, (and you wouldn't even have to add a bonus room). But mostly, I would say -- invest in yourself. Take a class. Learn a new skill. Find a hobby that brings you pleasure, and perhaps even allows you to produce something somebody else may want. Maybe it pays off financially in the long run, maybe not. But, if it brings you joy today, you're already getting a healthy return on investment. |