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BABIP/DER

PostPosted: Fri Apr 28, 2006 3:05 am
by The Guru
Can someone go into detail about those 2 stats. I am not completly sure what they mean.

BABIP - I know this has to do with hitters
DER - I know this has to do with pitchers

Whats the league average BABIP number?
Whats the league average DER number?

PostPosted: Fri Apr 28, 2006 10:39 am
by jmk.nyc
Batting Average on Balls in Play. This is a measure of the number of batted balls that safely fall in for a hit (not including home runs). The exact formula we use is (H-HR)/(AB-K-HR) This is similar to DER, but from the batter's perspective.

Defense Efficiency Ratio. The percent of times a batted ball is turned into an out by the teams’ fielders, not including home runs. The exact formula we use is (BFP-H-K-BB-HBP-0.6*E)/(BFP-HR-K-BB-HBP). This is similar to BABIP, but from the defensive team's perspective. Please note that DER for individual pitchers doesn't include errors.

from http://www.hardballtimes.com/main/statpages/glossary/

Sorry I can't go into more detail. :-o BABIP seems to measure the ability of a hitter to hit safely on non-HR contact and the converse for DER.

PostPosted: Fri Apr 28, 2006 12:46 pm
by The Jury
I believe the league average for BABIP is .300, so the average DER would be .700.

PostPosted: Fri Apr 28, 2006 3:28 pm
by The Guru
Here's what I don't understand in this example.

Mike Young BABIP
05 = .355
04 = .335

In 06 his BABIP so far is = .436

Baseball Prospectus says the league average for BABIP is .290.

Here is wht I don't understand: So is Young likely to go from .436 to the league average by years end or is he likely to go near his career average in BABIP?

Since BABIP is balls in play - wouldn't certain speed hitters have a higher BABIP then say slower power hitters since they can tend to run out ground balls with there speed that a slower player can't? Someone like a Reyes, Crawford, Ichiro. Compared to a Aramis Ramirez, Thome, Giambi

PostPosted: Fri Apr 28, 2006 3:40 pm
by George_Foreman
BABIP isn't .300 on average for all ball players. That's just a good benchmark. When you want to find out if a player is getting "lucky" or "unlucky", you should compare his BABIP to his career BABIP. Some players are just faster or get better wood on the ball or whatever.

I'm not sure if minor league stats can be compared to major league ones for BABIP, but I think it would be a reasonable comparisson.

PostPosted: Fri Apr 28, 2006 7:26 pm
by George_Foreman
Nerfherders wrote:Doubles and triples factor into this as well. For the most part, a double or triple has no chance to be fielded. Players who hit the ball hard to the alleys or down the lines will have their BABIP higher than those who hit fly balls or ground balls. I've never really watched Young play much but based on his numbers - .450+ SLG without alot of HR - I would say he is that type of player.
Not really true. A "double" could also be an "F7" if the left fielder is shading over in the right direction or a "single" if its hit to someone with a really strong arm. There's nothing inherent to a hit being a 2B or 3B that makes them different from a single.

The only consistent rule with BABIP is that players who hit more line drives have higher BABIPs. So you are right that players who hit the ball hard generally have better BABIPs than those who hit a lot of grounders and fly balls. But that's really the only statistically significant factor that has been found (IIRC). I wish I had a link to a site that had information on line drive rate or a study that demonstrated this result, but I don't remember where I read that stuff.

PostPosted: Sat Apr 29, 2006 2:16 am
by BobbyRoberto
From what I've read, BABIP is much more applicable to pitchers than hitters. The basic idea is that pitcher's don't have much control over what happens once the ball is hit. This is why high strikeout pitchers are more desirable.

On the other hand, hitters do seem to control what happens when the ball is put in play. Hitters' BABIP has a much higher correllation from one season to the next than pitchers' BABIP.

What this means in the example of Michael Young, from a previous post, is that you can expect Young to regress to his established levels, but not all the way down to .300, just because .300 is league average.

But for a pitcher who is giving up a .400 BABIP, you can expect regression toward the .300 level.

PostPosted: Sat Apr 29, 2006 2:27 am
by BobbyRoberto
In addition to my previous post, I want to add that I think looking at a hitter's BABIP can show you players who can be expected to improve, or regress.

Looking at a guy who is really struggling in the early going: Jeff Kent.

Jeff Kent is hitting .197/.333/.268, .601 OPS.
In '04 he hit .289/.348/.531, .880 OPS.
In '05 he hit .289/.377/.512, .889 OPS.

His BABIPs for those years:
2004--.309
2005--.298
2006--.228

His Line Drive %:
2004--20%
2005--21%
2006--22%

His GB%:
2004--39.3%
2005--33.7%
2006--38.6%

I would guess that Kent's extremely low BABIP in 2006 is an outlier, especially considering he is hitting line drives at a higher rate than in '04 and '05 and his GB% is right in line with the other two years. He should improve.

On the other hand, you have the Amazing Kevin Mench.

2004--.279/.335/.539, .874 OPS
2005--.266/.331/.472, .803 OPS
2006--.343/.362/.687, 1.049 OPS

2004--.275 BABIP
2005--.265 BABIP
2006--.333 BABIP

Not that this is surprising news for anyone, but Mench is headed for a fall. The fact that he has yet to walk in 69 plate appearances is also a big warning sign.

PostPosted: Sat Apr 29, 2006 2:50 am
by mbuser
good stuff guys -- even taking your views of stats this one step further than the 'standard' numbers, you give yourself that much of an advantage over a good number of fantasy managers. this is definitely a good stat to track, particularly when looking at hot/cold starts

also it seems to me that a pitchers BABIP would be affected a decent amount by his defense and with luck playing a miniscule part, while a batters BABIP would be in large part due to the hitter himself with some luck thrown in