BABIP

[homer]

I've recently 'discovered' this stat (thanks Ennder) which is to say I've recently started to care about it. So I took a look at some Brewer BABIPS to see what it might tell us about next season and I think things look pretty good for a few guys. I hope some more familiar with this stat can confirm my interpretation. By the way, what is considered 'average' BABIP? Good? Elite?

 

player/BA/BABIP

 

Fielder/.281/ .284 - I take this to mean that Fielder is not getting lucky at all when he gets a hit and we could look for a nice rise in BA next season.

 

Hardy/.275/.276 - Even less lucky than Fielder. Given that his BABIP the previous two years was about 20 points higher than 2007 I would think his BA would climb next year.

 

Braun/.334/.379 - Getting lucky. His average will probably drop next year but not down to the .270 level or anything.

 

Hart/.280/.315 - I think this is about normal for a major leaguer. Am I wrong about that?

[Phenomenal Smith]

The league average is usually around .300 or so.

[sbrylski]

A thing to note about BABIP is that it can be influenced by the batter, mostly by their LD%. Its not pure luck. Comparing a player's BABIP to their expected BABIP, rather than to league average, can yield more accurate predictions.

 

xBABIP = LD% + .120

 

Player - BA / BABIP / LD% / xBABIP

Fielder - .282 / .284 / .199 / .319 - I agree, his batting average should rise a bit next season. He'll have some seasons over .300 in his career.

Hardy - .278 / .280 / .173 / .293 - Hardy has only been a little more unlucky than Fielder this season, however his LD% this year is lower than ever, so that could rise next year. Interesting to note that his career BABIP is .271, yuck.

Braun - .332 / .374 / .178 / .298 - Yes, very lucky. I don't know if we really expected him to be a career .330's hitter though. Right around .300 with 40 HR is fine with me.

Hart - .285 / .319 / .182 / .302 - He's pretty close to normal, yes. His batting average is also about what was expected from him. BABIP can usually explain away slight under or overachievements.

 

You can see how xBABIP for the entire league would rest around .300, or slightly above.

 

Also, I get my LD% from Fangraphs.com.

[homer]

Interesting stuff, Sbrylski. Thanks for the info. Fangraphs is cool!

[Phenomenal Smith]

If I remember correctly, and perhaps I don't, the LD% +.120 formula seems to work a little better in the AL. The NL seems more like around LD% +.110. Granted that's not too much of a difference, and maybe it's explained by pitchers hitting in the NL.

[Baldkin]

Pretty nice article over on THT about babip and hitting balls in the strike zone.

 

http://www.hardballtimes.com/main/article/squaring-it-up/

[logan82]

How useful is it to use BABIP compared to batting average to look at a player's plate dicipline? It seems to me that having a high BABIP compared to your average would indicate that you strike out a lot.

[TooLiveBrew]

I think that's right, logan. I remember being constantly inundated with Jose Hernandez's BABIP during his horrendous K year. The announcers were (seemingly) always saying, 'Well, you know, when he hits the ball in play, his BA is ___!'

[logan82]

As I was looking for the Braun is going to regress discussion I noticed that players like Fielder, Carlos Lee, and Pujols had a BABIP either lower or very close to their BA. Players that are considered to have a good approach at the plate.

[TooLiveBrew]

Yet another reason "luck" is used quite a bit to describe high or low BABIPs, huh?

[logan82]

BABIP looks like it would be closer to your BA the less you strike out. Also, if you are good at sacrafice flies that would lower your BABIP.

[rluzinski]

The way I see it, you should compare BABIP compared to the league average as a starting point. As pointed out, comparing it to the player's BA is telling you mostly about the guy's strikeout rate.

 

As a rule of thumb, when you find anything in life that's much higher or lower than expected, the "luck factor" should probably be the first consideration.

[TooLiveBrew]

What about Fielder's 2007 BABIP? It's nearly identical to his BA, and though he doesn't K enough to lead the league, he certainly strikes out his share.

[logan82]

It does seem pretty apparent that a player can carry a higher or lower BABIP year to year, but the players who carry a higher one I would guess are guys who K alot.

 

I found Carlos Lee's BABIP over the last 4 years interesting. .310/.259/.281/.290

[rluzinski]

It does seem pretty apparent that a player can carry a higher or lower BABIP year to year, but the players who carry a higher one I would guess are guys who K alot.

 

Higher or lower, compared to his BA?

[logan82]

Higher than his BA. I will probably look into it at some point just out of interest, but I would guess if you look at the league K leaders my you would see many BABIPs far over .300.

 

EDIT: Quick look shows that most players at the top of the K list carry around a .300 BABIP and a pretty poor average.