H/BIP

[Patrick425]

Ok, I'm not nearly as up on sabermetrics as many on this site are and I hate to open a can of worms. However, there was an article posted on Sportsline.com last week regarding how to determine who might be comeback pitcher candidates this year. I can't link to the article, because I believe it's only for users who subscribe to the Fantasy baseball comissioner product on that site. However, the writer points out Chis Capuano as a prime comeback candidate and sites 3 main stats that point to this. BB/9, K/9, and H/BIP (Hits for Balls in play). The last stat he mentions as being important because "For pitchers, the H/BIP rate is random; research has not found anything that a pitcher can do to influence whether a hit ball is an out once it leaves the hitter's bat. The increase in ERA for this pitcher was nothing but bad luck"

 

I just don't get this. Yes I understand that once the ball is hit, the pitcher can't do anything about it. However, isn't a hanging curve easier to hit than a nasty slider? There is a difference between a lazer beam that careens off the right-center field wall and a slow dribbler to 1st. Usually the pitcher has something to do with that difference. I don't know that I'm ever going to understand the whole BIP methodology.

[Baldkin]

BABIP (batting average for balls in play) for pitchers is usually very close to the same across the board (about .300), with the exception being very strong groundball pitchers, theirs will be a bit lower.

 

Although, one of the guys over at THT agrees with you.

 

Yes, the pitchers effect BABIP, but when most pitchers keep it around the same level for their career, and Capuano had a huge spike in his last year (from about average .295 for his career, to .339 last year), so its probable that he will regress back towards his personal mean.

[TooLiveBrew]

"For pitchers, the H/BIP rate is random; research has not found anything that a pitcher can do to influence whether a hit ball is an out once it leaves the hitter's bat. The increase in ERA for this pitcher was nothing but bad luck"

 

This statement is simply untrue. It's all in the phrasing - as Baldkin mentioned, P do have a limited amount of control over BABIP, and there have been guys that do seem to supress BABIP, but not very many guys. Instead of saying that there's 'nothing a P can do to influence...', one (I know the above was the writer's quote) would be best served by stating, 'research has not found much evidence to show that a pitcher has more than a miniscule amount of control over BABIP.'

 

The rate is not totally random, but it's much more accurate to say that it's 'totally random' than that 'the pitcher has extensive control over BABIP.'

 

 

EDIT: Yes I understand that once the ball is hit, the pitcher can't do anything about it. However, isn't a hanging curve easier to hit than a nasty slider? There is a difference between a lazer beam that careens off the right-center field wall and a slow dribbler to 1st. Usually the pitcher has something to do with that difference.

It's not that a good pitch isn't any more effective than a bad one, it's that BABIP tends to jump around while hovering near .300 for almost every pitcher. P clearly do have some amount of control, but in terms of analyzing the stat, it's not one that correlates to talent very well. It can, however, help explain seasons that otherwise seem abberations from career norms, like Cappy's 2007.

 

Keep in mind that defense and the scorer heavily influence BABIP.

[lukevan]

However, isn't a hanging curve easier to hit than a nasty slider? There is a difference between a lazer beam that careens off the right-center field wall and a slow dribbler to 1st.

 

The difference you're describing here I would guess would be seen in SLG% against, HR% and/or HR/FB% for a pitcher moreso than in BABIP.

[rluzinski]

The way I like to say it is that the spread of the true talent of a pitcher's ability to control H/BIP is very small. In contrast, the spread of H/BIP over 200 innings is very large. As the sample size increases, the sample spread is going to approach the true talent spread.

[Ennder]

Yes the pitcher has some control because flyballs have a lower BABIP and groundballs have a higher BABIP. Also different counts come with different BABIP so pitchers who are always ahead in the count tend to have slightly lower.

 

Generally speaking a pitcher will regress towards his career rates and the range of sustainable BABIP is pretty small.

 

I think the key is if a pitcher maintains all of his rate stats but his BABIP is off his career pace he pretty much just had bad luck. If all of his numbers look strange then BABIP trends aren't as reliable. You don't just give up more hits and not have your BB/9, K/9, ISO etc change, when you are pitching poorly more than just one of those things should change.