Kenny Lofton - BABIP. A question.

[swordsman]

Ok, I have a question. If this has been answered before, forgive me, but what is the explanation for why a player's BABIP would steadily decline? If BABIP is a measurement of the balls hit into play that don't result in an out, what would cause that to decline?

Is it a function of age? (i.e. bat speed, running speed, etc.) Are most if not all players victims of it as they age? If not, why not?

What player actions effect BABIP? Do players purposely hit the ball to where the fielders aren't or is it generally random? If it is random, what would cause a steady decline? Other teams defending the player better? The law of averages?

If players do hit the ball intentionally where the fielders aren't, wouldn't a decline be reversable?

[Transmogrified Tiger]

Ok, I have a question. If this has been answered before, forgive me, but what is the explanation for why a player's BABIP would steadily decline? If BABIP is a measurement of the balls hit into play that don't result in an out, what would cause that to decline?

Is it a function of age? (i.e. bat speed, running speed, etc.) Are most if not all players victims of it as they age? If not, why not?

What player actions effect BABIP? Do players purposely hit the ball to where the fielders aren't or is it generally random? If it is random, what would cause a steady decline? Other teams defending the player better? The law of averages?

If players do hit the ball intentionally where the fielders aren't, wouldn't a decline be reversable?

 

Basically, I'm pretty sure it's an age thing, BABIP is like AVG in that it deteriorates with age for the same reasons. Someone else can likely explain better than I.

 

Relating to Lofton, he was in a decline before this year, and had been around a .300 BABIP for about 6 years. This year, .365. As you can see, it's well out of line for what he's been doing since his Cleveland days. That's why some(myself included) are predicting a precipitous decline for Mr. Kenny.

[Diffusion]

The vast majority of BABIP decline is, I suspect, is a combination of 1) loss of speed to first base, meaning less cheap infield hits, 2) more flyballs as hitting on the ground becomes less effective (flyballs that stay in the park are turned into outs more often than groundballs, and those that leave the park don't factor into BABIP), 3) poorer eyesight and 4) slower reactions, meaning slower pitch recognition and less precise bat control, and so less very well hit balls.

 

It's not quite fair to say that whether a ball in play goes for a hit is random, but pretty much. Certainly hitters don't have a huge amount of control over it, not in the long-term. At-bat per at-bat, sure, the majority of hitters can take a fastball down broadway on 2-0 and deposit it for a hit, but the trouble is that not every at-bat features such a generous pitch, and over the course of the season any hitter will see an extremely unpredictable distribution of pitches.

 

Regarding Lofton, here's the decline in his BABIP (using 5 year stretches to try and drown out small sample size statistical background noise)...

 

1991-95: .343 BABIP

1992-96: .345 BABIP

1993-97: .361 BABIP

1994-98: .346 BABIP

1995-99: .342 BABIP

1996-00: .334 BABIP

1997-01: .320 BABIP

1998-02: .301 BABIP

1999-03: .301 BABIP

2000-04: .291 BABIP

2001-05: .302 BABIP