dillpickle wrote:I have never understood the validity of the BAPIP stat. Just seems to me that comparing this to league averages and other individual players is pointless. Considering the fact that you take strikeouts out of the equation, the comparison of BAPIP between a player who strikes out a lot to a player who doesn't strike out much is a waste of time.
It is like comparing a guy who goes 5 for his first 10 AB's to a guy who goes 40 for his first 100 AB's. A guy who strikes out a lot by the nature of the stat is going to have many few AB's (as used in the calculation) then a guy who doesn't strike out much. As for me, even though a guy goes 5 for 10 and has a .500 average overall, I'd still put a lot more value in the guy who can go 40-100 even though his overall average is lower. The comparison is apples to oranges.
So Ichiro who doesn't strike out at all, has many more at bats as used in the calculation. So his .360 BAPIP is very good. Then you take a guy who strikes out 150 times a year, his at bats are lower and each hit is magnified in the percentage. How can a valid comparison be made?
It's about regression to the mean, and consistency. That's where the BABIP figure is applicable. If a player has posted a BABIP of .280 for 5 years, and suddenly he's got a .400 BABIP for the first month of a season, chances are it's unsustainable, because he's pretty much shown what he is, and barring minor fluctuations based on new tendencies, progression, etc. the player is who he is. In the case of Austin Jackson, .530 is simply unsustainable no matter who you are, which is really falsely inflating his average. Sooner or later these balls that are finding green grass are going to start being caught, and the regression to the mean (whatever his mean is, since we don't know yet).