THE BOOK--Playing The Percentages In Baseball

Friday, February 13, 2009

R=.50 at BIP = 1500 for BABIP

That number sounds about right.

PizzaCutter gives these results:
r=.174, BIP=250 ... my equation says: .143
r=.253, BIP=500 ... my equation says: .250
r=.696, BIP=3750 ... my equation says: .714
r=.742, BIP=4000 ... my equation says: .727

I’m happy saying that Pizza’s correlation equation would give us
r=BIP/(BIP+1500)

Good job on Pizza to present the data as he did.  Makes my life easier.  I hope this post makes it seem useful as to why to present it in terms of r=.50.  When BIP=1500, r=.50.  So, all you have to do is say when r=.50.  You then have an automatic regression equation.  I can feel Pizza inching closer to my dark side.  Come closer, Pizza.  You are almost there.