THE BOOK--Playing The Percentages In Baseball

Thursday, January 31, 2008

WOWY: Measuring the DP

I’m starting to cast my With Or Without You (WOWY) system to the double play.  I thought it would be fairly straightforward: count the 4 base states with a runner on 1B, likely separately, outs less than 2, find out who the other guy’s DP partner was, the handedness of the pitcher/batter, and/or the tendency for the pitcher/batter to get balls hit to 2B or SS, lather, rinse, repeat.  But, Peter brought up many points in an email exchange, of which I will post here, and I hope others can chime in with their thoughts.  Note also that I’m not looking necessarily as to an evaluation as to whether it’s worth it or not.  I’m only looking at the consideratations, the parameters to think about:

That was my first approach too.  But as I thought about it more I concluded that what I was trying to measure was the interaction of the SS and 2B; in other words the two different double play skills, starting a 6-4-3 double play and making the pivot on a 6-4-3 double play SEPARATE from a players fielding ability, which my fielding metric had presumably already measured.  That meant subtracting infield singles to short and fielding errors to short which the fielding metric would have covered.  It also meant subtracting 6-3 double plays (but giving the SS full credit for above average numbers of those in another column) since they didn’t require the skills I was trying to measure.  I also subtracted out all the plays where the runners were running on the pitch. Even though some DPs still occured on those plays, the rate is 25% of that when runners aren’t running.  I suppose plays where the SS goes for a lead runner at third or home should also be removed too.

For the 2b pivot skills the DP opps should probably be only those balls thrown to him;6-4-3 DPs and 6-4 forceouts unless you believe that the SS sometimes doesn’t try for the DP because the 2B is incorrectly out of position for a throw, which I think is doubtful.

I am still struggling with whether there is still a penalty for being an above average fielding SS that gets to balls that where he can get a force at 2B but not a DP, and that a poorer fielding SS would not have gotten to at all.

As I said before, probably not worth the mind effort to get it theoretically correct considering the small actual values involved.  But certainly more complex than it first appears.