Comments on: Stealing on Catchers (Not Named Molina)

By: MGL

MGL — Tue, 17 Feb 2009 02:20:57 +0000

Brian, great work! Have you done the same thing for pitchers?

By: mko

mko — Wed, 28 Jan 2009 14:10:45 +0000

At the Metrodome and Rogers Centre there is no dirt on the basepaths, only at the bases…

By: Nathan

Nathan — Wed, 28 Jan 2009 01:50:40 +0000

Why would the type of turf matter? The baserunner would be running on dirt and the catcher would be throwing from dirt no matter the type of grass.

By: Sam

Sam — Wed, 28 Jan 2009 01:32:16 +0000

Add to win values?

By: Brian Cartwright

Brian Cartwright — Tue, 27 Jan 2009 22:49:36 +0000

Thanks. My goal in writing these pbp tools is to get them to agree well with what others have done for major leaguers, so that I can then apply them to minor leaguers with a known degree of confidence.

By: Xeifrank

Xeifrank — Tue, 27 Jan 2009 19:22:28 +0000

Looks like you have some fairly decent agreement with Tango’s Fan Scouting reports for 2008. The fans like Y.Molina the best, followed by J.Mauer, J.Molina and I.Rodriguez. B.Molina probably drops down to the bottom half of the top 10. The fans don’t think much of R.Martin’s accuracy, and wouldn’t make the fans top 10 at all. Nice work!
vr, Xeifrank

By: Brian Cartwright

Brian Cartwright — Tue, 27 Jan 2009 17:54:43 +0000

I believe this is something scouts do, as they are looking at amateur players, and want an objective measure of ability.

But, with the pros, what we have is pbp, and so I’m working on tools to derive the most I can from that pbp.

By: Peter Jensen

Peter Jensen — Tue, 27 Jan 2009 17:28:21 +0000

Brian – Log 5 works less well the farther percentages get from .5. Thats why it is OK to use for team winning % where the mean is .5 and the range is relatively small, but really shouldn’t be used for other analysis.

By: Xeifrank

Xeifrank — Tue, 27 Jan 2009 17:18:02 +0000

I wonder how these (and others?) results would line up vs taking a stop watch and determining on average how long it took for a the ball to go from the catchers glove to the fielders glove and 2nd/3rd base. Controlling for pitch outs and perhaps really bad pitches and the like. You could even throw in a measurement for accuracy of throw. There seems like too many factors that are out of the catchers control and that are not consistent that could make a pbp study difficult to do.
vr, Xeifrank

By: Brian Cartwright

Brian Cartwright — Tue, 27 Jan 2009 17:14:13 +0000

Inverse James Function

Sorry, it should be log5 instead of odds ratio, but they are very similar
http://www.diamond-mind.com/articles/playoff2002.htm

After Bill James published it originally in the Abstract, which tells you what pct a given combination should produce. I solved for one of the other variables in the equation.

N = (O*M*(1-E))/(O*M+(E*(1-O-M))) (all being binomials)