Using Retrosheet, I created a database table that showed for every combination of catcher and pitcher, how many plate appearances there were with runners on base, and how many times was there a wild pitch or a passed ball. Then repeat by catchers only, and by pitchers only.

So for Uecker, I know how many PAs with runners on base, how many WP and how many PB when he was catching Niekro, and when he was catching any other pitcher. If I take Niekro’s pitcher’s totals, and subtract off what he and Uecker did together, then I know how Niekro did with every other catcher. Therefor, I can compare Uecker catching Niekro to everyone else who caught Niekro. Repeat for each catcher and each pitcher, and sum the results.

I don’t know how the catcher avoided more wild pitches, but I can measure how many.

Dave Allen recently wrote an article at Baseball Analysts http://baseballanalysts.com/archives/2009/11/a_pitchfx_look.php that examined catcher’s ability to block pitches based on the location of the pitch.

]]>Where do you get the data on how many pitches Freehan caught from each pitcher with a batter on base? It seems to me there are a lot of assumptions here about things evening out that are not only unproven, but unlikely.

Is it just a coincidence the Uecker caught knuckleballer Phil Niekro in 1967? In fact, wasn’t Atlanta looking for a guy who could catch a knuckleballer when the traded for him?

“that seems unlikely that a dozen or more players would have a random variation biased towards one direction,”

I don’t see why that is unlikely. In fact, it seems to me in the sample of all major league catchers you would expect to find several examples of where that happened.

But there is another question here. HOW did the catcher avoid passed balls and wild pitches. Was it because pitchers didn’t throw in the dirt or because the catcher didn’t call for a knuckleball.

]]>On the other hand, by using career you run a risk of overvaluing a guy like Ramon Hernandez, if his staff does better than their career numbers – but that seems unlikely that a dozen or more players would have a random variation biased towards one direction, other than just about the mean. I think that’s vindicated by Hernandez’s 2007 & 2008 ratings, despite a high expected value, fell right in line with his previous years and career totals.

]]>Last year there were 46 WP and 10 PB with Hernandez catching. That number of WP was 2nd highest in 2008 behind Bengie Molina’s 54, but my formula expected him to allow 63 WP and 11 PB, the 63 expected WP the highest in MLB in 2008. Of the Orioles top 7 in IP in 2008, only Garret Olson was avg at .016, then Burres .018, Guthrie .020, Cormier .021, Cabrera .031, Liz .033, Sarfate .033

]]>But also, with the list of active players, to get an idea of what the range of ability there is on defense for catchers, and to think that Gary Carter once had a +28 season.

]]>– Jeff

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