Once again, I failed to keep up with monthly updates to my catcher defense rankings, although I did get a couple of installments done during the season. The Gold Glove awards are coming out later tonight, so let's see if they get it "right." (ahem)
I often go through a number of qualifications at this point, but you can read past installments for that stuff. I wondered if I should even bother keep doing this, given the great stuff that has come out lately on stuff that is covered here like Bojan Koprivica's work on pitch blocking and other stuff like Mike Fast's revolutionary work on pitch framing. BtBS' own Michael Schatz has some cool stuff coming out, too. Along with WOWY approaches (discussed in the methodological stuff at the end), this is the future of catcher defense evaluation. However, there are virtues to a more simple approach. I originally began doing this for my own sake, to have something that can easily be copied, pasted, and "manipulated" for my own tastes the Baseball-Reference basic fielding tables. My own quick perusal seems to show basics agreement with more complex approaches, which, along with the Fans Scouting Report, I encourage you to check out. I will not pursue those comparisons here. I may use a different approach in future seasons, or just leave this stuff to others. For now, I'll just make some comments on a few of the leaders and trailers. Brief methodological comments and summaries can be found after the table.
One more thing: please remember to keep the distinction between "observed performance" and "true talent" in mind before getting to worked up about a particular rating.
The overall leader is the same guy who has been running away with it all season, Matt Wieters, who dominated these leader boards like he was supposed to dominate major-league pitching immediately upon his promotion in 2009. He is not just the overall leader, but also the best at blocking pitches and catching base stealers according to these rankings. His offense may not ever reach expectations, but by itself it was good enough relative to his position without good defense. With his defense, he probably had a better than five-win season. Maybe it is not the way Orioles fans envisioned, but Wieters has become a star, even if it is mostly going unnoticed.
There are some other notable players near the top of the ratings. Some of the usual suspects come in as above average, like Yadier Molina (#8) and Carlos Ruiz (#5). However, the players who rank immediately below Wieters are a bit surprising. Miguel Montero (#2) is not a catcher with much of a defensive reputation, but his good fielding and strong bat adds up to an underrated piece of the Diamondbacks' surprising run to the playoffs. Lou Marson has an absolutely dreadful bat, but his glove makes him quite playable, especially has a backup. Kelly Shoppach (#4) used to be known as an offense-first, right-handed platoon catcher, but in a season when hit bat fell apart, he thrived on defense. Speaking of catchers with a reputation for bad defensive and platoon offense, how about thatMike Napoli (#12)? I will be generous and not name the person who told me, at the time of the trade, that Mike Scioscia was "right about Napoli."
Among those at the bottom we have the Mr. Hockey Jersey "C," Jason Varitek (#109) and part of Milwaukee's SuperGlove combo, Jonathan Lucroy (#110). A.J. Pierzynski (#111) might be better served to stick with commentary. Well, better serving his team, not his listeners. Jarrod Saltalamacchia (#112) restored his credibility on offense, but his defensive numbers aren't so hot. However, his =passed ball and wild pitch numbers have to be taken with a grain of salt given that he caught a knuckleballer. Speaking of passed balls and wild pitches, Miguel Olivo (#113) continued his reign of terror. Oh well, at least he gets on-base. Oh, wait. At the very bottom is another guy who was basically at the same rank all year, a Blue Jays rookie J.P. Arencibia. Arencibia hit a lot of home runs this season, but that was about all he did well. If he doesn't develop, he could be another Olivo. That has its uses, but with Travis D'Arnaud hitting in the minors, Arencibia's time to prove himself in Toronto may be running short.
Concluding Methodological Postscript
I should make clear that for the purposes that I am not including such debated areas a pitch framing or the more amorphous "game calling." I am not taking a position one way or the other on either of those, simply making clear the bounds of these rankings. When I discuss "catcher defense," like most others, I will be discussing preventing stolen bases, blocking pitches, etc.
One of the difficulties with evaluating catcher defense with regard to even these issues is that, much more than with other fielding positions, the catcher's performance is dependent on another player -- namely, the pitcher. No matter now strong or weak the catcher's arm is, he can't escape the reality that he depends on the pitcher's skill with regard to holding runners, quickness to the plate, etc. While the catcher's skill with regard to blocking pitches that are off the mark is clearly important, catching Tim Wakefield poses a unique challenge (just ask Josh Bard). And so on.
For these reasons, probably the best way of measuring catcher defense is Tom Tango's WOWY (With or Without You) method of defensive evaluation as detailed the 2008 Hardball Times Annual. You can read about the details in the links provided. Versions of WOWY for catchers have also been done by Brian Cartwright and Dan Turkenkopf. I would do it that way if I could. The main issue is that 1) it's pretty complicated, and beyond my present capabilities, and 2) it requires something like Retrosheet, which isn't available until after the World Series is over, so even if I could do it, I couldn't get the numbers during the season of even now...
While the method used here is neither terribly subtle nor original, I think when compared to things like the Fans' Scouting Report and WOWY methods, it compares fairly well. Just keep in mind the acknowledged limits (e.g., not taking into account the pitchers' contributions like WOWY does).
The Method Used Here
For non-WOWY catcher defense, the basic idea is to 1) choose what events you're going to deal with, 2) determine each catchers performance with respect to league average, and 3) decide the run value of each event.
Stolen Bases/Caught Stealing (CSRuns): First, we figure out the league rate for caught stealing. One cool thing about the new Baseball Reference is that it separates out the catcher caught stealings from the pitcher pickoffs, so we can exclude the pickoffs (not under the catcher's control) from the equation. So we total the CSctch +SB to get total stolen base attempts (SBA) and then to total CSctch/total SBA for the lgCS rate. We use the weight of .63 runs for each caught stealing, which represents the average linear weight of the caught stealing (.44 runs) plus the weight of the stolen base not achieved (.19 runs). The formula for runs above/below average for each catcher is thus (CS - (lgCSrate) * SBA) * 0.63.
Wild pitches/passed balls (WPPBRuns): The league rate is (WPlg + PBlg)/lgPA. The linear weight for each passed ball/wild pitch is 0.28 runs, which we make negative since the more WP/PBs a catcher has, the worse his defense is. The formula for each player is ((WP + PB) - (lgWPPBrate * PA)) * -0.28.
Errors (FcE and TE Runs): I deal with three different kinds of catcher error recorded by Baseball Reference: throwing errors, catching errors, and fielding errors. I've assimilated catching errors to fielding errors. There are separate linear weights for throwing (including catching) errors (-0.48) and fielding errors (-0.75). The method is the same as above. Get the league rate, then see how far over/under the player is. For throwing errors: (TE - (lgTErate * PA)) * -0.48. Fielding errors: (FE - (lgFErate * PA)) * -0.75.
Then you just add them all up to get the total runs above/below average. It's not perfect, and hopefully, there will be some improved options soon, but the results do seem to reflect reality. I round to one decimal: I aware that gives an illusion of precision that isn't there, I simply do it to expedite sorting and ranking. I thought about coming up with a "rate" version like UZR/150, but that isn't as simple as prorating for innings caught/PA -- one needs to normalize each sort of event separately, the chart is confusing enough as it is. For now, this is just a value measurement of what each player did this season.