Posted Under: Stat of the Week
We have spent a lot of time looking at statistics that are helpful to allow us to properly evaluate hitters and how the game has involved from looking at hitters through just Batting Average, Home Runs and RBI or pitchers through just Wins, Losses and ERA. Today, we’ll look at a statistic that caused some debate on its usefulness and has actually been thrown to the wayside in the sabermetrics community in terms of its effectiveness.
That statistic is Catcher’s ERA (CERA) which looks at the combined ERA of a starting catcher and hopes to explain which catchers are the best at calling games and improving the quality of their pitchers. Remember that ERA has its own limitations as it does not take into account external influences such as park factors, the defense behind a pitcher and in the case of CERA, the pitcher himself can also negatively or positively affect how we view a catcher defensively.
The death knell delivered to CERA has been credited by different sabermetrics bloggers to R.J. Anderson of Beyond the Box Score who investigated why backup catchers such as Paul Bako kept getting hired by teams even though he was an offensive light weight with an OPS of .620. Bako, according to Anderson, was seen as a defensive stalwart and that was why teams continued to hire his services year after year. Unfortunately for teams such as the Brewers, Bako’s effect was overrated as he only improved the pitching staff’s Fielding Independent Pitching by .04.
Anderson concluded his argument by comparing the CERA of Jason Varitek, long considered a great game caller, and Michael Barrett who was known more for getting into fights with his pitchers than his ability behind the plate. Evaluating both catchers through CERA over 10 years, Anderson found that the statistic did not do its job in telling us what our eyes are seeing in terms of Varitek being the superior defensive catcher than Barrett, and thus was not trustworthy when evaluating catchers in general. Next week we will look at statistics that do add value to our understanding of a catcher’s effect on a baseball game looking at Stolen Base Runs Saved, Passed Pitch Runs and the strides made in research on the pitch framing ability of catchers.
Have a safe and Happy Thanksgiving!