From Scott Lindholm at Beyond the Box Score on January 27, 2014, with mention of SABR member Daren Willman:
I wrote a post last week on how often pitchers gets calls on pitches outside the strike zone. It had far too many moving parts, but the idea still intrigued me. I realized there was a simpler way to convey this information, which was to investigate two questions:
1. How often was a pitch inside the strike zone called a ball?
2. How often was a pitch outside the strike zone called a strike?
Just to be clear, 13.2% of pitches inside the strike zone were called balls and 86.8% were correctly called strikes. Likewise, similar numbers of pitches were called correctly and incorrectly. It’s beyond my ability to determine how close any of these pitches were to the strike zone, but common sense and watching games on TV suggests the “bad” calls were on pitches right on the edge of the strike zone.
Read the full article here: http://www.beyondtheboxscore.com/2014/1/27/5341676/how-well-do-umpires-call-balls-and-strikes
Originally published: January 27, 2014. Last Updated: January 27, 2014.