• Are We Ever Biased Towards Umpire Bias?

    There is no question that umpires have biases. The question is whether we want them or not.


    A couple of years ago I reported on a book that I was reading titled Scorecasting by Tobias J Moskowitz and L. Jon Weerthem. This writeup is going to copy a lot of that story. The book is similar to the book Freakonomics, except that it focuses exclusively on sports. If you have an iPad or iPhone, you can download the first chapter for free Ė and just that much changed forever how I watch baseball.


    The chapter is about a bias that umpires have because they are, with the possible exception of Joe West, human. And humans are far more willing to forgive an error of omission over an error of commission. That is, we are more willing to forgive an error caused by doing nothing over an error caused by doing something. And thus humans are for more willing to commit an error of omission over an error of commission, because it gets us into less trouble. Iíll give an example from the book:


    ďIn a well-known psychological experiment, the subjects were posed the following question: Imagine there have been several epidemics of a certain kind of flu that everyone contracts and that can be fatal to children under three years of age. About 10 out of every 10,000 children with this flu will die from it. A vaccine for the flu, which eliminates the change of getting it, causes death in 5 or every 10,000 children. Would you vaccinate your child?Ē


    Most parents opted to NOT to vaccinate their child, despite it halving the chances of their child dying. The thought of doing something to the child which would cause his or her death was worse than the though of doing nothing and doubling the chances of death. The same bias is statistically apparent in umpires when it comes to calling balls and strikes and now I canít help but notice it.


    In 2007, mlb.com installed the pitch f/x equipment in all the ballparks, providing data on 2 million pitches, including 1.15 million called pitches. Suddenly we could see from data how accurate umpires were in calling balls and strikes, and whether there are any circumstances that made them less accurate. It turns out there are.


    A ball that is in the strike zone is called accurately by an umpire 80.2% of the time. But that number dives if there are two strikes on the batter (and it isnít a full count). Then, a ball in the strike zone is called a strike just 61.3% of the time. Heís almost twice as likely to mistakenly count a strike as a ball. Again, donít forget Ė we KNOW that these are really strikes from the f/x data.


    The same thing happens the other way on pitches outside the strike zone on three-ball counts, though itís not quite so drastic. A pitch outside the strike zone is called a ball 87.8% of the time, but if there are three balls (and itís not a full count) itís only called a ball 84% of the time.


    The reason? Because calling strike three or ball four ends the at-bat. Itís active Ė it affects the game far more than giving the batter and pitcher another pitch to resolve the at-bat themselves. The incentive is toward the error of omission rather than that of commission.


    Incidentally, this is most apparent on borderline pitches. Over all counts, a borderline is called a strike 49.9% of the time Ė almost literally a coin flip. But with a 2-strike count (again not a full count) itís called a strike just 38.2% of the time. And with a three ball count, itís called a strike 60% of the time. The percentages become even more extreme on 3-0 and 0-2 counts.


    This may be a bias that we, as fans, want to reward. For the first time, I thought about whether or not I really want to take that kind of call out of an umpireís hands. Donít we want someone who prompts the batter and pitcher to resolve their conflicts themselves? Even if it might not be a perfectly accurate call.

    This article was originally published in blog: Are We Ever Biased Towards Umpire Bias? started by John Bonnes
    Comments 29 Comments
    1. @_2244's Avatar
      @_2244 -
      Ahhh, sports officiating. One of my favorite topics to banter about. Piling on the umpire is one of the easiest things in the world to do. In my opinion, blaming an umpire for costing you a game is the world's biggest "Loser's Lament." I'd be willing to bet the vast majority of the loudest umpire critics are those who have never been behind the plate.
    1. @_2244's Avatar
      @_2244 -
      I would submit that the vast majority of umpire critics have never been behind the plate in a competetive game.
    1. BeefMaster's Avatar
      BeefMaster -
      Quote Originally Posted by John Bonnes View Post
      Here's another question: should the zone be different for right-handed & left-handed batters? Must it be symmetrical?
      If the strike zone varied side-to-side, that implies that home plate no longer defines the zone... that seems like a pretty huge change.
    1. Thrylos's Avatar
      Thrylos -
      Quote Originally Posted by John Bonnes View Post
      Here's another question: should the zone be different for right-handed & left-handed batters? Must it be symmetrical?
      There is a definition of the zone in the MLB rulebook
      It does not say that the zone should be different for lefties or righties. my answer is no
    1. one_eyed_jack's Avatar
      one_eyed_jack -
      Quote Originally Posted by @_2244 View Post
      I would submit that the vast majority of umpire critics have never been behind the plate in a competetive game.
      ---True, but so what? That's true of pretty much everything, isn't it? The vast majority people who criticize politicians have never served in office - does that mean they don't have a right to speak their disagreement? Can you not say the food at a restaurant stinks if you've never been a chef?
    1. powrwrap's Avatar
      powrwrap -
      Quote Originally Posted by one_eyed_jack View Post
      ---True, but so what? That's true of pretty much everything, isn't it? The vast majority people who criticize politicians have never served in office - does that mean they don't have a right to speak their disagreement? Can you not say the food at a restaurant stinks if you've never been a chef?
      Your comparisons aren't quite valid. Umpires make judgment calls that spectators can witness, oftentimes with the assistance of instant replay. Fans are informed and know the rules of baseball but they've never been in the pressure situation of having to make a split second decision based on something they've seen in real time.

      If you were to eat at a restaurant then read a food critic's review of the same food prepared by the same chef your comparison would be legit. Or if you read the same position papers and listened to the same speeches from colleagues that a politician does and still criticize their votes in Congress you might have a comparison.
    1. one_eyed_jack's Avatar
      one_eyed_jack -
      Quote Originally Posted by powrwrap View Post
      Your comparisons aren't quite valid. Umpires make judgment calls that spectators can witness, oftentimes with the assistance of instant replay. Fans are informed and know the rules of baseball but they've never been in the pressure situation of having to make a split second decision based on something they've seen in real time.

      If you were to eat at a restaurant then read a food critic's review of the same food prepared by the same chef your comparison would be legit. Or if you read the same position papers and listened to the same speeches from colleagues that a politician does and still criticize their votes in Congress you might have a comparison.

      ---Even if you accept those distinctions as meaningful, I still don't see how it supports the ultimate conclusion that only people who have umpired themselves are entitled to have an opinion about umpiring.


      But I do think it's cute that you believe that politicians actually read position papers and listen to speeches from their colleagues before deciding how to vote on something.
    1. powrwrap's Avatar
      powrwrap -
      Quote Originally Posted by one_eyed_jack View Post
      But I do think it's cute that you believe that politicians actually read position papers and listen to speeches from their colleagues before deciding how to vote on something.
      Real men don't use the word 'cute'.
    1. powrwrap's Avatar
      powrwrap -
      Quote Originally Posted by one_eyed_jack View Post
      ---Even if you accept those distinctions as meaningful, I still don't see how it supports the ultimate conclusion that only people who have umpired themselves are entitled to have an opinion about umpiring.
      Sure they can have an opinion. Would be nice if it was an informed opinion...
©2014 TwinsCentric, LLC. All Rights Reserved.
Interested in advertising with Twins Daily? Click here.