Now that instant replay has been expanded in MLB to include about 90% of all on-field plays, it seems logical that the next area up for consideration to use reviewable technology would be the strike zone.

While I have been a staunch proponent of getting all calls right in baseball, the idea that we could soon be reviewing balls and strikes, or replacing umps with an electronic strike zone seems so… sacrilegious.

Traditionally, the home plate umpire has presided over home plate like a judge who presides over his court.  He may not get every call right, but that’s just how things go.  That’s how it’s always been done in the history of the 100 year-old sport.

But, I do wonder – just how many calls are the umps behind the plate getting wrong?  Is it enough to start tinkering with the home plate tradition?

According to an essay by Brayden King and Jerry Kim dated March 28, 2014 for the NY Times, home plate umpires called pitches erroneously about 14% of the time during the 2008 and 2009 seasons.

This conclusion was made as a result of research published in the journal Management Science based on 700,000 non-swinging pitch calls analyzed during that time frame.

Even more disturbing than the 14% error rate, is the other data that King & Kim uncovered in this same research.

Namely, that umpires showed bias in how calls were made:

  • Umpires tended to favor home teams by expanding the strike zone (“calling a strike when the pitch was actually a ball 13.3% of the time for home team pitchers vs. 12.7% of the time for visitors”);
  • Umpires were influenced by pitch count:
    • They did not seem to like calling strikes on a 0-2 count; and
    • They really didn’t like calling a ball on a 3-0 count;
  • Umpires missed more calls when the game was on the line (“13% more likely to miss an actual strike in the bottom of the 9th inning of a tie game than in the top of the 1st inning, on the first pitch”);
  • Umpires showed favoritism towards All-Star pitchers by expanding their strike zones;
    • Also, if the All-Star pitcher had a reputation for “precise control”, they were viewed differently than those less precise counterparts.
    • By contrast, umpires tended to shrink strike zones for non-All Stars; and
  • Racism was present in the umpires’ decisions.  While it wasn’t the biggest factor, umpires were 10% less likely to expand the strike zone for African-American pitchers.  But, race was not influential whether an ump called a pitch a ball when it was actually a strike.

To me, this is all very much surprising.  As I outlined above, I only first thought about protecting the human aspect of the strike zone due to tradition.  I never thought much about the bias a human being brings to the most basic of all the baseball principles, beyond getting calls right.

But, now that this data has been brought forth, tradition has no place in the discussion.

Since bias has been uncovered, the sport should consider this an urgent matter and not continue to let it filter into baseball in this way.

Whether or not the umps realized they were letting their personal opinions of the situation or players filter into the game, King & Kim’s research brings to light that human error is inevitable (based on missed calls and/or bias) and should not continue.

And, the best way for baseball to avoid all of this and bring fairness back into the game – is to introduce an electronic strike zone (assuming the data collected was based purely on information collected by high-speed video footage) –  immediately, tradition or not.


Source : What Umpires Get Wrong

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