Evaluating Livan Hernandez: Is Tricking The Umpire A Skill?

In 2010, at the age of 35, Livan Hernandez had the third best ERA of his career, good for sixteenth in the NL. He was also the most valuable Nationals pitcher.

His success continued in 2011, albeit diminished. His ERA was 4.47. Compared to 2008 and 2009, when his ERA was 6.05 and 5.44 respectively, 4.47 seems quite excellent.

The sabermetric take

It didn’t take long for sabermetricians to call shenanigans. Livan’s xFIP was 5th worst in the NL in 2010 and 7th worst in 2011.

Sabermetricians took this to be evidence of Livan’s poor quality in spite of his ERA. There is a strong, though steadily weakening, consensus that pitchers can only control three things: their walks, strikeouts, and home runs. The number of hits a pitcher gives up is believed to be beyond his control.

FIP was created in accordance with this idea, as walks, strikeouts, home runs, and innings pitched are the only factors in its calculation. xFIP weakens the idea that a pitcher can control his home runs, replacing  the HR term with fly balls multiplied by the league average at which fly balls go for homers.

Livan Hernandez’s FIP was fairly good in 2010 and 2011, though his xFIP was not. Livan Hernandez gave up very few home runs in 2010 and 2011, suppressing both his FIP and ERA. xFIP captures this and adjusts. It gives us a better idea of how valuable Livan’s pitching was.

Another shortcoming

But there is another factor which suppressed Livan’s ERA, FIP, and even his xFIP. In 2010 Livan had 225 more strikes called than he actually threw. Put another way, 11.2% of the strikes Livan threw were not actually strikes. 11.2%!

225 balls is enough for 56 walks and 225 extra strikes surely put hitters into worse counts than they otherwise would have seen. The first factor suppresses ERA, FIP, and xFIP while the second futher suppresses ERA.

If even half of those 56 potential walks had happened Livan’s numbers would have been significantly worse. His BB/9 would have gone from 2.72 to 4.22 (second worst), his K/BB from 1.78 to 1.15 (worst), and his FIP and xFIP both up about by a about a half point (seventh worst and worst).

That is, a stat taking this into account would have Livan ranked as the worst pitcher in 2010, and likely his ERA would have hinted the same.

Is tricking the umpire a skill?

Assigning half of 56 walks to Livan was an arbitrary decision. It would maybe be better to look at the various counts he faced and distribute those uncalled balls amongst them, removing the unduly called strikes. This would lead to a more “reasonable” figure than 56 divided by two.

But there is no denying that 225 uncalled balls is a huge number. In fact, from 2002 to 2011 no pitcher had a higher percentage of strikes called that were not actually strikes than Livan. His luck continued in 2011, when 9.7% of his strikes were actually balls, the second highest mark from 2002 to 2011.


There is no reason to believe this is a skill. The percentage of “unjust strikes” by pitcher varies from year to year. Derek Lowe has some years had amongst the highest such strikes in the league and a few years later had the lowest. Livan has never enjoyed such a high number of unjust strikes.

What do pitchers do?

Every pitch can wind up only one of six ways:

  1. In the strike zone, swung at and missed
  1. In the strike zone, swung at and struck
  1. In the strike zone, taken for a strike
  1. Out of the strike zone, swung at and missed
  1. Out of the strike zone, swung at and struck
  1. Out of the strike zone, taken for a ball

Pitched balls can be “decomposed” into each of these outcomes using data from FanGraphs (see “pitching_analysis_better.xslx”) and these can be used to tell how well a pitcher is doing at fooling batters, at finding the zone, and getting hitters to chase.

This is pitching. Putting the ball where you want it, how you want it, and, knowing the hitter, controlling the damage done. In 2010 and 2011 Livan Hernandez did not do any of these things well. He’s lucky the umpires helped him out. Will they be there next year?