Last week, we looked at the unusually wide strike zones that both Mariano Rivera and Brian Wilson have enjoyed in recent years. In that post I suggested that wide strike zones aren't just for top-notch relievers. This week, we look primarily at starters who get the benefit of the doubt.
Let's start with the most fortunate pitcher over the last two years (minimum 500 pitches), Livan Hernandez.
As you can see, Livan makes his living by pounding the outside corner. And he gets it—especially against lefties. Compare Livan's personal zone vs. the typical zone for right-handed pitchers.
Same as with Mo and Wilson, it's not surprising that Livan gets the corner, but it is surprising that he gets so much of it. Why is Livan so successful here? And for that matter, why is Derek Lowe almost as successful?
Derek Lowe has a very similar zone to Livan Hernandez: he gets the outside corner, especially against lefties. Aside from the fact that he keeps his pitches lower, he also gets the inside corner on right-handed batters. In sum, they're both veteran, right-handed starters who have been fortunate with the zone, as you can see below.
|Pitcher||Called Pitches||Balls in Question||Strikes in Question||Zone Advantage||Standard Deviations|
|Herrera, Daniel Ray||769||38||73||4.6%||1.02|
|Spring Training||Home Field||Location|
The table above lists the variables that I have found consistent (and statistically inconsistent) with a favorable call on a specific pitch. Controlling for location, fastballs with strong horizontal or (especially) vertical movement are more likely to favor the pitcher. Contextually, an umpire is most likely to call a strike that the Pitch FX system disagrees with when the pitcher is pitching at home, in the playoffs, facing a left-handed batter, when the there are more outs, more balls, and fewer strikes on the batter, and/or when there are runners on first and/or second, ceteris paribus.
The inning during which the pitch was thrown, the handedness of the pitcher, and the velocity of the pitch were irrelevant when controlling for the aforementioned factors (if you'd like to dig deeper into the findings, and don't mind sifting through raw output from statistical analysis software, feel free to check out the tech notes on my blog here).
When we look back at the pitchers of record with this new information, the results start to make sense. Livan, Moyer and Lowe all throw fastballs with substantial movement, not the least of which is because they don't throw very hard in the first place. As contact pitchers, they also tend to pitch with runners on more than others.
As for our subjects from last week, Mo and Wilson both rely heavily on fastballs with movement.
The reason for the disproportionate RHP representation on the list? Well, first of all, there are more righties than lefties in baseball. But also, RHPs are far more likely to face lefties than LHPs are, and umpires give right-handed batters more leeway.
That, in a nutshell, is what it means to get the benefit of the doubt in the majors. Be sure to tune in after Thanksgiving, as I detail the starters and relievers who weren't as fortunate as their colleagues according to Pitch FX.
As usual, my data originate from Darrell Zimmerman's SQL-based PitchFX database.