The post The Automated K Zone & Technology. Is it time? generated a discussion of how good/bad are the umpires at calling balls and strikes. So lets take a look at that question using the Game Day data which is presumably the same data used by the BrooksBaseball.net PITCHf/x Tool.
| Pitch Result | Count |
|---|---|
| Automatic Ball | 5 |
| Ball | 232,520 |
| Ball In Dirt | 15,501 |
| Called Strike | 118,755 |
| Foul | 119,351 |
| Foul (Runner Going) | 2,307 |
| Foul Bunt | 2,413 |
| Foul Pitchout | 1 |
| Foul Tip | 5,970 |
| Hit By Pitch | 1,602 |
| In play, no out | 30,183 |
| In play, out(s) | 84,847 |
| In play, run(s) | 15,500 |
| Intent Ball | 3,348 |
| Missed Bunt | 516 |
| Pitchout | 238 |
| Swinging Pitchout | 2 |
| Swinging Strike | 63,684 |
| Swinging Strike (Blocked) | 5,834 |
The table at right contains the counts for how each pitch in 2015 was categorized in the Game Day data.
In order to use this data we will have to make some assumptions and will also have to exclude some rows. Lets start with considering some measures of agreement:
- How often does the umpire agree with the PitchFx classification for a pitch that is called a strike. The Called Strike row (118,755 pitches) represents pitches that were called strikes by the umpire.
- How often does the umpire agree with the PitchFx classification for a pitch that is called a ball. The Ball row (235,520) are pitches that the Home Plate umpire called balls. Note that the Ball In Dirt pitches were excluded as those are likely not of interest (easy to call??).
- For purposes of comparision, the following pitch classifications were also excluded as no umpire judgment on a pitch being a ball or a strike is required: Automatic Ball, Foul Pitchout, Hit By Pitch, Intentional Ball, Pitchout, Swinging Pitchout.
The pitch data includes a field called Zone. Zone values of 1 thru 9 represent strikes. The Zone values are from the perspective of the umpire. So Zones 1, 2 and 3 are the top of the strike zone and Zones 7, 8 and 9 are the bottom. Zone 5 is probably where a pitcher never wants to throw a pitch to anyone. Any other Zone values are, according to the Game Data Pitch data, balls.
Using this info we can create a few metrics:
- What percent of Called Strikes by the umpire are not in Zones 1 thru 9.
- What percent of Balls called by the umpire are in Zones 1 thru 9.
- Given the exclusions listed above, all the other pitches are ones the batter swung at. So lets combine all the rows where the description is Missed Bunt or begins with Foul, In Play, or Swinging (except for the Pitchout one as that was previously excluded) as those that were swung at by the batter and calculate what percent of those pitchers were actually balls. The idea here is that for umpires that have big (or unpredictable) strike zones, batters are forced to swing at anything close. So this might be an indicator of umpires influence on batters. Clearly it also includes players who swing at bad balls (some on purpose), but lets assume that no umpires have disproportionately more games with lots of bad ball swingers.
The table below show for the 87 umpires who had at least 2500 pitches during 2015 (this cutoff removed just 5 umpires) how they rated on each scale. For example, lets consider the first umpire listed Adam Hamari.
- Only 24 umpires were better at not mistakenly calling a strike on a pitch that pitch fx thought was a ball.
- Only 6 umpires were better at not calling a strike on a pitch that was a ball.
- He was middle of the road in terms of batters being induced to swing at balls.
And to clarify and highlight Batter Swung At A Ball, consider Will Little (last row in the table).
- He is among the best in calling balls as strikes. He ranks highly in terms of not calling a pitch that is a ball as a strike, and not calling a pitch that is a ball as a strike.
- Yet he has a very high percentage of pitches that are balls that batters swing at.
- Perhaps he has his own (minor) variation of the strike zone which teams/batters are very familiar with and that he is consistent with his calls.
Looking at the table, I want to clone Lance Barkdale so he can be the Home Plate Umpire for every game. And if I am a batter, I cringe if Jerry Layne is the Home plate Umpire.
| Umpire | Balls Called As Strikes | Rank | Strikes Called As Balls | Rank | Batter Swung At A Ball | Rank |
|---|---|---|---|---|---|---|
| Adam Hamari | 31.88% | 25 | 2.16% | 7 | 42.90% | 42 |
| Adrian Johnson | 35.31% | 73 | 3.68% | 63 | 42.92% | 43 |
| Alan Porter | 32.65% | 37 | 2.98% | 31 | 41.65% | 11 |
| Alfonso Marquez | 29.45% | 5 | 4.28% | 78 | 42.13% | 19 |
| Andy Fletcher | 33.99% | 60 | 4.32% | 79 | 41.70% | 14 |
| Angel Hernandez | 38.31% | 85 | 2.20% | 9 | 43.79% | 67 |
| Ben May | 30.67% | 17 | 2.38% | 12 | 44.22% | 81 |
| Bill Miller | 36.99% | 83 | 2.09% | 5 | 43.31% | 57 |
| Bill Welke | 32.89% | 43 | 3.51% | 54 | 43.90% | 70 |
| Bob Davidson | 36.32% | 82 | 3.40% | 51 | 43.78% | 66 |
| Brian Gorman | 35.59% | 75 | 3.29% | 42 | 43.13% | 48 |
| Brian Knight | 34.11% | 62 | 3.45% | 52 | 43.32% | 58 |
| Brian O’Nora | 36.08% | 80 | 3.29% | 43 | 45.17% | 87 |
| Bruce Dreckman | 36.01% | 78 | 4.24% | 76 | 42.33% | 26 |
| CB Bucknor | 30.55% | 15 | 3.55% | 55 | 42.16% | 21 |
| Chad Fairchild | 32.98% | 45 | 2.70% | 19 | 41.95% | 17 |
| Chris Conroy | 28.98% | 3 | 3.71% | 64 | 43.13% | 49 |
| Chris Guccione | 30.19% | 11 | 3.00% | 32 | 43.85% | 69 |
| Chris Segal | 32.43% | 33 | 2.88% | 25 | 43.03% | 46 |
| Clint Fagan | 30.38% | 12 | 2.64% | 18 | 42.70% | 36 |
| Cory Blaser | 33.40% | 51 | 2.89% | 26 | 42.86% | 41 |
| D.J. Reyburn | 33.79% | 59 | 3.37% | 48 | 42.56% | 30 |
| Dale Scott | 31.22% | 20 | 4.03% | 72 | 42.66% | 34 |
| Dan Bellino | 32.81% | 41 | 2.92% | 28 | 42.73% | 37 |
| Dan Iassogna | 37.31% | 84 | 3.57% | 56 | 44.28% | 83 |
| Dana DeMuth | 29.98% | 8 | 4.52% | 83 | 42.80% | 39 |
| David Rackley | 35.28% | 72 | 4.25% | 77 | 43.43% | 59 |
| Doug Eddings | 34.86% | 68 | 2.19% | 8 | 42.33% | 25 |
| Ed Hickox | 34.38% | 66 | 4.33% | 81 | 40.86% | 3 |
| Eric Cooper | 33.43% | 52 | 1.74% | 2 | 41.65% | 12 |
| Fieldin Culbreth | 33.01% | 46 | 3.38% | 49 | 44.16% | 79 |
| Gabe Morales | 32.70% | 38 | 2.58% | 16 | 44.24% | 82 |
| Gary Cederstrom | 31.64% | 22 | 3.63% | 59 | 44.59% | 84 |
| Gerry Davis | 32.36% | 32 | 4.33% | 80 | 43.43% | 60 |
| Greg Gibson | 29.99% | 9 | 3.71% | 65 | 43.81% | 68 |
| Hunter Wendelstedt | 33.66% | 55 | 2.86% | 24 | 43.93% | 71 |
| James Hoye | 29.70% | 6 | 3.85% | 67 | 45.04% | 85 |
| Jeff Kellogg | 30.12% | 10 | 3.65% | 61 | 40.75% | 2 |
| Jeff Nelson | 36.02% | 79 | 2.36% | 11 | 44.10% | 77 |
| Jerry Layne | 35.21% | 70 | 4.61% | 86 | 43.20% | 54 |
| Jerry Meals | 31.86% | 24 | 3.86% | 68 | 42.68% | 35 |
| Jim Joyce | 29.84% | 7 | 4.15% | 74 | 45.05% | 86 |
| Jim Reynolds | 31.23% | 21 | 2.85% | 23 | 42.14% | 20 |
| Jim Wolf | 33.16% | 48 | 3.14% | 37 | 41.05% | 4 |
| Joe West | 32.51% | 34 | 4.54% | 84 | 43.20% | 55 |
| John Hirschbeck | 39.18% | 87 | 2.63% | 17 | 42.56% | 29 |
| John Tumpane | 30.76% | 18 | 3.23% | 39 | 41.44% | 7 |
| Jordan Baker | 32.58% | 36 | 3.30% | 44 | 43.00% | 44 |
| Kerwin Danley | 32.51% | 35 | 3.93% | 70 | 42.34% | 27 |
| Lance Barksdale | 28.95% | 2 | 2.33% | 10 | 41.12% | 5 |
| Lance Barrett | 34.38% | 67 | 2.94% | 29 | 43.96% | 72 |
| Larry Vanover | 33.27% | 49 | 4.09% | 73 | 43.20% | 53 |
| Laz Diaz | 31.80% | 23 | 3.67% | 62 | 41.83% | 15 |
| Manny Gonzalez | 35.27% | 71 | 2.74% | 20 | 43.99% | 73 |
| Mark Carlson | 31.99% | 27 | 3.38% | 50 | 41.49% | 8 |
| Mark Ripperger | 33.99% | 61 | 2.09% | 6 | 44.19% | 80 |
| Mark Wegner | 31.94% | 26 | 3.09% | 34 | 42.57% | 32 |
| Marty Foster | 33.47% | 53 | 3.07% | 33 | 43.75% | 64 |
| Marvin Hudson | 32.19% | 30 | 3.60% | 57 | 41.63% | 10 |
| Mike DiMuro | 35.50% | 74 | 3.21% | 38 | 42.56% | 31 |
| Mike Estabrook | 35.68% | 76 | 2.90% | 27 | 42.82% | 40 |
| Mike Everitt | 33.79% | 58 | 2.06% | 4 | 42.29% | 24 |
| Mike Muchlinski | 33.63% | 54 | 3.27% | 41 | 41.89% | 16 |
| Mike Winters | 32.78% | 40 | 4.17% | 75 | 43.19% | 52 |
| Pat Hoberg | 34.33% | 65 | 2.54% | 14 | 41.56% | 9 |
| Paul Emmel | 32.05% | 29 | 3.87% | 69 | 43.07% | 47 |
| Paul Nauert | 38.63% | 86 | 3.27% | 40 | 42.42% | 28 |
| Paul Schrieber | 30.39% | 13 | 3.10% | 35 | 44.09% | 75 |
| Phil Cuzzi | 33.14% | 47 | 1.74% | 3 | 42.61% | 33 |
| Quinn Wolcott | 33.30% | 50 | 2.81% | 22 | 43.43% | 61 |
| Rob Drake | 33.70% | 56 | 4.57% | 85 | 41.37% | 6 |
| Ron Kulpa | 35.74% | 77 | 2.58% | 15 | 43.01% | 45 |
| Ryan Blakney | 29.20% | 4 | 3.34% | 45 | 43.76% | 65 |
| Sam Holbrook | 32.95% | 44 | 3.65% | 60 | 42.21% | 22 |
| Scott Barry | 32.85% | 42 | 2.95% | 30 | 43.67% | 63 |
| Sean Barber | 32.01% | 28 | 4.46% | 82 | 42.12% | 18 |
| Ted Barrett | 35.09% | 69 | 3.36% | 47 | 41.70% | 13 |
| Tim Timmons | 33.75% | 57 | 3.34% | 46 | 42.75% | 38 |
| Tim Welke | 36.27% | 81 | 3.63% | 58 | 43.47% | 62 |
| Toby Basner | 30.65% | 16 | 2.48% | 13 | 44.09% | 76 |
| Todd Tichenor | 32.35% | 31 | 4.01% | 71 | 44.00% | 74 |
| Tom Hallion | 32.71% | 39 | 4.78% | 87 | 42.21% | 23 |
| Tom Woodring | 24.33% | 1 | 3.85% | 66 | 40.17% | 1 |
| Tony Randazzo | 34.14% | 63 | 3.47% | 53 | 43.16% | 51 |
| Tripp Gibson | 31.03% | 19 | 3.13% | 36 | 43.15% | 50 |
| Vic Carapazza | 34.26% | 64 | 2.74% | 21 | 43.28% | 56 |
| Will Little | 30.53% | 14 | 1.65% | 1 | 44.15% | 78 |
A few disclaimers about these results:
- They are only as good/reliable as the Pitch data in the Game Day data.
- They depend on Zone being an accurate representation of whether the pitch was a ball or strike.
- The current technology only measures where the ball crosses the front of the plate. So, for example, pitchers with great curve balls may throw a monkey wrench into any comparison.
And yes, someone in the not too distant future, a comparable post with these metrics calculated for pitchers and batters is planned.
