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By Jonathan Hale
You often hear that a pitcher with a good reputation or a great career is more likely to get a borderline call from the man behind the plate. It does seem like human nature to be swayed by a big name on the mound, but is it really the case, or does it just seem that way because the better pitchers just hit the corners more often?
Let’s use having won a Cy Young as an easy way of defining a good reputation, and compare the zone of winners of that award to the rest of the league. John Dewan shows an excellent way of measuring strike zones in his article “ Strike Zone: Fact or Fiction”. See his article for full details, but in a nutshell the idea is to find the edge of the strike zone (separately for horizontal and vertical) by finding the point at which half of all pitches are being called strikes.
The results in the above article were for the first half of the 2007 season, so here’s an update of the average strike zone for all pitchers last year. As usual for pitch f/x, the perspective for the following pitches are from behind the plate, with 0.0 being right down the middle.
Horizontal Strike Zone As you can see, there are still a number of pitches down that pitch f/x claims are right down the middle that umpires are calling balls. But what is important is where the curve crosses the 50% middle line. On the right half of the plate, the point where half of all calls were strikes comes out to 0.97 feet from the centre of the plate. On the left, it’s -1.14 ft. This is measuring from the middle of the ball, so to find the actual zone, we have to subtract the radius of the ball the results is 10.19 inches to the right and 12.23 inches to the left. The actual width of the plate is 8.5 inches, but these results are not quite as bad as they seem because we’re only looking at pitches right at the belt, which is where the zone bulges out the most: 
Now on to the vertical results. Pitch f/x operators record them by sight for every pitch, and by their observations last year, the top and bottom of the strike zone for every player was 1.6 and 3.5. However, here’s what the calculation method says:
Vertical Strike Zone After subtracting for the radius of the ball, the crossing points are a bottom zone of 1.64 feet on the bottom and a top of 3.35 – pretty close to what was being manually measured, but about two inches smaller at the top of the zone. Altogether, in inches, the results of the size of the strike zone in 2007 for the league was: Top: 40.19 Bottom: 19.68 Right: 10.19 Left: 12.23
The Cy Zone
Now we’re ready to use this method but only look at a subset of pitchers- those that have won a CY Young award. The current list of active players who had received a Cy Young before the 2007 season is:
Brandon Webb
- Chris Carpenter
- Eric Gagne
- Randy Johnson
- Tom Glavine
- Johan Santana
- Bartolo Colon
- Roy Halladay
- Barry Zito
- Roger Clemens
- Pedro Martinez
- Greg Maddux
- John Smoltz
Here’s their strike zone from right to left: Cy Young Horizontal Strike Zone  That’s a 1.77 foot bottom and a 3.54 top. Altogether, in inches, here is a recap of how the strike zones of the active Cy Young winners stacked up against the rest of the league last year:
| Cy Young
| Rest of League
| Cy Young Bias
| Left
| 13.19
| 12.23
| 0.96
| Right
| 10.91
| 10.19
| 0.72
| Top
| 41.03
| 40.19
| 0.84
| Bottom
| 19.79
| 19.68
| 0.11
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Not as much difference towards the bottom of the zone, but otherwise in 2007 pitchers with the right hardware on their resume had a strike zone that was a little less than an inch larger. Whether this is because they’re better pitchers or more respected is up for debate, but the decisions of umpires do seem to be affected by the man on the mound.
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