This analysis discusses the problem that occurs with a two-dimensional strike zone graphic’s attempt at representing a 3D entity. Article:
Umpires are trained to call balls and strikes based on the rulebook’s 3D zone that includes the area over home plate between the batter’s hollow of the knee and midpoint between the top of the uniform pants and top of the shoulders.
However, the electronic PitchCast graphic generated for broadcast depicts a two-dimensional strike zone that neglects to account for the depth of home plate.
This problem is primarily caused by two factors.
First, the 2D graphic is designed as an easy-to-consume property for baseball fans. It’s meant to take the analysis and guesswork out of ball/strike adjudication, meaning it’s a simplified version of the strike zone that is not accurate in the 3D space.
Second, the StatCast data capture point that feeds PitchCast (Pitch f/x that gave way to TrackMan which will give way to Hawk-eye) only captures data at and in front of home plate. With the computer failing to capture data beyond the front edge of home plate, it misses out on the bulk of the strike zone – its depth (the robot is essentially limited in its ability to accurately see a baseball beyond the front edge of the plate, to the capture point is put in front of the plate in order to minimize capture error). Furthermore, the pfx_x (pitch break) variable is captured at a distance of y=40 feet yet the pitcher’s plate is 60 feet, 6 inches from home plate.