Expected Passed Ball & Wild Pitch Model

Summary

Model the probability of each pitch being a passed ball or wild pitch (PBWP) based on pitch tracking and game state data. 

Inputs

This model is based on pitch results from 2019-2023 MLB regular season, using the following factors:

• Pitch location

• Pitch velocity

• Pitch type

• Count

• Batter hand

• Pitcher hand

• Men on or bases empty

• Swing or take by batter 

Key Metrics

PBWPAA - Passed Balls + Wild Pitches Thrown Above Average - 0 is neutral

PBWP+ - Passed Balls + Wild Pitches Thrown Rate vs. Average - 100% is neutral

For each of those, the pitching perspective indicates whether the pitcher has thrown more PB/WP than expected by the model. The catching perspective indicates whether the catcher has prevented more PB/WP than expected by the model.