Plate Discipline (O-Swing%, Z-Swing%, etc.)
Description:
If your favorite player has a bad walk rate, why is that? Have you ever wanted to know if a player is good at recognizing the strike zone? Fear not, because Plate Discipline statistics are here! FanGraphs explains these about as succinctly as possible:
- O-Swing%: The percentage of pitches a batter swings at outside the strike zone.
- Z-Swing%: The percentage of pitches a batter swings at inside the strike zone.
- Swing%: The overall percentage of pitches a batter swings at.
- O-Contact%: The percentage of pitches a batter makes contact with outside the strike zone when swinging the bat.
- Z-Contact%: The percentage of pitches a batter makes contact with inside the strike zone when swinging the bat.
- Contact%: The overall percentage of a batter makes contact with when swinging the bat.
- Zone%: The overall percentage of pitches a batter sees inside the strike zone.
Context:
Here are the league averages for each of these statistics for 2009:
| O-Swing% | 25.1% |
| Z-Swing% | 65.9% |
| Swing% | 45.2% |
| O-Contact% | 61.8% |
| Z-Contact% | 87.8% |
| Contact% | 80.5% |
| Zone% | 49.3% |
| F-Strike% | 58.2% |
Things to Remember:
- These statistics are useful for evaluating hitters and pitchers, but are included under “Offense Statistics” because that is the area they are most commonly used for analysis.
- Baseball Info Solutions (BIS), where FanGraphs gets this type of data, changed how it calculates these statistics over the years. When looking back at plate discipline numbers from 2002 or so, beware that the league averages may be very different than what they are today.
Links for Further Reading:
Plate Discipline Stats – FanGraphs
