While Command+ attempts to provide a more complete and accurate examination of a pitcher’s command, Stats Perform’s Whiff+ can give a closer look at a pitcher’s stuff by determining the rate at which he generates swings and misses.
Whiff+ was developed as a tool that enables analysts to compare players of different years on the same scale, which is something other swing and miss rate statistics aren’t able to accomplish. How is this done? Whiff+ is based on the league average pitch type for that season. Understandably, whiff rate has been steadily trending upwards as the percentage of all plate appearances resulting in a strikeout has risen in 14 consecutive seasons. Whiff+ adjusts for that.
Let’s say the average fastball has a swing and miss rate of 8% and a pitcher coaxes a whiff on 10% of his fastballs. By this, we can assess that he has a Whiff+ of 125 – 25% above the league average.
The analysis is done across a pitcher’s entire repertoire to determine a weighted average, because whiff rate increases dramatically for some pitch types like sliders and splitters. The goal of Whiff+ is to discover how good a pitcher is at generating whiffs based on his pitch types.
Here are the top starters and relievers in Whiff+ in 2019:
|7||Lucas Giolito||White Sox||131|
2019 Whiff+ relief pitching leaderboard (minimum 250 PA faced):
It’s not surprising to see Gerrit Cole and Josh Hader top these rankings by wide margins. Hader easily led the majors in both Whiff+ among pitchers who faced at least 250 batters and strikeouts per nine innings (16.4) among those with at least 75 innings in 2019.
Cole went 20-5 with a 2.50 ERA and an MLB-best 326 strikeouts. He also finished second to Hader in SO/9 (13.8) among pitchers with at least 75 innings.
We have always known that not all balls and strikes are equally effective (or ineffective), but now we have more tools to measure the difference in effectiveness for every pitch.
Advanced analytics and data analysis provided by Lucas Haupt