In the 2015 World Series, the Fox announcers are making a big deal that the Royals are better contact hitters than the Mets. What does that mean? One interpretation is that the Royals are less likely to miss a pitch (a whiff or swinging strike) in a swing. That raises the obvious question: Are the Royals hitters more likely to whiff on a swing than the Mets hitters in this Series?
This question is easy to address from the PitchFX data. Here’s what I did.
- Using Carson’s PitchRx package, I downloaded the PitchFX data for the first four games of the World Series.
- For all hitters, I collected the number of swings, the number of “swinging strikes”, and computed the fraction of whiffs.
- I want to only include hitters who play regularly (not pitchers), so I looked only at the hitters who have had at least 10 swings during the series.
- In the following graph, I use a Cleveland-style dot plot to graph the whiff rates (number of misses divided by the number of swings) for these batters with at least 10 swings, color coding the dots by the team.
What do we see?
- First we see much variation in these whiff rates from Mike Moustakas (only 1 whiff in 35 swings for a 3% rate) to Kendrys Morales (7 whiffs in 17 swings for a whiff rate exceeding 40%).
- Comparing the two teams, the whiff rates are pretty comparable. For example, of the five highest whiff rates, 3 are Mets and 2 are Royals players.
- This does not mean that the Royals are not better contact hitters since a “swing and miss” is a function of the hitter and the pitcher. It is very possible that the Mets pitchers are better in inducing swinging strikes (the Mets pitchers have higher strikeout rates, for example), and so the Royals better ability to make contact is mitigated by the Mets’ pitching.