Happy Labor Day! Regularly Scheduled Articles Will Resume on Tuesday, September 2.
April 2, 2014
Bonds vs. Pedro, and More Fun with Batter-Pitcher Matchups
As we talked about on Monday, Mike Trout has hit Felix Hernandez very well. After his first-inning home run on Opening Day, Trout is now hitting .441/.447/.794 in 38 plate appearances against Hernandez since being called up to the majors for good in April 2012. The question for the day, then, is this: How well should Mike Trout do against Felix Hernandez?
Which inevitably leads to this: How well would Bartolo Colon do in 600 at-bats against Craig Kimbrel? How many bases would Billy Hamilton steal if every pitcher in the league were Adam Wainwright? But we’re getting ahead of the intro.
To answer the Trout/Hernandez question, we turn to our old friend Log5, a Bill James invention that helps us determine how two teams with different winning percentages would fare against each other, and that can be tweaked slightly to tell us what a hitter of a certain skill level should do against a pitcher of a certain skill level. (Or observed performance level, since we're not regressing to determine each player's true talent over a given period.) If a batter who homers 20 percent more than the league average faces a pitcher who allows 20 percent more home runs than the league average, he should hit even more home runs. And so on. Intro. Words. Segue. Bold text:
Felix Hernandez (2012-2014) vs. Mike Trout (2012-2014)
Most comparable hitter: Matt Holliday (.297/.383/.492)
Most comparable pitcher: Randy Wolf (.313/.370/.510)
So Mike Trout turns Felix Hernandez into Randy Wolf. Felix Hernandez turns Mike Trout into Matt Holliday. See how this works? Onward!