From J.P. Hoornstra at the Los Angeles Daily News on December 6, 2018, with mention of SABR member Meredith Wills:
In May, Major League Baseball commissioned a team of researchers to investigate the reasons for a spike in home runs that began in 2015. Their study concluded that the extra home runs could be attributed, in part, to a change in the aerodynamic properties of the baseball itself. The MLB-record 1.26 home runs per game in 2017 were helped by a renewed focus on launch angle, to be sure. But the baseballs helped too.
Maybe you remember the fallout that ensued. MLB committed to more stringent oversight of Rawlings’ plant in Costa Rica, where its baseballs are manufactured. Minor League Baseball announced that its two Triple-A leagues – the Pacific Coast League and International League – would begin using major league-quality baseballs in 2019. And while MLB’s committee couldn’t determine why the ball’s aerodynamic properties had changed, an independent study conducted by Dr. Meredith Wills suggested the laces had thickened by 9 percent. A physical culprit, it seemed, had been identified.
A local mathematics professor named Jason Wilson monitored this fallout with great interest. A phenomenon that seemed far removed from the Biola University baseball fields was actually right up his alley.
Read the full article here: https://www.dailynews.com/2018/12/05/whats-in-a-pitch-a-biola-statistician-connects-a-change-in-the-baseball-to-movement/
- Related link: Jason Wilson and Jarvis Greiner presented on the Quality of Pitch metric from the 2015 SABR Analytics Conference
Originally published: December 6, 2018. Last Updated: December 6, 2018.