Lopez/Mills: Everyone wants to go home during extra innings, maybe even the umps

From Michael Lopez and Brian Mills at FiveThirtyEight on April 18, 2018:

Umps miss balls and strikes all the time. But the strike two in that [Jake] Marisnick at-bat is emblematic of a larger pattern of borderline calls, albeit one that umps probably produce unwittingly: In extra innings, umpires will vary ball and strike calls in ways that tend to end the game as quickly as possible.

To find this pattern, we looked at pitches thrown in the bottom of extra innings, when the game could quickly end. If the away team scored in the top half of an inning and held a lead, as was the case in Marisnick’s at-bat, an umpire hoping for a faster exit would call more strikes, making it more likely that the home team will be sent down quickly. Alternatively, if the home team got a runner aboard, umps would be more likely to favor them by calling fewer strikes, giving the team more chances to get the runner across the plate and send everyone home.

Here’s a chart showing how umps changed their behavior in these situations between 2008 and 2016, a sample of roughly 32,000 pitches.

Read the full article here: https://fivethirtyeight.com/features/everyone-wants-to-go-home-during-extra-innings-maybe-even-the-umps/

Originally published: April 18, 2018. Last Updated: April 18, 2018.