Root, root, root for the hometown

Mar 23, 2023 - 3:30 PM

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Top prospect Anthony Volpe’s torrid spring has endeared him to Yankee fans. In 39 at-bats, the 21-year-old has slashed .308/.438/1.028 and chipped in five steals without being caught. Aside from his performance though, the youngster’s upbringing in nearby Somerset County — where the Yankees’ Double-A affiliate resides — has him poised to become a hometown fan favorite.

At the same time, it’s hard to say whether Volpe’s proximity to his childhood home will be anything more than a fun fact. On the one hand, it’s nice to have friends and family to cheer you on at home and to hang out with post-game. On the other, those extra sets of eyes can create more pressure on top of New York’s already-bright lights. Will those opposing forces cancel out the impact of playing for the team he grew up with?

I took a crack at answering this question with an assist from Stathead. There, it was easy to add a column for birthplace to any query. While not the perfect proxy for hometown, it was the most readily available. There will inevitably be some players in the dataset who moved away from their birthplace (for example, see: Rodriguez, Alex), but the hope is that they retained some attachment to their initial dwelling nonetheless.

Last year, there were 249 hitters with at least 300 plate appearances who played for one team the whole season. To account for players born internationally or far from every American stadium, I created a variable that recorded how far their home park that season was from the closest park to their birthplace. I found that, for players born further than 750 miles (in absolute terms) from their home field, the distance-from-closest-park variable didn’t have any effect on performance. However, for players born closer than 750 miles, it was negatively correlated with performance:

In other words, once you get far enough from home, any extra distance from the closest park to you doesn’t matter very much. But when you’re close, if you can shorten the long drive a bit, it seems to go a long way. Plus, the closer you get to home, the closer you get to your favorite team and that team’s division rival. Think of it this way: Volpe was born about 40 miles from Yankee Stadium and 275 miles from Fenway park. Those last 235 miles probably meant a lot to him.

I know this effect is hard to separate from other intangibles, but hopefully I can quell some of those worries because I found that it stood for the 233 hitters with at least 300 plate appearances in the 2021 season as well:

It’s a little bit smaller, but definitely still there. So that’s good news for Volpe, right? Well, one question remains: does Yankee Stadium have any special effect on this relationship? Does it nullify or enhance the hometown advantage?

Largely, it seems to nullify it. I gathered 236 Yankees position player seasons, beginning in the Live Ball era (1920), each being the first time that a player reached 300 plate appearances in pinstripes. Below, the two regression (dotted) lines are more similar and horizontal than the pairs from above:

If you’re wondering what that cluster on the right is, it’s players from California, who make up a sizeable proportion of all big leaguers. There isn’t much data between the California cluster and the one on the left because not too many major leaguers come from the Midwest. Separating the Californians out from the rest of the pack didn’t change the relationship, though; neither did removing the Babe, who is about as much of an outlier as you’ll ever see. I also tried controlling for age and season effects — they were both insignificant.

So, Volpe’s proximity to home shouldn’t impact his performance one way or another if he does end up breaking camp this year. Overall, though, it’s worth thinking about why Yankee Stadium does seem to mitigate the impact of playing nearer to home aside from the intensity of the media climate. One reason might be that there is an alternative team close by in the Mets — some so-called hometown players may have actually grown up donning orange and blue caps. The Yankees status’ as a polarizing franchise, the “Evil Empire,” may also render them less well-liked among fans of teams in neighboring cities than usual.

Further investigation is needed to determine the true causes. In the meantime, here’s to hoping we see Volpe in the majors sooner rather than later.