The World's Worst Sports Blog

Home runs and non-homer RBIs May 31, 2016

Neil Walker. Photo: Arturo Pardavila III via Wikimedia Commons.

While at yesterday’s Mets game, a friend of mine pointed out that Neil Walker had a surprisingly high ratio of home runs to RBIs – at the time, it was 12 homers to 23 RBIs, or a ratio of about .522 homers per RBI. That boils down to Walker hitting a ton of solo homers, including the only run scored in yesterday’s game. True, a lot of that is because Yoenis Cespedes tends to clear the bases before Walker gets a chance to drive in the runners, but that does beg the question – what does the typical hitter’s ratio look like?

Of players with 150 plate appearances or more, the surprise leader isn’t Walker, but Curtis Granderson. As a leadoff hitter, that makes sense: he gets more chances than Walker to hit homers with no one one, since he gets an opportunity every game. Grandy’s hit four homers to open the first inning and 5 midgame, including his walkoff against Pedro Baez.

As a curiosity, there are seven qualified batters who have no home runs this season: Cesar Hernandez, Billy Burns, Francisco Cervelli, Austin Jackson, Erick Aybar, Alcides Escobar, and Martin Prado. Escobar is bringing up the rear with 230 plate appearances. Of the top 10 players in HR per RBI, only Walker and Giancarlo Stanton are in the double digits for home runs (each with 12).

The home-run-to-RBI ratio of all batters with 150 plate appearances, as of May 30.

Unsurprisingly, there’s a strong correlation (ρ = 0.78) between HR/RBI and number of home runs; longball hitters tend to hit them whether there are runners on base or not. Probably the strongest statistical interpretation we can offer here is that RBIs are a pretty lousy way to evaluate hitters; they contain little information that simply measuring home runs, slugging average (ρ = 0.46) or OPS (ρ = 0.315) doesn’t offer.

It’s possible that a high HR/RBI ratio would indicate that a batter performs poorly in the clutch: the player doesn’t hit homers with men on base. In order to justify that interpretation, though, we’d need significantly more evidence and to do some statistical testing to see if he really did hit differently with runners in scoring position than without. It may be that, like Walker, there just aren’t that many opportunities. The only time this seems to be a red flag statistic would be for a hitter who plays with a team full of high-OBP, low-SLG hitters, indicating that there are usually men on base and he doesn’t drive them home. Otherwise, for guys like Walker and Stanton, it’s just a fun eye-bugging stat.