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Baseball By The Numbers
By Michael Salfino
June 30, 2006
When Homers Are Fluky
While baseball purists love advancing runners with “productive outs,” do we underestimate the importance of home runs to winning games?
Heading into the weekend, there were four teams currently playing over .600 baseball: the Tigers, Mets, White Sox and Red Sox. The Tigers have hit 30 more homers than they’ve allowed, the Mets 22, the White Sox 17 and the Red Sox just 3.
On the other end of the spectrum, the Royals are minus 50 and the Cubs minus 39. Baseball’s other terrible team, the Pirates, are actually plus 13. Perhaps they’re not as bad as their recent losing streak suggests.
Or, perhaps, home runs can be fluky. Sure, you can limit them by inducing ground balls. But shouldn’t the percentage of flyballs that become homers be about the same for each team? Ballpark factors must be considered, too. But, this year, the team that’s allowed the fewest homers in baseball plays in the thin air of Coors Field (just 59 homers allowed for the Rockies).
Historically, about 10 percent of flyballs become homers. This year, it’s 12 percent. The big outlier on the down side is Toronto, which has allowed homers on 17 percent of flyballs. I’d bet a lot of money that the Toronto staff will be closer to 12 percent going forward, which should translate into at least a few more wins. In the NL, the Cardinals’ staff is most unlucky at 15 percent.
Conversely, the Yankees have been lucky in allowing homers on a league-low 10 percent of fly balls. The aforementioned Rockies, just eight percent.
Individual players can sustain greater variances longer because the sample sizes are smaller. Plus, an individual can make significant improvements that are more likely to be real. The same is true for individual performance declines. Still, when the percentage of fly balls that become homers varies greatly from recent yearly averages for reasons that cannot be attributed to age or injury, it’s wise to expect a regression (or progression) to the mean.
Let’s look at how some hitters and pitchers are doing in this statistic and make some recommendations.
Buy
A.J. Pierzynski, C, White Sox: Last year’s power surge was a result of an increase to 12.2 percent in converting flyballs. This year, he’s back down well below prior norms all the way to 5.3 percent. In that park, Pierzynski should be over 10 percent going forward.
Felix Hernandez, P, Mariners: So unlucky, with 22 percent of flyballs turning into homers. Last year, it was 13.9 percent and it will probably be very close to that level prospectively.
Josh Beckett, P, Red Sox: Remember, Fenway is a very tough park for lefty power hitters so Beckett’s homers allowed should not have gone from about 10 percent of flyballs to 18.5 percent. Expect a second-half correction and significant declines in ERA.
Hold
Michael Young, SS, Rangers: Don’t expect significant homer gains. He’s accelerated his 2005 trend of hitting more grounders and his 2006 percentage of flyballs that become homers (six) isn’t that far off from 2004 (8.6).
Nate Robertson, P, Tigers: He’s been really hurt by the long ball in prior seasons. This year, however, he’s right where you’d expect him to be in our stat, 12.5 percent.
Sell
Brandon Inge, 3B, Tigers: Only has value because of those 16 homers, as many as all of last season. His rate has doubled to 16.8 percent. It’s doubtful that he’s doubled his strength.
Raul Ibanez, OF, Mariners: He’s on pace for 30 homers after hitting just 20 last year. Safeco is a good park for lefty power, but it was last year, too, when Ibanez’ rate was 12 percent (17.3 percent this year).
Brad Penny, P, Dodgers: He’s cut his rate of flyballs that become homers in half, to a major league-low 5.6 percent. This screams “fluke.” |
