There’s much ado made about the environment at Coors Field. It enhances scoring and batting stats, they say, because the air is thin; therefore, the balls travels further. By that logic, it would also make for some terrible pitchers, since the environment works both ways. Even with the climate-controlled baseballs, the Park Factor is still 107 (where 100 is neutral and anything above favors hitters; Yankee Stadium is a 96).
So let’s look at some home/road splits for the Rockies. My hypothesis: we’ll see a depression of slugging percentage on the road, mainly due to the home run factor. However, we won’t see any correlating trend in batting average and on base percentage. The thin air should only have an effect on balls that leave the park. The results should all even out for those balls that stay in play. That is, if the ball does in fact carry in the thin air, a bloop may become an out, and a fly to center field may carry over the outfielder’s head.
2007 Home: .278/.352/.437
2007 Away: .258/.330/.372
Wow, a 20 point drop in batting average. The OBP correlates, which is to be expected. But I definitely didn’t expect such a sharp drop in batting average. Slugging does take a huge hit, as would be logical. Their doubles match up well — 67 in 36 home games, 66 in 33 road games — but their home runs are wholly disproportional — 35 at home, 18 on the road. Let’s see if we see the same trend over a full season (2006):
2006 Home: .294/.366/.459
2006 Away: .247/.316/.408
Another drastic drop. However, the power factor doesn’t jibe. There was a 47 point drop in batting average, but just a 51 point drop in slugging percentage. That means the isolated power statistics are about even (i.e., the loss in power was merely a loss of singles, not doubles, triples and homers). However, they did hit more home runs on the road (82) than at home (75). Odd.
Of course, I went and looked back even further, because the more home runs on the road stat for 2006 doesn’t make sense.
Okay, so we can see that 2006 was an anomaly, and that the Rockies hit more homers at home than on the road.
But what about visiting teams?
Good question. Let’s flip this model around to look at pitchers.
|Year||Home ERA||Home HR||Away ERA||Away HR|
What does this mean for the Yanks?
Gotta love looking at the 2007 stats, because it shows that the Rockies pretty much suck at home. They give up a lot of long balls, and have a 5.07 ERA. Reinforcing the anomaly of 2006 is the team ERA at home. It was below 5.00 for the first time since…ever.
They give up 0.94 HR/9 at home. The Yanks have hit roughly 1.16 HR/9 on the road. The Rockies have hit nearly double the home runs at home as on the road, while the Yanks maintain a relatively even split (38 home, 37 on the road). Does this mean that we’ll hit 2.32 home runs for every nine innings played at Coors Field? Probably not, but it’s fun too look at.
The Rockies have given up 5.53 runs per game at home, and the Yanks have scored 5.30 runs per game on the road. The Rockies have scored 14 percent more runs at home than on the road. Does this mean that the Yankees will score over six runs per game at Coors (plus the bonus they get from the Rockies pitchers giving up a ton of runs)? Probably not. But once again, it’s fun to look at.
What this basically boils down to is that the Yanks really have no excuse to not take two of three here. I’d say they have no excuse to not sweep, but strange things happen in the game of baseball. They’d have to get really really unlucky to not win this series.
Update by Mike: The drop in BA from home to road is easily explained. If you’ve got DirecTV or mlb.tv or any package like that, be sure to tune into a Rockies’ homeÂ game one night, and pay extra attention to where the outfielders are positioned – they are DEEP. Any balls that are hard hit at Coors – humidor or not – slice through the thin air and more often than not end up at the wall, so the outfielders have to play deep to cut down on all the extra doubles and triples.
But there’s a tradeoff with cutting down on all the extra base hits – lots of little flares and bloopers drop in because the outfielders are playing so deep. Instead of a routine can of corn, you have a have a man at first. Obviously, they don’t have this problem when on the road. The Rockies basically have to pick their poison, do you give upÂ one double or 2-3 singles?
There’s a very interesting solution to whole Coors’ Effect: move the walls in. Guys will still be able to cut down all the doubles,Â but they’ll have a better chance of running down all the little chip shots and bloops that are dropping in for singles now. There may be more homers given up (ok, there will be more homers given up), but they’ll mostly be solo shots rather than the 2 and 3 run blasts that plague the organization now.