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Tuesday, August 12, 2003

But How are the Cigars?

The Coors Field Humidor, 18 months later.

There are signs that the Rockies’ management wishes that Coors Field was
not a high-scoring hitter’s paradise, that their ballpark produced games
more like normal MLB parks do.  But nothing can be done about the thin
air of the high Rocky Mountain altitude - thin air doesn’t permit breaking
balls to break the normal amount but does allow balls hit into play to zip rapidly and
relatively unimpeded, and is, of course, not willing to negotiate about
such attributes.

Thus, as a whole slew of national sports media articles testified, between
the 2001 and 2002 seasons, the Rockies managements apparently installed a
humidor for baseballs at Coors.  The thinking went that a slightly soggier,
heavier ball would give pitchers a better grip when throwing, could perhaps
enable breaking balls to actually do their thing, and would enable balls
hit to absorb more impact, thus traveling less far and less fast.  All of
this was supposed to lead to lessen offense at Coors to the level one
would find at most other MLB parks.

The many humidor articles predicted that its use might change baseball in
Colorado.  And since the start of the 2002 season, things have indeed
changed there in a big way.  For example, the Rockies’ home field
advantage, always unusually large, has skyrocketed:

** Total Games **
Coors   Road
558   558   before
135   140   after

** Rockies’ Winning Percentage **
Coors   Road   Coors effect
0.566   0.414   +0.152 before
0.630   0.314   +0.315 after

[“before ” signifies 1995-2001 for winning %, total G, and R/G, and
1996-2001 (could not find home/road break-downs for 1995) for AB, H, HR,
BB, and K information.  “after ” is the 2002 season and this 2003 season
through Aug 2]

What has been the cause of this jump in home field advantage since the
start of the 2002 season?  One factor is that Colorado hitters are enjoying
pretty much the same gigantic Coors field offensive boost after the
humidor’s installation as they did before:

A = Runs per Game
B = Walks as Percentage of PAs   [BB/(BB+AB)]
C = Strikeouts as Percentage of PAs   [K/(BB+AB)]
D = Home Runs as Percentage of Balls Put In Play   [HR/(AB-K)]
E = Base Hits as Percentage of Balls Put In Play and In The Park

Stat   Coors   Road   Coors effect
A     7.12   4.16   +71% before
      6.44   3.69   +75% after
B     8.92%  8.21%  +9% before
      9.86%  8.58%  +15% after
C     13.89%  18.13%  -31% before
      15.46%  20.31%  -31% after
D     5.21%  3.58%  +46% before
      4.55%  2.87%  +58% after
E     35.54%  28.42%  +25% before
      34.33%  28.23%  +22% after

Since the humidor went on line, not much has changed for Rockies
hitters; they have continued to have that Silver Bullet jet-rocket boost to their
mashing when batting at home (hits down a touch, homers, walks, and total
runs scored up).  During the same 275 games, however, the “Coors effect” experience by visiting teams has fallen back down to Earth:

A = Runs per Game
B = Walks as Percentage of PAs   [BB/(BB+AB)]
C = Strikeouts as Percentage of PAs   [K/(BB+AB)]
D = Home Runs as Percentage of Balls In Play   [HR/(AB-K)]
E = Base Hits as Percentage of Balls In The Park and In Play [(H-HR)/(AB-K-HR)]
Stat   Coors   Road   Coors effect
A     6.71   4.66   +44% before
      5.73   5.18   +11% after
B     9.55%  10.23%  -7% before
      8.53%  9.89%  -16% after
C     15.11%  16.34%  -8% before
      15.62%  14.20%  +10% after
D     5.29%  3.74%  +41% before
      5.19%  3.77%  +38% after
E     33.32%  30.02%  +11% before
      30.69%  30.38%  +1% after

While Colorado hitters continue apparently as before, coming to Coors has
lately has resulted in visiting teams collecting fewer base hits of all types, fewer
walks, and a lot more strikeouts than during the pre-humidor era.  To put it another way,
before the humidor was installed, in an aggregate of 972 games and over
37,000 PAs from 1996 to 2001, opposing teams showed a Coors field effect of
+29% on hits per game and +1% on BB per K In 275 games and about 10,000
PAs since the installation, visiting hitter’s “Coors Effect” has fallen to
+10% on hits per game and -28% on BB per K.  How do you end up with worse
control of the strike zone in a park without breaking balls?

It is odd to see Colorado pitchers (like Jose Jimenez and Denny Stark last
year, Jason Jennings, Javier Lopez, and Darren Oliver this year, and Brian
Fuentes both years) showing home/road splits that look as it they pitched
half their games at Pac Bell or Chavez Ravine, instead of in the hitter’s
paradise that they do.  It could be that Clint Hurdle and
pitching coach Bob Apodaca have in the last fifteen months instilled in
their pitchers some secret or two as to how to throw effectively at
altitude or with humidor-ed balls that visiting teams have not yet caught
on to.  But, even so, looking at the numbers, I can’t help but wonder if
the Coors field staff have not developed a plan as to getting more soggy
low-offense balls out to the home plate umpire during the tops of innings,
and then break out good ol’ fashioned high-flying normal balls when the
Rockies come to bat.

Sinister conspiracy or not, something seems to be going on.  The one thing
I can say for certain is that, as a Giants fan, I am tired of Coors games
during the last year-and-a-half where the Rockies hitters have come on like
Ah-nold while The Boys in Orange and Black end up looking like Woody Allen
at the plate.  My only solaces here are (1) that the Dodgers and
Diamondbacks have been equally dominated at Coors, and (2) how eminently
beatable the Rockies have been on the road.


Adam Coutts Posted: August 12, 2003 at 06:00 AM | 9 comment(s) Login to Bookmark
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   1. The Original Gary Posted: August 12, 2003 at 02:33 AM (#612563)
I don't think that comment really flies. The fact is that the Rockies have been a much BETTER team this year than they had at any time in the prior recent past. They were poor last season, but even then were fairly consistent with recent seasons just before that.

Their .490 winning % was compiled largely in the mid-90s when their talent level was demonstrably better, if not dramatically so.
   2. Shaun Payne Posted: August 12, 2003 at 02:34 AM (#612567)
I'm not sure, but it seems like the Rockies are pitching better than they have in recent years, which may be why the home-field advantage is greater for the Rockies. The Rockies' hitters are better at home than on the road and the pitchers aren't that much worse. But other teams' hitters, while better, don't take advantage of Coors like the Rockies do because maybe the Rocky hitters "know how" to hit at Coors and other teams' pitchers are worse at Coors and worse than the Rockies' pitchers because the Rockies' pitchers know how to deal with Coors better than their opponents.

I haven't looked at any numbers, so this is just a theory, but who knows. It's based on the observation that the Rockies seemed to be getting better pitching than they have in other years. Who knows what's going on?
   3. Adam Coutts Posted: August 12, 2003 at 02:34 AM (#612568)
I am not so interested in the Rockies' aggregate home/road performance. As my article expresses, what is most compelling to me is that the humidor's installation seems to have coincided with a dramatic change in the outcome of games involving Colorado when broken down by home and road. The 2001-02 offseason seems to be a turning point, after which the Rox have risen to being almost unbeatable at home ? they seem to have some strange "advantage". And they are all the putrid on the road ? showing that the team's actual talent level is lower (man, whatever "advantage" they have at home must be powerful to help such a truly bad team) or that they have grown lazy, dependent on their powerful "advantage" to help them win and unable to win without it. My admittedly biased sense, watching and listening to Giants games, is that the "advantage" consists of some sort of funny business, perhaps involving the humidor ? since April 2002, at Coors, it's been like the hosts and the visitors are playing two different parks. But, yes, it could be that the advantage is 100% clean and merely involves pitchers who have learned how to pitch at altitude while at Triple A (but, who it must be pointed out, have not acted like "better pitching" while on the road). But half the innings in 2001 and 2002 were pitched in the same proportions by the same pitchers (Chacon, Hampton, Jennings, Jimenez, Neagle, Nichting, Speier, Thompson) and something big changed between those two years in terms of their home-field performance. And I also noticed that the Giants absolutely dominated at home in 2000, when Pac Bell first opened and visitors hadn't yet figured out its quirks the way the home team had, but that that advantage has decreased over time with vistor's familiarity. If the Rockies have figured out some secret to pitching well in their park, it seems strange that the rest of the NL West has not caught on as well and brought Rockies' offensive numbers down. Also ? thanks everyone for their comments, and thanks for the props, Arvin.
   4. Adam Coutts Posted: August 13, 2003 at 02:34 AM (#612575)
maximize that home field advantage as much as possible to cancel out the road impediment.

Mr. Guttridge: It would seem that the Rox have found just such a way to maximize their home-field advantage, starting at the beginning of the 2002 season. Since then, the numbers show that they have found a way to keep the whole of the Coors advantange for their own hitters, while almost totally negating it for visitors. You seem to be a Rockies insider, and someone who seems to have put a lot of thought into such matters. How do you think they have done it?

Anecdotally, the reason pitchers cite for any improvement in the new playing conditions is due to the feel they have for a ball that has not dried out in the semi-arid Colorado climate.

Mr. Nelson: visiting pitchers have shown no improvement since the humidor has been put in. Only Rockies pitchers have (and their improvement has been sizable).
   5. villageidiom Posted: August 14, 2003 at 02:34 AM (#612585)
If the reduced gravity effect is that small, then there would probably be an almost insignificant difference in a ball thats thrown with 20% humidity and a ball thrown with 75% humidity over the course of 60 feet. And this is the only way the humidor could really effect movement on pitches.

Perhaps the increased humidity would improve not the movement, but the accuracy. If the ball is drier it might make it more difficult to grip in general, which will make it more difficult to throw a pitch exactly where you want it. With the more humid ball it might improve accuracy.

Of course the numbers above do and don't support this, with opposing hitters drawing fewer walks and Rocky - is that the correct singular? - hitters drawing more.

Then again, maybe it's just a matter of what you're used to. Rocky pitchers are used to having greater control at home, and they walk fewer batters there; opposing pitchers are used to having pitches break... but they were always used to that, so they should walk about the same as before. If their expectations changed (i.e. if they bought the hype that they'd have better movement and ended up throwing more breaking stuff than in the past) they'd walk hitters more often.

So part of it might be science, and part might be erroneous perception of science.

My point is, at this rate you're not going to be able to tell what the hell kind of ball your using by the second or third inning. You would have to not only keep track of # of foul balls in relation to number of humidor and non-humidor balls given to the umpire, you'd have to keep track of weather the umpire pulls a humidified or non-humidified ball out of his pocket, which is impossible.

If there is enough of a difference between a humid ball and a dry ball, the pitcher should be able to tell the difference just by gripping it. (Insert Mike Piazza response here.) No need to keep track of anything.

And if he can tell the difference, all he has to do to get a dry ball out of the game is to throw a pitch in the dirt. Every time I've seen a ball hit the dirt this year, the umpire removes it from the game. Not that you want to start off the inning with a ball in the dirt, mind you... but if they want a ball removed they can get it removed. (Insert John Kruk response here?)
   6. Steve Posted: August 14, 2003 at 02:34 AM (#612594)
It is easier to get rid of a ball that you don't like than that (throw it in the dirt), just ask the umpire to give you a different ball. In high school games (where foul balls are returned) a smart pitcher (or at least one that needs the help) will use the least slippery ball and the one with the biggest seams all the time. You keep track of the best one and when it is returned ask for it back. It isn't necessarily the physics of the seams or the humidity it is the pitcher's feel/grip on the ball. When a pitcher goes to his mouth on cold nights it isn't to warm up his hand it is too apply humidity to it.
   7. Adam Coutts Posted: August 14, 2003 at 02:34 AM (#612597)
Let's break down the actual mechanics of this alleged ball-mishandling to get a sense of the practicality of such a matter.

I appreciate the cogent, informed, and interesting examination of the actual mechanics of any possible humidor hijinx. But I also think that an unfair system (humidored balls to home pitchers, dry balls to visiting pitchers) wouldn't have to be 100% perfect and infallible to show the effect that I'm noticing. Looking at the numbers percentage wise, the Rox have kept their total home/road Coors scoring bump equal, pre- and post-humidor, by raising walk and HR totals, but their home/road Coors effect on base hits as percentage of balls put in play has dropped 3%. This is less than the 10% drop shown by visitors, and this smaller Rockies' hitter's drop-off could be the effect of the visiting pitchers getting some of the damp balls when end-of-inning effects can't be avoided.

I don't think that I need to underline the fact that baseball has a rich and varied history of cheating, both individual *and* institutional:

The far more compelling problem for sabermetricians would be to explain the current Rockies home vs road winning percentage (see the current Baseball Prospectus article), although apparently that doesn't interest you

But it does. I am intrigued by the idea that current crop of young Rox pitchers are doing better at Coors now then past Rox pitchers did because the new guys are survivors of the thin air of AAA Colorado Springs before coming to The Show, but that their altitude-attuned pitching just doesn't adjust well for the road. But I don't fully buy that line. Here is how it alternatively seems to me:

As Bill James found in the eighties, a typical average ballclub will win .500 of their total games, but that this will break down to .450 on the road and .550 at home. Home park effects average out about +.100, and come from having a team built around the quirks of one's home park, from the support of the home team, from players enjoying sleeping in their own beds, and probably other factors.

The Rockies, during the first seven years of their existence, showed a .414 winning pct at home, and .566 on the road. They were a aggregate basically middle of the road team (.490 total winning pct), with an unusually large home/road split (+.150), because they played in a unique environment that was difficult to adapt to or from.

The Rox home/road winning split has been much larger in 2002-03, as I showed it has been around +.300. My hypothesis to explain this starts with assuming that the Rockies of the last two years have been a fundamentally terrible club. They have a .314 road winning percentage, which is worse than the Tampa Bay's .324, and Todd Helton and Preston Wilson's road slugging %s in 2003 are worse than JT Snow, Pedro Feliz, or Benito Santiago's (and that's not to pump up those three Giants). As I've stated, I suspect however that the Rockies mask their utter suckiness by cheating with the humidor and thus denying visitors the benefits of the Coors batting-boost effect when playing there. I posit that, if the Rockies didn't cheat, and enjoyed their un-cheating natural previous +.150 home park effect, they would be .465 at home the last two years, rather than .630. This would leave them at .390 total winning percentage, which would be embarrassing, be not likely to bring as many paying customers out to the ballpark, and which might call for some unusual measures.

That's my guess. I actually hope that the numbers are pointing to something less machiavellian, but they do seem to be pointing to something.
   8. Adam Coutts Posted: August 15, 2003 at 02:35 AM (#612635)
Thank you Mr. Guttridge for intelligent and thought-provoking discussion. I was hoping that at least one Rockies fan would make some comments so as to provide a different point of view.
   9. Greg Pope Posted: August 17, 2003 at 02:35 AM (#612668)
I'd like to make two points about the possibility of the Rockies providing different balls for the home vs. away teams. I'm also going to refer to the humidified balls as "wet" and the non-humidified balls as "dry". I know that they're not really wet, but it makes it easier to type.

If true (and wet vs. dry balls make a difference), it would certainly have a measurable effect on the hitters. Have you ever noticed how many balls go out of play in an inning? Sure, the umps may throw a ball out of play if it goes in the dirt, but virtually every foul ball is taken out of play. Rocket foul shot down the line? The ball boy gets the ball and tosses it into the dugout, not back to the home plate ump. Lazy fly ball that lands just out of reach of the right fielder? He picks it up and tosses it into the stands. Foul straight back to the netting? The ball boy runs out, grabs it, and takes it back to the dugout. In none of these cases do the balls get back to the ump. And, of course, there's all the foul balls that go into the stands.

You don't have to try to get rid of baseballs. If the ball boys were constantly bringing out wet balls for the opponents and dry balls for the Rockies, I would guess that the Rockies would be hitting with a dry ball for at least 90 percent of their at bats, and the opponents would only get the dry ball 10 percent of the time.

Now my second point. If the Rockies were getting away with this, I think that the effects would definitely show, as I said. However, there's no way that this would actually be kept secret. Think about who would have to know about it. It would take someone on the level of at least manager, if not GM, to even think about implementing it. Then the people who store the balls have to be in on it. Also, the ball boys have to be in on it. How old are these guys, 14? How many are there? A group of 5-6 14-year olds could not keep this secret. Several of them would have told their friends. A few probably would see how much the story would net them from the local newspaper, or Baseball Prospectus. And we can't forget about the pitchers. Can they feel the difference between a wet ball and a dry ball? If so, now you've got the entire Rockie pitching staff in on the cheating. Not just a few guys, but every pitcher who's been called up from the minors. Even if they kept it a secret when they were on the team, haven't any of these guys left the team? Lastly, what about the opposing pitchers? They'll be getting a sampling of mostly dry, but a few wet balls. None of them have said anything?

I don't buy it.

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