How about that.

Petco. Wow.

Yankees lead the AL in home runs and Phillies lead the NL in home runs. What’s the over/under for home runs hit in the new Yankee Stadium this weekend?

PG: Three games, I’m taking 16. Buster Olney has been pointing out that they’re going to pass last year’s totals in the old [Yankee] Stadium by about June 15. I’m tired of people saying that it’s too early and we don’t have enough games.



We have enough games and it wasn’t a very well-planned ballpark. Any player will tell you that [the new Yankee Stadium] has become one of the biggest jokes in baseball.

Please retire Peter Gammons.

Yankee stadium boosts home run rates

Well, be honest my friend. ESPN's data shows the New Big Bedpan in Da' Bronx as easily the #1 HR park in all of 'ball.
That's what everybody was carping and kevetching about, no?

That's what everybody was carping and kevetching about, no?

I'm just one person (and not a Yankee fan), but that's what I find displeasing about the new ballpark. The fact that the park supresses other kinds of offense actually makes the park worse, in my mind.

Clay Davenport showed a few years back that one-year measurements of park effects are less useful, in accounting for park effects, than the stopped-clock measurement that every park is the same. We need to wait a few years before we have good data on NYS.

Something seems amiss in Cincinnati.

I agree with JRE on the aesthetics. If NYS is what it was measured to be in 2009, it's going to produce some very unattractive baseball.

(I believe this was Bill James' stance in the newer historical abstract. Baseball is most exciting when the ball is in play, so we should aim at reducing the three true outcomes. An enlarged strike zone combined with restrictions on thin-handled bats would probably do great things for the game. Sadly, what I think makes the best baseball isn't necessary what the lords of baseball are trying to achieve.)

since when did Progressive Jake field become such a pitchers park? That suppression of HRs seems historical.

(and yes, I realize it's only one year of data)

Ignoring the SSS issues, and ignoring the aesthetic aspects (of which i agree w/ #5 and #8), this is good news for the Yankees. Obviously teams benefit from pitcher parks (less innings, etc), but with the yankees, whose money can more easily buy older/slower/power guys, this type of stadium should benefit them even more.

From my THT Annual article:

Home runs hit to right and right-center field at Yankee Stadium, 2009

Before June 1, 2009:
Games: 23
NYY HR/HR per game: 32 / 1.39
Visitor HR: 20 / 0.87
% HR's by NYY: 61.5%
NYY Home Record: 14-9 / 0.609

On and after June 1, 2009:
Games: 58
NYY HR/HR per game: 67 / 1.16
Visitor HR: 24 / 0.41
% HR's by NYY: 73.6%
NYY Home Record: 43-15 / 0.741


2009 Regular Season:
Games: 81
NYY HR/HR per game: 99 / 1.22
Visitor HR: 44 / 0.54
% HR's by NYY: 69.2%
NYY Home Record: 57-24 / 0.704

The Yankees figured out how to clamp down on their opponents' deep fly balls to right field, while maintaining their own ability to exploit the short porch. This was most likely a combination of more innings being thrown by better and/or healthier pitchers, and conscious effort to steer fly balls towards the deeper left field.

For anyone interested in the stats, if you run a 2-sample Poisson test on the HR rates for the Yankees and their visitors for these two time periods, you get a p-value of 0.03 for the visitors (indicating a strong likelihood of a change in the visitors' HR rate to RF/RCF before/after June 1st), and a p-value of 0.40 for the Yankees (indicating no significant change in their HR rate). Or in other words, the visitors stopped hitting HR to RF/RCF, but the Yankees didn't.

The Yankees learned how to leverage the idiosynchrasies of their park, while (unsurprisingly) their visitors did not (or could not). If they hadn't, the HR totals there would have been even higher than they were...

Park effects for walks: How does that work?

Park effects for walks: How does that work?

Same way every park effect works - compare home rate to road rate.

Park effects for walks: How does that work?

Quality of the hitters' backdrop, I assume.

I ran a rgereesion of the runs park factor against the pieces. The R2 was .82.

In it, the Yankee Stadium 'projected' park factor by the pieces was higher than Citi (Mets) by .993 (rank of 16/30) versus .943.

Eiuther Yankee Stadium causes people to not advance on bases, or get thrown out, or maybe teams left a lot more people on than expected. Just looking at the data, one could observe that a park that improves home runs by a lot and walks by some, but is fairly neutral on hits overall (lowering , should not be a strong run supressant.

Biggest diff positive was Wrigley (how can it be 1.146 when no piece is really high?) and negative is Miller (Milwaukee)

Park effects for walks: How does that work?

Quality of the hitters' backdrop, I assume.

Coors field is pretty consistently hitter-favorable when it comes to strikeouts, too. I wonder if the sunshine has anything to do with it as well.

The Yankees figured out how to clamp down on their opponents' deep fly balls to right field, while maintaining their own ability to exploit the short porch. This was most likely a combination of more innings being thrown by better and/or healthier pitchers, and conscious effort to steer fly balls towards the deeper left field.

I'm really interested in this research, and I certainly think there are interesting things to be learned from studying in-season numbers and the effects of scouting and pitching strategy, but I'm not yet sold on the argument you presented here. (And, yeah, I'll be reading the full one in the THT annual this spring.)

To the degree that the pre- and post-June 1st splits are a function of broadly superior pitching, then "figuring out" has nothing to do with it - no one needs to "figure out" that good pitching is good. It's only to the degree that the splits are not a function of the quality of the pitchers that you've found something cool.

This would be a hard thing to isolate in part because I assume that good pitchers are going to be better at executing a strategy of minimizing flyballs to RF. But I'd be interested to hear how (or whether) you tried to isolate that.

Same way every park effect works - compare home rate to road rate.

No, I understand that. But this is where every park should be the same, with maybe a minor variance based on mound differences; batter's eye, as No. 14 suggests; and umpires. That the spread is as much as it is seems to undermine the other park data.

Park effects for walks: How does that work?

Batters eye should affect the ability to draw a walk as much as it does the ability to see the ball for the purpose of hitting it.

I love the wild variance in park effects on triples: from 1.771 in Coors to .500 in NYS. An obvious small sample size issue: only one year, and very few triples per game. If it holds up, though, another data point about how baseball in NYS might be kind of boring going forward: lots of homers and walks, very few doubles and triples.

The numbers for Skydome are interesting to me: the park plays as average in everything but hits, which it suppresses more than any park not named Petco.

No, I understand that. But this is where every park should be the same, with maybe a minor variance based on mound differences; batter's eye, as No. 14 suggests; and umpires. That the spread is as much as it is seems to undermine the other park data.

I'd imagine that, when given multiple years of data, the spread would be much closer. One year is a very small sample that can contain a lot of noise.

I suspect a big factor in Coors' pf for triples is that left-center is so deep. Both RHB and LHB's can hit triples to that spot, and the player doesn't need to be that fast, either.

The Yankees learned how to leverage the idiosynchrasies of their park, while (unsurprisingly) their visitors did not (or could not).

How do you know the Yankees didn't just get hot?

The size of the foul territory would also have an effect on walks. Smaller foul territory = more foul balls into the stands = more walks.

The size of the foul territory will also affect walk and strikeout rates. [Edit: Dammit!]

No, I understand that. But this is where every park should be the same, with maybe a minor variance based on mound differences; batter's eye, as No. 14 suggests; and umpires. That the spread is as much as it is seems to undermine the other park data.

I may be mis-understanding things, but if a park's attributes lead to a preponderance of certain baseball situations, these situations could be more or less likely to produce BB's because of baseball (not park) reasons. So, walks maybe be mostly an indirect park effect, but still a valid one.

...unrelated: has anyone ever calculated/listed foul territory areas by park? (edit: I guess not as unrelated as I thought!)

MC of A:

I'm not 100% convinced myself, think of it as more of an observation that hopefully will be explained to an acceptable degree. Also a bit of a rebuttal to the idea that the early-2009 HR rate at NYS was a fluke; it was higher than what I suspect will turn out to be the "true" HR rate at NYS, but the later-season drop *may* have been a signal, rather than noise...

I did look at the pitchers involved, and, subject to the SSS problem, the more experienced pitchers (Sabathia, Burnett, Pettitte) seemed to show improvement, while the less experienced pitchers (Chamberlain and others, IIRC) did not.

If it is indeed the case that the "big 3" starters are the locus of the improvement, then I think that would bolster the theory that it was a conscious change, one which the pitchers with better command were better able to execute.

It certainly bears watching in 2010. I doubt there is enough data from 2009 to draw a firm conclusion on this...

The size of the foul territory would also have an effect on walks. Smaller foul territory = more foul balls into the stands = more walks.

And more offense in general. Didn't Candlestick suppress offense a great deal, in large part due to the huge foul territory? It seemed like guys fouled out all the time at the 'Stick. It put a premium on fleet-footed corner infielders, which is unusual.

ESPN's data shows the New Big Bedpan in Da' Bronx as easily the #1 HR park in all of 'ball. That's what everybody was carping and kevetching about, no?

People were carping about it being an extreme HR park. Even though it was the #1 HR by this metric, that 1.27 index is not close to being historically extreme. In fact, it is much less than what old Yankee Stadium was in 2005 (1.43 Index).

Yeah, while NYS was #1 for homers, it wouldn't have been most recent years. People forget that OYS was a lefty's dream as well.

Wouldn't hitters maximizing the short RF while pitchers work away from it be essentially the NYS equivalent of Boston's use of Fenway, outhomering opponents 114-72 last year, vs 98-95 on the road?

Mall of America Field? WTF?

Park effects for walks: How does that work?

Quality of the hitters' backdrop, I assume.

I'd imagine that there's also an element of choice there, too. If you look, PetCo has a higher than average amount of walks, but lower than every other type of offense. I'd imagine that hitters at PetCo are more likely to look for a walk, since their odds of getting a hit are so much lower.

I'm not certain, but I'd imagine there's some game theory involved as well.

Mall of America Field? WTF?

Technically, that's just the name of the field and the Vikings sold it. See here. That wrong for the Twins. Most of the year it was Metrodome.

I'd imagine that there's also an element of choice there, too. If you look, PetCo has a higher than average amount of walks, but lower than every other type of offense. I'd imagine that hitters at PetCo are more likely to look for a walk, since their odds of getting a hit are so much lower.

I'm not certain, but I'd imagine there's some game theory involved as well.

And seems to me that pitchers might be a little more willing to give up a walk in a pitcher's park, knowing that several hits are unlikely to follow.

one thing i never understood: if there were no changes in the park's dimensions/boundaries that year, why would the park effect significantly change?

one thing i never understood: if there were no changes in the park's dimensions/boundaries that year, why would the park effect significantly change?

Weather and team composition.

BBs have big swings from season to season. Doesn't that rule out the backdrop?

There are a lot of weird quirks that can change things from year to year. If a key or two hitter gets injured before a long homestand, or your best starter gets a few extra home starts as opposed to road starts compared to last year. Or your opponents pitching staffs just happen to line you up with better opposing pitchers on the road versus at home. One year is just too small of a sample to eliminate all of the noise. One year park factors seem like they are pretty useless to me.

also groundkeeping differences, more/less day games, opponent differences, fluctuations in size/influence of crowd, incorporating a humidor system, distribution of umpires...

Look at Land Shark. No way the Marlins play in the 4th biggest hitters park in baseball and especially a home run haven. That's a one year fluke.

Weather and team composition.

Weather I get, but team composition should be agnostic - again, you're trying to quantify how the park affects a hitter, not how the hitter affects the park.

If a key or two hitter gets injured before a long homestand, or your best starter gets a few extra home starts as opposed to road starts compared to last year. Or your opponents pitching staffs just happen to line you up with better opposing pitchers on the road versus at home.

again, the first 2 examples should be what park factor is trying to quantify. the last, however, is a very valid point. if the mets get unlucky and face the roy halladays and adam wainwrights of the league every time they're at home, but then face 5th-starter losers every time they're on the road, it will unintentionally affect park factor.

incorporating a humidor system,

i would actually quantify that as a significant park change - like pushing back the fences =)

but yeah, i guess i see the point. in reality, despite it being 81 games, it really is small sample size, and you really have to look at multi-year park factors (again, assuming no significant park changes during those years).

but yeah, i guess i see the point. in reality, despite it being 81 games, it really is small sample size, and you really have to look at multi-year park factors (again, assuming no significant park changes during those years).

Yep. 81 games is a small sample for players, and it's also a small sample for parks.

Weather I get, but team composition should be agnostic - again, you're trying to quantify how the park affects a hitter, not how the hitter affects the park.

Original Yankee Stadium, great for LH pull hitters, death to RH pull hitters. One year, Yankees have all lefty power hitters and hit a lot more HR at home than on the road, next year they have all righty power hitters and hit more HR on the road than at home. It is an extreme example and not likely to actually happen, and it would be evened out some by the opposing teams' numbers, but you should be able to see where team composition could affect the PF, especially for individual components.

Sidenote: Chrome's spell checker is fine with "lefty" but flags "righty". Never noticed that before.

I never realized US Cellular was such a good home run park. Consistently better than this year's version of NYS.

Fewer pitches per PA yields fewer walks. More foulouts will do it. Also, at higher elevations, pitches don't break as much, resulting in higher contact rates - fewer strikeouts, fewer walks. And the hitting background.

Does anyone publish freely available park effects with L-R splits?