Adjusting for Park

Vris · 07-24-2006, 10:36 PM

Hey all.

Can someone tell me how to "adjust for park" on things such as OPS+ and other stats? How do you find this single park factor to divide by? Is it a combination of the others?

Vris · 07-25-2006, 01:04 PM

Just a bump to see if anyone can help out with this.

Basic question: How do you adjust for park?

mlyons · 07-25-2006, 01:37 PM

Baseball Reference has quick-and-dirty park factors (listed under attendance/age/parks for each team). They're simple modifiers -- just divide runs or OPS or whatever by that park factor's percentage to determine what a "park-neutral" result would be (although you should make sure you're only doing it with home park results, not all of them). So a team that scores 400 runs at home in a park with a 95 factor would score (400/.95 =) 421 runs in a neutral park.

That's kind of a sloppy way to do it, though, since ballparks affect results in different ways. Dodgers Stadium, for example, is very much a pitcher's park, with an overall park factor of somewhere between 91 and 95, depending on how you calculate it. It's also an easy park to hit homeruns in, though, so a team with a lot of homerun hitters won't see their offense reduced nearly as much as a team with a lot of gap hitters (it's the most difficult park in the majors to hit a double or triple in).

I generated a bunch of park factors a few months ago. If you're really interested and feel like wading through a bunch of data, you can find them here and here.

phenom · 07-25-2006, 01:44 PM

The best way to adjust for Park is to build up your offense.

http://sports.espn.go.com/mlb/player...?playerId=3029

Vris · 07-25-2006, 01:58 PM

Thanks mlyons. That does help a great deal.

Now, how about park factors for fictional parks? How would one calculate those (in terms of OOTPland).

Parks and park factors are the one thing I have trouble grasping in SABRworld.

mlyons · 07-25-2006, 03:07 PM

The most straightforward way would be to take an "average" team in your league and calculate their runs created (using whatever method you like best -- the most basic formula is OBP * TB) and then recalculate it after rejiggering their results by OOTP's park modifiers (multiply homeruns by the homerun factor, basehits by the AVG factor, etc.). The ratio of your two results would be the overall park factor.

07-24-2006, 10:36 PM	#1
Vris Hall Of Famer Join Date: Oct 2003 Location: somewhere where I don't know where I am Posts: 3,251	Adjusting for Park Hey all. Can someone tell me how to "adjust for park" on things such as OPS+ and other stats? How do you find this single park factor to divide by? Is it a combination of the others? __________________ None Blog it.

07-25-2006, 01:04 PM	#2
Vris Hall Of Famer Join Date: Oct 2003 Location: somewhere where I don't know where I am Posts: 3,251	Just a bump to see if anyone can help out with this. Basic question: How do you adjust for park? __________________ None Blog it.

07-25-2006, 01:37 PM	#3
mlyons Hall Of Famer Join Date: Jan 2004 Location: Philadelphia Posts: 3,725	Baseball Reference has quick-and-dirty park factors (listed under attendance/age/parks for each team). They're simple modifiers -- just divide runs or OPS or whatever by that park factor's percentage to determine what a "park-neutral" result would be (although you should make sure you're only doing it with home park results, not all of them). So a team that scores 400 runs at home in a park with a 95 factor would score (400/.95 =) 421 runs in a neutral park. That's kind of a sloppy way to do it, though, since ballparks affect results in different ways. Dodgers Stadium, for example, is very much a pitcher's park, with an overall park factor of somewhere between 91 and 95, depending on how you calculate it. It's also an easy park to hit homeruns in, though, so a team with a lot of homerun hitters won't see their offense reduced nearly as much as a team with a lot of gap hitters (it's the most difficult park in the majors to hit a double or triple in). I generated a bunch of park factors a few months ago. If you're really interested and feel like wading through a bunch of data, you can find them here and here. __________________ Things can always be worse.

07-25-2006, 01:44 PM	#4
phenom Hall Of Famer Join Date: Mar 2003 Location: Near the Great Wall. On the GOOD side. Posts: 3,765	The best way to adjust for Park is to build up your offense. http://sports.espn.go.com/mlb/player...?playerId=3029 __________________ reported

07-25-2006, 01:58 PM	#5
Vris Hall Of Famer Join Date: Oct 2003 Location: somewhere where I don't know where I am Posts: 3,251	Thanks mlyons. That does help a great deal. Now, how about park factors for fictional parks? How would one calculate those (in terms of OOTPland). Parks and park factors are the one thing I have trouble grasping in SABRworld. __________________ None Blog it.

07-25-2006, 03:07 PM	#6
mlyons Hall Of Famer Join Date: Jan 2004 Location: Philadelphia Posts: 3,725	The most straightforward way would be to take an "average" team in your league and calculate their runs created (using whatever method you like best -- the most basic formula is OBP * TB) and then recalculate it after rejiggering their results by OOTP's park modifiers (multiply homeruns by the homerun factor, basehits by the AVG factor, etc.). The ratio of your two results would be the overall park factor. __________________ Things can always be worse.