Adjustments to Ground Balls for Stadium

[Waterstpub87]

Struggling with this concept.

Currently, I adjust all hits to a stadium factor.

The problem, perhaps not all pitchers are effected equally by stadiums. Say a bad ground ball pitcher in Colo would be just as bad a ground ball pitcher in San Diego, A good air ball pitcher in SF would get smashed in Toronto.

My current thought is the only Outfield Fly hits should be adjusted. This could be correct because:

1. High fences turn HRs into Outs
2. Cold weather stops the ball from carrying
3. Ground balls are unaffected by fences and weather

I could be completely wrong because:

1. Shape of fair vs. foul
2. Differences in turf

Has anyone looked into this at all or have a theoretical opinion on stadium effects on ground balls, or know where to find this information?

[KVB]

The real question is, is it going to help you? Sure, putting everything you can into a model and trying to account for everything possible has value, but are there better, more predictive stats?





In an effort to be thorough, don't go around the block to get next door.

[evo34]

Be careful. K rates are higher in pitcher's parks -- not because the strike zone is any different, but because pitchers can be more aggressive (and hitters are more desperate) in that environment. The same is true for GB/FB pitchers. You can never simulate what would have happened in a different park bc there are so many aspects of each pitch that are indirectly influenced by park.

[Waterstpub87]

Be careful. K rates are higher in pitcher's parks -- not because the strike zone is any different, but because pitchers can be more aggressive (and hitters are more desperate) in that environment. The same is true for GB/FB pitchers. You can never simulate what would have happened in a different park bc there are so many aspects of each pitch that are indirectly influenced by park.

Interesting angle. Is there anywhere that would have this data available?

[evo34]

My point is more general than the example I cited. It's that it's an extremely complex problem to measure the differential impact of certain parks on certain pitcher types. I'm sure it's doable, but the amount of work involved + the chance of a spurious conclusion make it not worth the effort/time, IMO.

[evo34]

To clarify further, when I said, "The same is true for GB/FB pitchers," I did not mean to imply anything regarding K rates; I meant that pitch type/location/quality is affected by a park before the batter ever makes contact, in addition to the more straightforward post-contact effects. Hence, a very tricky issue to dissect.

[James Marques]

What you need to calculate are balls-in-play. With that, and park data, a ball-in-play adjustment factor is pretty straight forward.

[stevenash]

Be careful. K rates are higher in pitcher's parks -- not because the strike zone is any different, but because pitchers can be more aggressive (and hitters are more desperate) in that environment. The same is true for GB/FB pitchers. You can never simulate what would have happened in a different park bc there are so many aspects of each pitch that are indirectly influenced by park.

Umpires like pitchers that throw strikes.

If you have a reputation of throwing strikes and working quickly, that pitcher will get the border line on the black called in his favor more times than not, regardless of the ball park.

Now I am not saying to ignore the ball park factor, but with the exception of Coors and a few others, ball park factors are a tad overrated.