Re: [Phys-l] TV technology, the World Series and physics

["Robert Cohen" <Robert.Cohen@po-box.esu.edu>]

Anthony Lapinski wrote:
> Still, other things being equal, it IS easier to hit a home run out of

> a smaller park!

To which Bill Nettles responded:
> This is merely one hypothesis, plus you have to define "easier". The
data does not support this.

I have kept out of this discussion because I didn't see it being related
to physics.  However, when I see a potential error in data analysis, I
feel compelled to write something.

In particular, I think it can be dangerous to use a single data point to
refute or confirm a hypothesis.  In this case, I assume Bill Nettles is
referring to the data provided by ESPN (via Daryl Taylor), which
indicated that Citizen's Bank park is 19th out of 30 teams in home run
production.  

Just because Citizen's Bank Park is 19th out of 30 in home run
production does not necessarily refute AL's contention that it is easier
to hit home runs out of a smaller park.

As others have pointed out, maybe the Phillies just didn't hit many
homeruns this year.

To test this hypothesis, I went to the MLB site and found that the
Phillies were 18th in home run production this year.

Hmmm...maybe the lower home run rate is because the Phillies as a team
didn't hit a lot of home runs.

There is reason to believe that the home run rate at a stadium is
intimately tied to the home run prowess of the athletes on the home
team, so perhaps a better measure is the # of homeruns hit at home (by
both teams) divided by the # of homeruns hit away (by both teams), a
stat also available at ESPN:

http://espn.go.com/mlb/stats/parkfactor/_/sort/HRFactor

In 2011, Citizen's Bank Park is 16th out of 30.

Still, just one data point.  I decided to check Citizen's Bank Park and
Petco Park (San Diego; known as a "pitcher's park" - I don't know the
actual dimensions of either park).

Here is what I found:

2011: Citizen's Bank Park 16th, Petco 23rd.
2010: Citizen's Bank Park is 10th, Petco 22nd.
2009: Citizen's Bank Park is 16th, Petco 29th.
2008: Citizen's Bank Park is 11th, Petco 30th.
2007: Citizen's Bank Park is 1st, Petco 29th.
2006: Citizen's Bank Park is 6th, Petco 15th.
2005: Citizen's Bank Park is 3rd, Petco 30th.

It seems pretty consistent that a "hitters" park routinely allows more
home runs than a "pitchers" park, consistent with Anthony's hypothesis.

I don't know why Citizen's Bank Park isn't higher on the list.  However,
as I wrote earlier, I don't know the dimensions of Citizen's Bank Park.
Given the ranking in 2005-2007, maybe the park underwent a modification
to increase the dimensions and/or other parks have been built since 2007
and those new parks are smaller. I don't know, but at least the data
can't be used to refute AL's hypothesis.

Robert A. Cohen, Department of Physics, East Stroudsburg University 
570.422.3428   rcohen@esu.edu    http://www.esu.edu/~bbq