The other day during a discussion about AA supposedly scouting Joe Blanton, I made a rather disingenuous remark about Blanton’s numbers compared to Romero and Cecil. MjwW correctly pointed out Blanton pitches in the NL (where last year starters had an ERA .28 lower than the AL) and mentioned park factors could also come into play. Today, during a discussion about Oswalt possibly coming to Toronto, Siggian pointed out the Rogers Centre is a hitter’s park.

This prompted my first Fanpost. How hitter friendly is the Rogers Centre?

According to Park Factors.com RC has a Park Factor of +111 explained thusly:

“This means that in the years 2008-2011, Rogers Center (sic) produced 105 runs for every 100 runs produced in the average MLB park, and 118 HRs for every 100 homers, for a mean Park Factor of 111.” and concludes “This is an extreme hitters park.”

I find their methodology odd because the numbers they use seem to be as dependent on the composition of the ballclub as the effects of the park. To further complicate matters, their not-overly-glowing description of the Rogers Centre states “When masquerading as a baseball stadium, Rogers Centre is a pitcher's park, with winds almost entirely eliminated from play when the roof is closed, which is much of the time in Toronto.”

http://www.parkfactors.com/TOR

ESPN uses a simpler formula - total runs scored by both teams when the Jays are at home divided by total runs scored by both teams when the Jays are on the road (with the amount of games equalized, though not innings).

And the results the past couple of years certainly show a hitter’s paradise - of the 30 parks, RC ranked 4th in 2011 with a factor of 1.152 and 8th in 2010 with a factor of 1.058.

But hold on a moment – in 2009 RC was 23rd with a factor of only.937, in 2008, 18th with a .959 and in 2007 21st with a .944 factor.

Then it flips again - each of the 4 years previous to that (2003-2006) RC was a top 10 hitter’s park.

http://espn.go.com/mlb/stats/parkfactor/_/year/2011

BBRef actually has 2 park factors, one for pitching and one for hitting and those numbers appear fascinatingly cyclical. Starting from the Skydome’s 1st full year of operation, it was a hitters park that became a pitchers park, then a hitters park again, then pitchers park again and is now in the hitter phase of its cycle.

http://www.baseball-reference.com/teams/TOR/attend.shtml

So what will the Rogers Centre be this year? My guess is a hitter’s park, but it could be neutral, or it could be a pitchers park. What do you think?