Well, another season done, and it’s time to look back on the 2006 Blue Jays. This is a difficult squad to analyze, as they seemed to be two different teams.

First, the split between the team’s home/road records. At home the Jays were a playoff contender, compiling a sterling 50-31 mark (tied with the Yankees for second in the A.L.); away from the dome they managed only a 37-44 record. At home the Jays outscored their opponents 449/358; on the road they were outscored 360/396.

Another major discrepancy was in the team’s offence. Overall they finished in the middle of the A.L. pack, 7th in runs scored. At home, however, they were the Bay Street Bombers, scoring one run fewer than the Yankees and only 12 behind league leader Chicago. Put this bunch on the road, and they became the Humber River Hackers, finishing a paltry 11th overall. Here’s how the team breaks down, at home, in several offensive categories (road rank in parentheses):

Hits #1 (#9)

Doubles #2 (#6)

Hrs. #2 (#11)

B.A. #2 (#7)

OBP #3 (#6)

Slg % #1 (#9)

OPS #1 (#8)

Pretty darn good. Perhaps it was the raucous cheering from Section 518 that spurred them on? Then again, maybe we need to look at ESPN’s park factors to determine whether a benevolent home hitting environment was in play. According to ESPN, the Rogers Centre in 2006 had a 1.067 park factor in terms of runs scored, the second best in the A.L. behind K.C. (Go figure.) The effect of the dome on home runs was even more pronounced, increasing homers by about 27%, second only to U.S. Cellular Field at 30%.

It’s pretty clear that, in 2006, the Rogers Centre enhanced offence, more so than even such famous launch pads as Coors and Ameriquest Field in regards to homers. Any analysis of the team needs to keep this in mind. A quick perusal of the team’s individual home/road hitting splits shows a pretty wide difference. Now for many of us this is old news. The beneficial effect upon hitting that the Rogers Centre provides has been frequently noted. In my research for this little essay, I decided to compare hitting effects with the dome open versus those with the roof closed.

First, the Blue Jays played under open skies 44 times, and under the roof 37 times. This was my first shock; I had no idea the team played that many “inside” games. Was the weather that poor in Toronto? Most of the inside games were played early in the season, as one would expect (something like, all but one of the April games). I’m not sure if this differs greatly from prior seasons.

My next big eye-opener was the team’s record with the roof closed: 26-11 (.702). With the roof open the team had a 24-20 (.545) record. Simply put, close the dome and the Jays were the best team in baseball. A quick check shows the team did not seem to play weaker teams during roof-closed games; perhaps some extraneous factor like hitters being more advanced than pitchers early in the season is driving this discrepancy.

At any rate, the Jays really took advantage of the closed dome. They outscored their opponents 229/148, out homered them 60/39. As a whole, when closed, the Rogers Centre has a run park factor of 1.09 closed, and 1.05 open. With regards to homers, the closed factor is 1.32, open 1.25.

So we can conclude, for 2006, when open, the Rogers Centre is quite a good hitters park, but close the dome and those hitting advantages become magnified. Now a note of caution: further research on the closed dome factor is required (especially since the recent renovations). Generally you should look at 3 years of data before making hard and fast findings (I haven’t had time to look at the 2005/2004 numbers). Plus, I’m using the most basic park factor formulations, without any regressions, but I do think it gives us a good general picture.

Now all this information leads to several questions:

1.) If you look at the R.C. from certain angles, it looks like a pyramid. Perhaps we have some 1970s Red-Kelly-type Pyramid Power mojo happening when the dome closes, propelling the home side to inordinate heights?

2.) Given the massive positive home splits of most Jays players, just how good are some of these guys? I’ve always been the type to look at player’s road splits to get a true handle on his abilities. Is this fair? Should you penalize someone for taking positive advantage of the peculiarities of his home park? I might have to rethink this.

3.) Conversely, maybe we tend to underrate the home team’s defense and pitching abilities. In terms of preventing runs scored, the Jays were sixth overall, and in the old SkyDome were actually fifth best at preventing runs in a very difficult environment. Maybe the team should focus on getting better hitters this off-season?

4.) Given the tremendous record at home in 2006 with the dome closed, should the team leverage the park’s natural advantage of boosting home runs and build a power hitting bomb squad? Frank Thomas would look awfully good in blue. Maybe he hits 50 homers here. Perhaps the team is already aware of this… Contrast the Jays with the D-Backs, who actually play in the most homer friendly park in baseball, and are out-homered at home (the Jays actually out-homered their opponents by 27 this season at home).

5.) Now, I’m playing devil’s advocate here, given their .702 closed-dome record, but perhaps the team should close the roof for every game. Personally I believe baseball should be played outdoors, but you could make a case that in Toronto’s humid climate, sitting in 68-degree air-conditioned comfort and watching the home side dish out a whack of runs may be a good selling point.

6.) We all know “chicks dig the long ball”, but so do baseball arbitrators and agents. Building a team of sluggers has its disadvantages as such players become quite costly. Is Vernon Wells, given the huge R.C. boost that he gets, worth $15 million a year?

7.) How can the Jays become a better road team?

Less than four months until pitchers and catchers report.