Every year, the debate about which division in baseball is the best crops up, and this year is no different. Most always assumes the AL East is the best; the Yankees and Red Sox are annual favorites, and the Rays have been in the mix as well. Also, the Blue Jays normally play better than people think.

But is this the case this year?

I’ve decided to look at the numbers. I took the W/Ls and Run Differential of each division to look at. I also have a column titled “Luck”; it is the difference between actual wins and pythagorean wins (aka hypathetical wins). According to Bill James, the standard deviation for Pythagorean Wins is 3 (meaning this amount should be within 3 wins of their actual wins).

The AL East is strong, as they typically are. 3 of the 5 teams have winning records, with the Blue Jays close as well. The Red Sox are projected to have a 100 win season, if they continue at their current pace.

For the run differential, only the Orioles have a negative one (by a large margin too). They are also the only team that should have a winning percentage under .500. Both Boston and the Yankees would be on pace for a 100 win season, if their record matched their runs.

The division really hasn’t been lucky. Baltimore is the only team that should have lost more games than they have. The Yankees are the tough luck team, as they are 3 wins short of where they should be.

The AL Central is the anti-AL East. 3 of the 5 teams have losing records and none of the teams are projected for 100 wins; in fact, it looks as if the Indians or the Tigers could win the division with 85 wins.

Run differential is more of the same. Only Cleveland has a positive run differential, with Chicago close to even. This shows Cleveland winning the division with 82 wins.

The division is pretty lucky. 3 of the 5 have more wins than they should. 2 teams also are above the standard deviation; the Tigers have 4 and Twins have 5 more wins than they should. The Royals are the unlucky team, with 3 wins below what they should have.

The AL West is more middle of the pack. 2 of the 4 teams are above .500. The first place Rangers are on pace to win the division with 93 wins, which is reasonable.

Much like the record, the run differential is split down the middle; the above .500 teams with positive and the below with negative. The Rangers are on pace for 94 wins if they’re runs continue at the same pace.

Overall, this is an unlucky division. It’s really just the Athletics that are unlucky; they are 4 wins below where they should be.

The NL East is much like the AL East; 3 teams at or over .500. The Phillies are on pace to break the 100 win barrier. The 2 teams below .500 are a combined 6 games under, which shows how strong the division is.

The run differential is not quite as strong though. Only 3 teams are positive, while the Nationals are close (-8 runs). Overall, the division has scored 70 runs less than their AL counterpart. The Phillies are the only team in the division that would crack 100 wins based of their pythagorean record.

The division is different on luck vs the AL East; the NL version is luckier. Only the Mets are behind on wins, and it’s only by 1. The Marlins should be 3 games below where they currently are. The Phillies will still crack 100 wins, if it continues this way.

The largest division in baseball has the lowest win percentage; this is due to having the worst 2 teams in the game (Cubs and Astros). On the current pace, the Brewers are on pace to win the division with 87 wins; 1 more than the Pirates and 3 more than the Cardinals.

The run differential is a little bit different. The Reds have the best hypathetical win percentage, although they’d only be a game up on the Cardinals. They’d win the division with 86 wins. Again, 3 teams with winning records, just switch the Reds and Brewers from actual records.

Luck is almost a wash, even though the Reds and Astros have lost 4 more games than they should of. Division leading Milwaukee has 4 more wins than they should.

Finally, the NL West is much like their AL counterpart. For record, they are both just barely under .500. The D’backs and Giants are the only teams over .500; the Giants are on pace to win the division with 93 wins, like the Rangers in the AL.

The run differential has 3 teams over .500, although Colorado and Arizona would only be 2 games up. The Giants would be winning the division again, but they would only do it with 85 wins.

This division is right in the middle on luck; the Giants have 5 more wins than they should, followed by the D’backs with 3. On the other end of the spectrum, the Padres and Rockies are the unlucky ones with 3 wins below what they should have.

Division Match Up
When comparing divisions, you have to take an average of the teams; if you went purely on stats, the NL Central (6 teams) would have the most wins (and losses) and the AL West would have the least (4 teams).

Actual win percentage goes the the NL East. The team average is 52 wins; 1 above second place AL East. The bottom is the NL Central at 46 wins per team.

Pythagorean win percentage goes to the AL East. Their teams have a run differential of +37, which would average 52 wins based off the formula; the NL East is second with +22 and 51 wins. The bottom is the AL Central, with -27; the NL Central is close at -26. Their hypathetical win percentage is essentially tied, with the NL beating the AL by .001.

Luck goes to the AL Central, who has 7 wins more than they should. The NL East (6) and NL West (1) are also lucky. The unlucky division is the AL East, with -6 wins.

(I struggled with declaring a Luck winner; do I go with the luckier team as winner, or the unlucky team? The lucky team is better than they should be, while the unlucky team are better than they show. I ended up picking luck as the winner)

I gave a weighted score to each category. Win Percentage received half the score, run differential a third, and luck a sixth.

The NL East is the clear winner.

Just for fun, I looked at the NL vs the AL.

I really can’t say I’m surprised; the AL has the rep as the better league. I attribute this to the DH; offense is better when teams can insert a pure bat into their line up. What would the Red Sox look like without David Ortiz in the line up? Or what would they look like if he played first every day? They’d have to choose between his bat, and Adrian Gonzalez‘s (not that it would be a hard choice – Gonzalez’s bat is better than Ortiz’s, plus he can play defense; I was just using this as an example). If you look at the following table, you see the AL scores more runs than they allow, while the NL is opposite (Remember, the NL is higher on both because they have 2 more teams than the AL; also, their is the 81 difference between the league because of Interleague Play):

The runs allowed for the NL is higher because of pitchers batting and pinch hitters; rarely is a pinch hitter better than a DH. And you’ll never see a pitcher that can bat better than a DH.

Check back tomorrow when I look more at divisions.