Projecting a Realigned MLB

On Monday, nestled in his comments on potential radical changes, Rob Neyer called for some simulation work, saying the following:

“When thinking about the impact of realignment, additional wild cards, or whatever, it would be shockingly simple to set up some simulations and figure out what it would mean for competitive balance, fairness, fan interest, TV ratings, attendance, etc.”

With the help of a season simulation that decides the outcome of each game using the log5 formula, we can address the impact different realignment options would have on the 2010 season. I will measure the impact by comparing playoff probabilities across the various alignments. The alignments simulated were the current divisional alignment, an alignment based on 2009 record and an alignment based on 2009 payroll. The divisions in the realignment options were created using a snake system based on each criterium, and the fallout is as follows.

MLB, Realigned By 2009 Record

NL 1	NL 2	NL 3	AL 1	AL 2	AL 3
Dodgers	Phillies	Rockies	Yankees	Angels	Red Sox
Marlins	Giants	Cardinals	Tigers	Twins	Rangers
Braves	Cubs	Brewers	Mariners	Rays	White Sox
Astros	Padres	Reds	Indians	A’s	Blue Jays
Mets	Diamondbacks	Pirates	Royals	Orioles
		Nationals

MLB, Realigned By 2009 Payroll

NL 1	NL 2	NL 3	AL 1	AL 2	AL 3
Mets	Cubs	Phillies	Yankees	Tigers	Red Sox
Braves	Astros	Dodgers	White Sox	Mariners	Angels
Cardinals	Giants	Brewers	Indians	Blue Jays	Orioles
Reds	Diamondbacks	Rockies	Twins	Royals	Rangers
Nationals	Pirates	Padres	Rays	As
		Marlins

I used CHONE projections (specifically the Starting Lineup Projected Standings) for the team’s strengths and simulated each season 10,000 times. The resulting playoff probabilities are as follows:

Projections Of Realigned MLB

NL	Current	2009 Record	2009 Payroll
Cardinals	74%	70%	64%
Braves	62%	63%	55%
Rockies	40%	33%	31%
Dodgers	39%	37%	35%
Phillies	38%	53%	40%
Diamondbacks	27%	29%	45%
Cubs	21%	21%	35%
Brewers	21%	20%	16%
Mets	16%	16%	16%
Marlins	13%	13%	12%
Reds	13%	11%	8%
Padres	12%	12%	8%
Nationals	8%	8%	6%
Giants	8%	8%	13%
Pirates	4%	3%	8%
Astros	4%	3%	8%
AL	Current	2009 Record	2009 Payroll
Yankees	83%	93%	86%
Red Sox	64%	84%	80%
Twins	47%	35%	21%
Rangers	45%	34%	25%
Rays	33%	53%	41%
Angels	33%	28%	20%
Indians	27%	18%	10%
White Sox	22%	14%	7%
A’s	17%	14%	37%
Mariners	13%	10%	31%
Tigers	7%	4%	14%
Royals	5%	3%	13%
Orioles	3%	8%	6%
Blue Jays	1%	2%	9%

A few observations:

The big takeaway is this: The Red Sox benefit from being in a non-Yankees division, becoming nearly as close to a playoff lock as the Yankees themselves. And New York even sees its playoff odds increase in both realignments. The bottom line is that splitting up these two teams just makes it more likely that both of them make the playoffs.

In the NL, there are only a few instances where playoff probabilities change drastically. One is the Phillies becoming the top projected team in their division under the 2009 record alignment. The other is because of the relative weakness of Division 2 in the 2009 payroll alignment, allowing some weaker-projected teams to make the playoffs more often.

In the AL, most of the large swings in playoff probabilities result from moving into or out of divisions that have either the Yankees or Red Sox.

The Rays, one of the teams most often seen as the biggest victim of the current alignment, pass the Twins and Rangers to become the third-most-likely team to make the playoffs in either realignment.