A Matter of Imbalance

Life isn’t fair, and neither is the Major League Baseball schedule. Discuss.

A Little Background

Back in the old days (not that I’m old), teams used to play the same number of games against every other team in the league. The Senators played the Yankees the same number of times they played the Tigers. They never played the Pirates or the Reds. Each team faced each other team 18 times. The competitive playing field was even, and all was right with the world.

That started to change a bit when divisional play was introduced. In 1969, each league was separated into two divisions. Teams played other teams in their division 18 times, and teams in the other division 12 times. This was different, but still fair. There were only two divisions, no wildcards, and each team in a division played against all other teams the same number of times.

In 1977, the American League added a couple of teams, and the National League followed suit much later, in 1993. The schedule changed but still remained fair, as each team played the other teams in its division 13 times, and teams in the other division 12 times.

In 1994, both leagues moved to three divisions and the wildcard spot . This confused things a bit more, but schedules were still balanced and competiton was even. But everything changed in 1997, the first year of interleague play.

Interleague games, introduced to increase the marketing appeal of the game, have created an uneven “playing field” for major league teams, and upset the competitve symmetry of baseball. You can no longer be sure that your favorite team and its hated rival will face the same level of competition over the course of a season. We can bemoan the loss of the old days (not that I’m old; I wish you’d quit bringing that up). But, for one brief article, let’s deal with it and ask what it means for our favorite teams.

This Year’s Schedule

This year, each team will play 17 to 19 games against teams in its own division and six to nine games against teams outside its division. AL West teams play nine games against each team outside its division, because there are only four teams in the division. Conversely, NL Central teams only play six games per team outside the division, because there are six teams in that division.

During interleague play, each team plays 18 games against teams in the other league, except for teams in the NL Central, which play 12 interleague games a year. Actually, all heck breaks out during interleague play. In the name of “natural rivalry,” certain teams play each other on a consistent basis, and this definitely has an impact on the pennant race. Think Yankees/Mets, Cubs/White Sox, Expos/Blue Jays, Marlins/Devil Rays, and you’ll get a sense of what I mean.

I’ve created a table of the number of times each team plays another during the year. It’s kind of hard to read, but it serves as a handy reference table. In particular, you can probably spot the difference in interleague matchups pretty easily.

Baseball forecasters analyze each team’s schedule at the beginning of the season. The problem is, they don’t really know how good each team is going to be during the season — they’ve only got last year’s record to go on. So now, with the season about 25% complete, it’s a good time to analyze the schedule again.

The Analysis

Here’s what I did. I took every team’s winning percentage from last year and the first month and a half of this year. I weighted the two records 50/50, in order to gain a decent sense of how well each team is likely to play the rest of the year — a projected winning percentage for the rest of the year.

Here are the results for the teams that have had very different records between the two years:

            2003    2004   50/50
SFG         .621    .395    .508
SEA         .562    .351    .457
KC          .512    .314    .413
MON         .512    .342    .427
ATL         .623    .472    .548
ARI         .519    .378    .448
TOR         .531    .410    .471
TBD         .389    .278    .333
LAD         .525    .611    .568
BAL         .438    .529    .484
MIL         .420    .514    .467
CIN         .426    .541    .483
TEX         .438    .595    .516
SDP         .395    .553    .474
ANA         .475    .658    .567
DET         .265    .486    .376

These estimates seem reasonable to me. I don’t expect the Dodgers to continue to play .611 ball, and I don’t expect the Expos to stay at .342. Of course, I could be totally wrong, but what the hey.

Next, I looked at each team’s schedule for the rest of the year, as measured by the projected winning percentage of its opposition for each game, and averaged the results. This approach gives a number for the rest of the season, let’s call it “schedule strength,” which we can use to evaluate the difficulty of each team’s schedule. The higher the number, the more difficult the schedule.

The Results

When reviewing the results, remember a couple of things. First, teams play a lot of games against teams in their own divisions. So teams in the better divisions will have higher schedule strength numbers. Also, good teams don’t have to play themselves, and bad teams don’t get to play themselves. In other words, the Devil Rays’ schedule strength will be higher than the Yankees‘, everything else being equal, because they can’t play themselves. Didn’t I say life isn’t fair?

Also, with about 120 games left in the season, each .01 difference in schedule strength equals about one win in the standings.

So, without further ado, here are the National League results:

National League East
ATL        0.493   0.007
FLO        0.478   0.022
MON        0.515  -0.015
NYM        0.514  -0.014
PHI        0.501  -0.001
Total      0.500

National League Central
CHC        0.511  -0.001
CIN        0.506   0.003
HOU        0.504   0.006
MIL        0.520  -0.011
PIT        0.512  -0.003
STL        0.504   0.006
Total      0.509

National League West
ARI        0.503  -0.007
COL        0.495   0.001
LAD        0.496   0.000
SDP        0.495   0.001
SFG        0.490   0.006
Total      0.496

Things look pretty even in the National League West, and there’s no appreciable difference between the likely Central competitors, the Astros and Cubs (pity the Brewers, who have played well so far). But the East is a different matter — the Marlins have more than a two game advantage over the Phillies, and four games over the poor Mets and Expos.

During the interleague period, the Fish get to play the Devil Rays twice (in the name of “natural rivalry”), while the Phillies play the Red Sox and Orioles. Also, the Marlins have already played through one of the toughest stretches on their schedule, so their current position atop the NL East is well-earned.

You can see the rhythm of the pennant race in this graph, which shows the Marlins’ 10-game running average schedule strength (that is, the 10-game running average of its opponents’ projected winning percentage). The Marlins have some easier interleague play after a tough couple of series against the Rangers and Braves in late June, and don’t play really tough opponents again until they re-enter divisional play.

When you add the Phillies to the graph, you can see how important July will be for the NL East, when the Marlins will have a clear schedule advantage over its primary competition (by the way, the Braves’ line looks similar to the Phillies’). The Marlins will want to really pull ahead at that time, while the Phillies and Braves will be in a very good position if they can at least maintain the pace.

Now for the American League:

American League East
BAL        0.507  -0.010
BOS        0.494   0.003
NYY        0.476   0.021
TBD        0.511  -0.014
TOR        0.497   0.000
Total      0.497

American League Central
CHW        0.494  -0.004
CLE        0.499  -0.009
DET        0.501  -0.010
KC         0.485   0.006
MIN        0.473   0.017
Total      0.490

American League West
ANA        0.507  -0.001
OAK        0.498   0.008
SEA        0.501   0.005
TEX        0.517  -0.012
Total      0.506

Based on schedule strength, the A’s look like a decent bet to catch up with the Rangers, who have to play six games against the Astros in the name of natural rivalry. Of course, the A’s have to play six games against the Giants, who won their division last year and could still be formidable despite their slow start. That’s why they play the games, right?

In the AL Central, the Twins have a two-game lead over their likely top rivals, the White Sox. A key reason is the difference between the Cubs and the Brewers (anyone out there think that the Twins and Brewers form a “natural rivalry”?).

And, God love ’em, those damn Yankees have a two-game lead over the Red Sox. That’s primarily the difference between the Mets and the Braves/Phillies.

I’m not making any predictions here. I’m just looking at the difference in schedules. The difference is real, and it’s important. It’s likely to have an impact on at least one divisional race. Keep it in mind when September comes around.

By the way, did anyone else notice that the toughest division, as measured by schedule strength, plays in the middle of the country? And that the worst division, measured the same way, does as well? That’s life in the great Midwest, home of the National League AND the American League Centrals.