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With the postseason rapidly approaching, let me offer praise to Major League Baseball. Since the introduction of the three-division format in 1994, tweaks in the first-round format improved the League Division Series (LDS), especially in terms of fairness. Awarding home field based on a rotating schedule switched to winning percentage, keeping division winners playing meaningful games longer. The two-three format gave way to the two-two-one series, ensuring the teams with the better record two home games. In this case, baseball listened to its critics, and acted accordingly.

This responsiveness has continued into 2007. MLB took advantage of the move of the World Series to a Wednesday start to make travel a bit easier in the LDS–teams get a travel day between games four and five now. Sunday night West Coast games followed by Monday night East Coast games (and vice versa) are a thing of the past. This change, however, introduced a series with three off days, meaning a team could start their one and two starters twice on a full four days of rest between starts. That could be a huge advantage, and baseball handled this very well. That series will switch leagues from year to year, and the team with the best record in that league gets to choose which schedule they want to play.

This should bring out the thinking caps for the strategists. Managers and their staffs need to weigh a number of factors in making this decision. For some teams the decision might be easy. Cleveland’s top two starters–Sabathia and Carmona–are so far superior to the rest of their rotation that avoiding the fourth starter becomes an obvious gambit. Likewise, if the Red Sox received the choice and drew the Indians in the first round, they might want to avoid giving Cleveland that advantage. If a team’s offense was nursing a number of injuries, they might want the extra day despite how the pitching match-ups might work. This choice leads to an important decision for the top team, and one more thing for fans to praise or criticize.

Adding one more such decision fills the one hole existing in the current format. This is best explained by examining the National League this season. The following table shows the run differentials of the NL playoff contenders:

NL Playoff Contenders, Run Difference, through 9/18/2007
Team Run Difference
Padres 74
Rockies 67
Phillies 57
Mets 55
Cubs 45
Dodgers 34
Brewers 18
Diamondbacks -23

The way things stand right now, the Mets, with the best record in the NL, get to play the arguably best team in the NL in terms of run difference, the Padres. However, if the Phillies end up taking the NL Wild Card, the Mets get the weaker Central Division winner. The Phillies winning the Wild Card serves the best interest of the Mets. So, given that New York built up a big lead over Philadelphia, losing two series to the Phillies might actually help the Mets in the playoffs. [Ed. note: Assuming they don’t blow it altogether and get an early start on the winter golfins.]

Let me be clear: I don’t believe the Mets didn’t play to win against the Phillies; the fact that someone might suggest as much bothers me. Recently, a reader brought up a good suggestion–allow the team with the best record in the league to choose its opponent. That team chooses between the Wild Card and the division winner with the lowest winning percentage. This would mean that the prohibition against playing a Wild Card from the same division disappears, but I don’t really see where that hurts. Yes, you might not get a Yankees-Red Sox League Championship Series (LCS), but the odds of that happening in any given season are small anyway.

The extension of the LDS’s span of time has also led to speculation MLB wants to extend that series to seven games. More games means more money, so don’t buy the excuse that a seven-game series does a better job of determining the best team. As Vegas Watch points out, the odds of the better team winning don’t go up that much.

So instead of lengthening the playoffs until games are in danger of November snowouts, why not shorten the LCS to five games? Would it really hurt the broadcasters that much? Ratings are difficult to find online, but Wikipedia does go back a few years for the World Series. The following table shows the average ratings for games one through seven of the World Series since Fox took over exclusively in 2000:

World Series Ratings by Game, 2000-2006
Game Number Number of Games Average Rating
One 7 10.5
Two 7 13.0
Three 7 12.6
Four 7 13.6
Five 5 12.2
Six 3 13.2
Seven 2 20.7

Note that the series deciding game shows a 65 percent ratings increase over the average for the previous six games (if you just look at the two series that went seven games, the increases are 66 and 63 percent). A series-deciding game adds a huge boost to the ratings. The probability of getting such a deciding contest in a seven game series is 32.8 percent. The probability of a big game when the series is best of five is 37.5 percent. So by going to a five-game format, you get a few more deciding games.

Here’s the viewership for Games Five, Six, and Seven for the two World Series that went the distance this decade:

World Series Viewers, in millions
Game 2001 2002
Five 21.1 15.8
Six 22.7 19.1
Seven 39.1 30.8

Note that in each case, a deciding game does almost as well as the previous two games combined. So making a series five games hurts in total viewership only if the series would have gone seven games. Of course, this comes at a cost. A sweep is twice as likely in a five-game series as in a seven-game series. Theory says that two evenly matched teams produce a three-game sweep 25 percent of the time, as opposed to a 12.5 percent chance of a sweep in a seven-game series. And unfortunately, the actual history is much worse than the theory:

Probability of Series Length, Best of Five
Number of Games Theory Actual (84 series)
Three .250 .380
Four .375 .310
Five .375 .310

With those kinds of numbers, you’re never going to get a series shortened to five games. In fact, these numbers represent a great reason to extend the LDS to best of seven.

Major League Baseball has tinkered effectively with the LDS over the past several seasons. They increased fairness and found ways to reward the teams that played better over the regular season. A bit more tweaking eliminates any reason for teams to prefer a particular Wild Card outcome and lose to achieve that result. While a seven-game series does little to improve the chances of the best team winning, the number of sweeps in five-game series is destined to doom those to extinction. Which means we should all get our heavy coats ready for November baseball.

Thank you for reading

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