There have been a number of studies the last few years of what succeeds in the playoffs and in the Super Bowl. Put together, the arguments are quite compelling, and for the most part boil down to "defense wins championships," being more than just a cute saying. When one considers the history of playoffs and the Super Bowl, it becomes clear that the Bears are the team to pick on Sunday. This begs the question of why the Colts are being picked by all the experts, including the professionals. I think i know why, and i also think the arguments for why the Colts will win are either invalid or misguided. This diary explores why history favors the Bears, and why the arguments for the Colts don't hold much water.

First, lets look at Super Bowl and playoff history, which heavily favors defensive teams, and thus the Bears. John Dewan from baseball info solutions posts a stat of the week. This week, he discusses two trends that heavily favor the Bears. First, there have been 11 Super Bowls where one team's defense has surrendered at least 50 points fewer than their opponent's defense over the course of the season. The defenses that are at least 50 points better are 11-0. This year, the Bears defense has surrendered 105 points less than the Colts D over the course of the year. Clearly, this trend strongly points towards a Bears win. Last week's "Stat of the Week," showed a set of 12 statistics each of which independently predict the Super Bowl correctly at least 55% of the time. The prediction utility of these numbers increases when taken together. The team that wins more of these statistics has won 14 of the last 16 super bowls. This year, the Bears are better than the Colts in 9 of the 12 statistics, and the two teams were tied in one. That means the Colts only won 2 of the 12 stats: the 10th and 12th best predictive stats of the 12 used in the system. Team's favored in 9 or more of the 12 categories at 15-3 in the Super Bowl, another trend heavily favoring the Bears. If one actually looks at the statistics in the system, a clear trend emerges: most of them are associated with measurements of a team's defense and its ability to control the clock. Given that, its no surprise the Bears are favored by this system. Similarly, consider the study done by Football Outsiders at the outset of this year's playoffs on what wins in the playoffs. Its an excellent article, which i would recommend to anyone that has the time to read it. If you don't here's a quote from the article summarizing the impact different units have on a team's playoff success:

• A good defense is important, specifically a good run defense
  
• A good offense doesn't mean very much
  
• A kicker's regular season performance means nothing for the playoffs
  
• A team's end-of-season momentum isn't as important as it might seem

One other trend that is important but not mentioned in that synopsis: the quality of special teams is a better predictor of postseason success than the quality of offense is.

I can't imagine a better set of trends arguing for the Bears winning this game. The Bears strengths are their defense, special teams, and its aggregate performance over the course of the season. The Colts strengths are its offense, clutch kicker, and late-season resurgence. The Bears' strengths are emphasized in the payoffs, whereas the Colts strengths are not as important. Finally, consider a statistic posted by "Tampa Bay Mike" in an open discussion on Football Outsiders: top 3 defenses are 9-0 in the Super Bowl against top 3 offenses. Once again, the old adage is backed up by objective historical analysis: defense wins championships.

OK, given all this, why is everyone picking the Colts? The main argument is that the Bears D isn't as strong as it once was, whereas the Colts D is all the sudden a juggernaut, largely because of the return of Bob Sanders to the Colts and the loss of Tommie Harris to the Bears. While the Colts have improved since the return of Sanders, the principle that a team can be greatly affected by injury is not considered to its fullest extent. To realize the problem here, consider when Tommie Harris was first injured: during the Minnesota game in week 13, the week after the Bears clinched a playoff spot. The remainder of the Bears regular season was spent resting defensive backs Charles Tillman, Nathan Vasher, and Todd Johnston. Those guys were all healthy in the post season (although Johnston wasn't 100% in the Seattle game). To realize the importance of their absence during the Bears late season swoon, we can look at what the Bears D was worse at during their absence. Again, the Football Outsiders crew is quite useful in aiding our analysis. In their Super Bowl prediction, they state (emphasis mine):

The good news for Bears fans is that the Chicago defense finally reverted to form in the NFC Championship victory against New Orleans. According to single-game DVOA, it was Chicago's best game since the Harris injury. It was the first game since the Harris injury where the Bears played above-average pass defense, and the first game where they had more than two takeaways.
If you look at the numbers posted in that article, you'll see the Bears D was still above average against the run in weeks 13-17, but went from a dominating pass defense to below-average over that time. Later on, the article shows the yards per pass attempt went back down against the Saints. The bottom line here is that although the defense isn't as strong as it was with Tommie Harris, is also isn't as weak as it was when Todd Johnston, Charles Tillman, and Nathan Vasher were taking turns resting injuries.

There's a second problem with the media's sudden obsession with the Colts D, demonstrated by the Football Outsiders Super Bowl prediction. In that article, they show that the Colts D has become worse the last few weeks at defending deep balls over the middle (hello, Berrian!), is still not good against runs off left tackle, and may be further weakened by a high ankle sprain injury to one of their starting cornerbacks, Nick Harper - an injury that usually takes 3-4 weeks to heal. I've done my own analysis trying to find out what causes Rex Grossman to succeed or fail, and he tends to do much worse than a normal QB against good pass defenses but much better than a normal QB against bad pass defenses. The Colts pass D is susceptible to the bomb even with Nick Harper AND Bob Sanders in the lineup. Without one (or both), Grossman should be able to hit Berrian deep at least once. Furthermore, as Chad pointed out in a diary earlier this week, the Colts don't blitz much, and John Morgan's analysis of the Colts D will tell you that, contrary to popular perception, they are bad at rushing the passer. And even when the Colts get pressure, it almost always comes from the edges, whereas Grossman's biggest problems seem to come from a strong pass rush up the middle. Finally, Grossman claims his mishaps come primarily from a lack of focus, and i'm fairly certain he'll be properly focused for Sunday's game. Put all of this together, and things look dire for Indy's pass D, particularly if Nick Harper can't play.

There are a whole bunch of other numbers that heavily favor the Bears, such as the Colts 5-4 record on the road versus the Bears 7-1 road record, the 60% chance of rain on Sunday night, and how most of the Bears strengths are up against Colts weaknesses, and the opposite is true for Colts strengths. But the main reason the Bears will win is quite simple...

DEFENSE WINS CHAMPIONSHIPS!!!