I thought it would be interesting to take a look at surprise Super Bowl teams in recent years. I wanted to know if the surprise teams could be identified based on their prior performance. Ultimately, I thought I might be able to predict which teams might surprise us in 2007.
With the predicition model's ability to isolate the effect of luck on team wins from performance, it can calculate "expected wins" which tend to be a more accurate reflection of a team's talent and skill than their actual record.
My theory was that potential surprise teams can be identified by looking at teams with mediocre actual W-L records but had notably better expected records in the season prior to their Super Bowl appearance.
The teams I considered as recent surprise teams are listed below, along with their previous season's win totals. If I've overlooked any, I apologize.
|Team Year||Prior Wins|
I considered the '05 Seahawks as a surprise team despite their division championship the year prior because of the weakness of the division and that they won it with only 9 wins.
Going back to 1995 cost some detail in the data. Compared to my latest model, I could not use fumbles, sacks, or penalties in the regression for estimating season win totals. The model includes offensive and defensive: pass efficiency, interception rate, and run efficiency. The coefficients are derived from all 32 teams from the past five NFL regular seasons (n=160).
The result is a slight drop in model precision. R-squared drops from about 0.70 to 0.62. But for the purposes of this effort, I believe that's acceptable.
If my theory is correct, we would expect to see expected wins for the surprise teams exceed their actual wins by a notable amount. Here is the data table and the calculated expected wins.
|Team||O PASS||O INT RATE||O RUN||D PASS||D INT RATE||D RUN||Act. Wins||Exp. Wins|
We find there is no tendency for surprise teams to have higher expected wins than actual wins. The only team that shows such a pattern is the '99 Ravens who played well enough to expect 10 wins while only notching 8. We see that the '98 Rams were not quite a 4-win team, and the '96 Patriots were a little more surprising than their 6 wins in '95 indicated. Otherwise, we can't use prior expected wins to identify the Cinderella story of 2007.