If you were looking at two college football defenses and trying to determine, just from statistics, which one is “better,” what would you look at? Well, first you would have to define what you meant by “better.” Better could mean “performed better in the games that have been played,” or better can mean “more likely to outperform the other team in the future.”

To judge the former is notionally simple. The better defense gave up the fewest points. If you want to mess around on the fringes, you can try to adjust for some context. Easier: Touchdowns given up by special teams or the offense shouldn’t count against the defense. Harder: Adjusting for context, such as schedule strength or offensive environment. But, in the end, points allowed describes very well what actually occurred.

But here’s the thing, if you want to judge which defense is going to be better in the future, points given up are less predictive of future defensive performance than some other component defensive statistics. When looking at statistics, I prefer to use rate statistics (yard per carry, yards per attempt) as opposed to gross statistics. Rate statistics automatically adjust for different paces of play. Mizzou’s style of offensive play over the last four years has resulted in the defense facing 5 – 10 more plays than the average defense over the course of a game. So, if our defense and an average team’s played identically, Mizzou would give up 50+ more yards a game solely due to offensive context. I think yards per rush, yards per passing attempt, turnover margin, TD% in red zone, and third down conversion % are the best statistics to look at to get a sense of how well a defense is performing on the matters within its control

With that in mind, consider the following three teams’ performances in these key defensive statistics thus far in 2008:

Team A is the Texas Longhorns; Team B is the Missouri Tigers. Team C is….the Missouri Tigers if you remove the three games the Big 12 has played against ranked opponents (MU v. IL; KU v. USF and Baylor v. Wake Forest).

Interestingly, the media and public perceptions are that Texas has a much improved defense while Mizzou’s defense has been a titanic disappointment. The stats largely don’t bear this out. The two defenses (even including the MU v. IL game) are very similar. The only difference is that Texas has done a better job of keeping opponents out of the end zone…which, of course, is a pretty big damn difference. What is done is done and Texas deserves kudos for keeping its noncon opponents out of the endzone. But the real question is….which of these two defenses can be expected to perform better going forward?

Two things jump out. First, the difference between Mizzou’s and Texas’ defensive performance is largely contextual. Mizzou played a legitimately good Illinois team while Texas has played nobody. If you remove the Illinois game, Mizzou and Texas have played a comparable schedule. According to CFN, Texas has played the number 97, 113 and 99 teams while Mizzou has played the number 84, 94 and a bad FCS team. And with the Illinois game gone, Mizzou’s and Texas’ defenses are virtually indistinguishable in every major category (note that I am ignoring yards per game…Missouri’s defense has faced an average of 9 more plays per game than Texas’ has, this is almost completely due to Missouri’s offense being so fast paced). Most notably, Mizzou’s yards per pass attempt go way down to a very good 5 and every other important statistic is a virtual dead heat.

Second, even with the Illinois game included, Texas’s scoring defense is seriously outperforming its component statistics, while Mizzou’s is underperforming its component statistics. In particular, Texas is giving up an absurdly low percentage of touchdowns on its opponent’s trips into the red zone, at 27%. For perspective, Iowa and TCU were the only two teams in the country last year under 40%. Further, Texas’s defense is doing a poor job taking the ball away. Missouri’s defensive statistics are middle of the pack in the Big 12, except for rush defense, which is stellar. Based on these statistics, I would expect Missouri’s scoring defense to be middle of the pack in the Big 12, which is very good considering the number of plays they face.

In short, solely looking at the statistics and the context in which they arose, I would expect the Texas and Missouri defenses to be roughly equal going forward. The only difference between the two now is that Juice Williams hit a few long passes.

The shrieks from the Chicken Little Missouri fans about the defense need to stop. Yes, there were some alarming plays against Illinois. No, none really threatened to lose the game, and when the defense needed to come up big, it did so. Since, the defense has been very good, limiting its opponents to 5 yards per attempt in passes and under 2.5 yards per carry on runs.

Next up, a more in depth look at Mizzou’s defensive performance through its noncon slate.