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Stats Relevance Watch, Part One

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Wherein SMQ examines the final regular season statistics in more than a dozen  major categories to suss out who succeeded in what and how that statistical success correlated to overall success in terms of final record. I don't not have the luxury of a high-powered supercomputer or degree-type qualification in mathematics or statistics, but analysis here will be driven as deep as my egghead, tinfoil cap curiosity and cell phone calculator will take it. That is to say, quasi-scientific at best. If you've ever said "the only number that matters is the one on the scoreboard" or anything to such effect, click here and don't be such a philistine.
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Part One: Which stat correlates most closely to success?

There are many ways to define "success;" for simplication, I'm stating simply: level of success=record. This is not strictly true, of course, as an 8-4 team from the Big Ten, because of the higher level of competition it must overcome to achieve that record, has likely had more success than a 9-3 Sun Belt team, if such a thing existed. But such distinctions are too fine for our purposes - we are making generalizations at this stage. We'll get a little more specific in later editions.

The method: From the NCAA's rankings in 16 major statistical categories (rush offense, pass offense, pass efficiency offense, total offense, rush defense, pass defense, pass efficiency defense, total defense, turnover margin, third down offense, third down defense, time of possession, penalty yards and, just for fun, yards per punt return, yards per kickoff return and net punting), pull out the top 20 teams and bottom 20 teams in each category for the 2007 season. Combine the records of those teams into a winning percentage for the best and worst of each category. Rank categories by number of wins of the top 20 and the bottom 20, as well as the margin between the two; the "most important" category, it would follow, would be the one with the best records at the top, the worst records at the bottom and, therefore, the greatest disparity between.

Note please the term "correlate," which of course is not "cause." There are a number of reasons for the records in each category to look the way they do, and numerous possible cause-effect relationships to be drawn (i.e., teams that trail often have to throw to catch up, and throwing therefore is inherently tied to bad teams; vice versa in the case of rushing). So the fact that, for instance, the collective records of the best passing offenses do not match those of the best rushing defenses is not an argument against ever throwing the ball.

Win % of Top 20 Win % of Bottom 20 +/-
Rush Defense .750 (198-66) .313 (76-167) + .437
Pass Eff. Defense .719 (187-73) .301 (74-172) + .418
Total Defense .720 (188-73) .312 (77-170) + .408
3rd Down Offense .696 (183-80) .329 (80-163) + .367
Turnover Margin .681 (177-83) .320 (82-174) + .361
Pass Eff. Offense .705 (184-77) .350 (86-160) + .355
Total Offense .680 (176-83) .357 (87-157) + .323
3rd Down Defense .697 (182-79) .395 (100-153) + .302
Pass Defense .626 (159-95) .402 (101-150) + .224
Time of Possession .612 (156-99) .399 (99-149) + .213
Rush Offense .589 (152-106) .396 (95-150) + .193
Yards/Kick Return .632 (163-95) .462 (116-135) + .170
Pass Offense .602 (154-102) .476 (119-131) + .126
Yards/Punt Return .496 (124-126) .486 (122-129) + .010
Penalty Yards .532 (134-118) .544 (134-114) – .012
Net Punting .548 (138-114) .583 (148-106) – .035

Altogether now...

Clap clap clapclapclap


De-fense!
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Again, the most important thing to take away is that virtually every category - certainly every category typically presented as meaningful - correlated to winning on the top end and losing on the bottom; success in all of these areas generally reflected success overall. Past that generalization, the best teams in the three major non-scoring defensive categories not only won more than teams excelling in any other category, but the worst defensive teams lost more, too. Among the top 20 teams, this is exactly the same result as last year and in the much smaller look the year before that.

Offensively, we see that the best teams were far more efficient that they were necessarily explosive: turnover margin, passing efficiency and third down percentage correlated to better records at the top and worse records at the bottom than even total offense, and to much better/worse results at the poles than rushing or passing yards per game; even an essentially ancillary number like time of possession showed a greater correlation to success than yardage in either category (later editions in the series will feature more yards per carry/pass numbers, which last year's results lead me to hypothesize a reversal on that front).

In relation to last year's rankings by category (special teams categories not included - see below):

2006 2007
Rush Defense 4 1
Pass Eff. Defense 3 2
3rd Down Offense 1 4
Total Defense 5 3
Pass Eff. Offense 3 6
Total Offense 2 7
Turnover Margin 9 5
3rd Down Defense 6 8
Pass Defense - 9
Rush Offense 7 11
Time of Possession 12 10
Pass Offense 11 12
Penalty Yards 13 13

The numbers aren't identical, but we do see the same trend: the best defensive teams had the best results, followed by the most efficient offensive teams.

For returning readers familiar with last year's debate over the stunning irrelevance of penalty yardage, we have an even less meaningful indicator: net punting, which - like penalty yards - had a slight, essentially meaningless yet existent correlation to losing. One potential response: these events (along with return yardage and other special teams indicators, though kick return average had a better correlation to success than average passing yardage) just don't happen very often, i.e. a small sample size results in a high degree of variability. If teams punted or returned kicks 75 times per game instead of, like, four or five, then a) that would be a very different, boring game, like soccer or something, and b) great punters and return men would have a much greater impact on outcomes. As it is, except in two or three obvious, game-winning-fiedl-goal type situations per season, the kicking game is something you just don't want to completely screw up.

Of course, in this version the best (and worst) teams in any given categories are often the same teams; balanced winners like LSU, Ohio State and Southern Cal, for example, are represented over and over again on the top, just as Florida International and Minnesota are at the bottom. In part two, we'll flip the game, from looking at the stats as defined by the teams to looking at the teams as defined by the stats: what, exactly, do the best teams do the best?