130-team S&P+ rankings, where we once again have a new No. 5 team

Below are this week’s new S&P+ rankings.

A reminder: S&P+ is intended to be predictive and forward looking.

Good predictive ratings are not résumé ratings, and they don’t give you bonus points for wins and losses. They simply compare expected output to actual output and adjust accordingly. That’s how a given team can win but plummet or lose and move up.

Through six weeks, the S&P+ rankings are performing quite well, hitting 56 percent both against the spread and on the over/under point totals for the year.

As you would hope, the absolute error — the average size of miss between projection and reality — has settled into a healthy area as well.

If you’re interested in a decent résumé ranking of sorts, I encourage you to visit this post on strength of schedule. I created a Resume S&P+ ranking and will be updating it on Mondays throughout the rest of the season.

Below, however, are the predictive ratings, the actual S&P+.

(You can find full unit rankings, plus a yearly archive, at Football Outsiders. The offense and defense pages will start getting updated in the coming weeks.)

A quick reminder:

As non-conference play ends and conference play begins, the scoring margins tend to get closer on average. As a result, the overall spread of S&P+ ratings — which is distributed along the bell curve for scoring margins — tends to get smaller, too.

You’ll notice that Alabama’s S&P+ rating fell from plus-30.3 adjusted points per game to plus-29.6 despite obliterating Arkansas on Saturday. That “fall” is a product of the scoring adjustment, not anything the Tide did on the field. Their percentile rating improved from 99.2 percent to 99.3 this week.

Because of this, you’ll also notice that all the top conferences’ average ratings fell, while all the bottom conferences rose. Same concept there.

Okay, now that that’s out of the way ...

Your New/Old No. 5 Team of the Week: Michigan

It’s been painfully clear who the top four teams in the country — or at least, the four teams with the most proven upside — have been, and it’s basically who we expected: in some order, Alabama, Ohio State, Georgia, and Clemson. Alabama has been No. 1 since Week 2, and the other three continue to shuffle amongst themselves. Notre Dame has been playing like an elite team of late, but the Irish are still statistically paying for their early-season struggles.

The most drama in the rankings, then, has come just below the top four.

The top team not named Bama/OSU/UGA/Clemson has shifted:

• Washington began No. 4 but fell after losing to Auburn.
• Oklahoma jumped to second before settling back in near its No. 8 preseason ranking.
• Boise State’s early dominance produced a surge to No. 5, and the Broncos immediately crashed and burned at Oklahoma State.
• Mississippi State took the No. 5 spot from BSU and immediately got smoked at Kentucky.
• Michigan took over, damn near lost to Northwestern, and fell two spots. A blessing, really.
• Washington moved back into the top five in week five, then gave serious consideration to losing to winless UCLA and fell to 10th.

The Curse of No. 5 nearly befell the Huskies, but now they’re out of the five-hole, and this week’s new “top teams not named Bama/OSU/UGA/Clemson” is another old name: Michigan.

Like Washington, Michigan has just been waiting around for another shot at a big win. The Wolverines lost to Notre Dame in South Bend to start the season and have won their five games since by an average of 28 points, and that’s with the close call at Northwestern. Their reward for moving back into the top five: a visit from No. 13 Wisconsin. If the Curse of No. 5 is real, you know which way to bet on that one.

The week’s top movers (good)

1. New Mexico (up 27 spots, from 105th to 78th)
2. Georgia Southern (up 18 spots, from 83rd to 65th)
3. Miami (Ohio) (up 16 spots, from 95th to 79th)
4. Air Force (up 16 spots, from 117th to 101st)
5. Utah State (up 15 spots, from 40th to 25th)
6. Houston (up 12 spots, from 41st to 29th)
7. Cincinnati (up 12 spots, from 52nd to 40th)
8. Pitt (up 12 spots, from 85th to 73rd)
9. NIU (up 12 spots, from 96th to 84th)
10. Middle Tennessee (up 12 spots, from 108th to 96th)

It was a good week for run-heavy teams, I guess. New Mexico completely destroyed a UNLV team playing its backup QB, Georgia Southern followed up on its upset of Arkansas State with a romp over South Alabama, Miami (Ohio) destroyed Akron (Miami’s more of a conservative team than a run-heavy one, but go with it), and Air Force rolled Navy (another run-heavy team, granted).

The most interesting team on this list, however, might be Utah State. S&P+ already liked the Aggies enough to project them to win by eight points as an underdog at BYU. Instead, they won by 25. All four wins have come by double digits, their only loss is a narrow one at Michigan State, and they are out-gaining opponents by 1.9 yards per play.

UCF is obviously in the front of the line for the Group of Five’s NY6 bowl bid, but if the Knights slip, you could say that Appalachian State and USU now have the strongest cases as top understudies.

Top movers (bad)

1. North Texas (down 18 spots, from 32nd to 50th)
2. Navy (down 18 spots, from 77th to 95th)
3. South Carolina (down 17 spots, from 29th to 46th)
4. Wake Forest (down 17 spots, from 72nd to 89th)
5. UNLV (down 13 spots, from 94th to 107th)
6. Virginia Tech (down 12 spots, from 35th to 47th)
7. Maryland (down 12 spots, from 56th to 68th)
8. Vanderbilt (down 11 spots, from 64th to 75th)
9. 5 teams down 10 spots

North Texas’ stock has fallen considerably following a loss to Louisiana Tech and a narrow escape against a bad UTEP (the Miners did move out of the bottom spot in S&P+ this week!), but I’m guessing one team in particular is going to catch the eye here, and not only because I put it in bold face.

That’s right, South Carolina just did a very Will Muschamp thing, beating a top-30 team in Missouri ... and falling 17 spots. How?

First, remember that teams are pretty bunched together here. The difference between No. 29 and No. 46 is only about 3.9 adjusted points per game, or basically the difference between No. 1 Alabama and No. 2 Clemson. That said ...

Games aren’t played on paper, which is a good thing for the Gamecocks because on paper, they lost on Saturday. They beat Missouri 37-35 despite the following stats:

• Total yards: Mizzou 490, South Carolina 377
• Yards per play: Mizzou 6.0, South Carolina 4.6
• Success rate: Mizzou 43.9%, South Carolina 30.5%
• Scoring opportunities: Mizzou 9, South Carolina 7
• Field position: Mizzou 33.7, South Carolina 33.5

My post-game win expectancy measure — in which all the key stats (the ones that almost always decide games) are tossed into the air and produce a “You could have expected to win this game X percent of the time” number — gave South Carolina a four percent chance of winning. Average scoring margin for a game like this: Mizzou by 17. But this thing got really, really strange when a storm blew through Columbia, S.C., and the Gamecocks navigated the rain well enough to break math.

Being that S&P+ is a predictive measure, however, it looks at a game like this and says, “Yeah, that was a fluke,” and adjusts accordingly. The Gamecocks were without their starting quarterback, Jake Bentley, so you could say this is too drastic a course correction. But S&P+ isn’t designed to take injuries into account, and Mizzou was without two-thirds of its starting receivers and, at times, one to two starting offensive linemen, too, so it’s probably not too drastic.

This is not the first time a Will Muschamp team has broken math, by the way. Hell, it’s not the first time he’s broken math against Missouri.

Another unlikely result from this week: Texas over Oklahoma. The Horns had a 9 percent post-game win expectancy against the Sooners, getting out-gained by 2.5 yards per play and allowing a 61 percent success rate. But that one’s at least easier to understand: turnovers, turnovers, turnovers.

Texas had a plus-3 turnover margin when stats suggest about a plus-1.4 margin was more likely. Turnovers are worth about five points in field position lost and gained, so you could say the god of randomness gifted the Horns about eight points in a three-point win.

FBS conferences, ranked by average S&P+ rating:

1. SEC (plus-11.7 adjusted points per game, down 1.0 points)
2. Big 12 (plus-7.2, down 0.2)
3. Big Ten (plus-6.9, down 0.7)
4. Pac-12 (plus-4.8, down 0.6)
5. ACC (plus-4.6, down 0.6)
6. AAC (minus-0.2, down 0.1)
7. Mountain West (minus-2.4, up 1.3)
8. Sun Belt (minus-6.8, up 0.7)
9. MAC (minus-8.2, up 0.7)
10. Conference USA (minus-8.2, up 0.5)

Again, the scoring curve is the primary reason for the top conferences falling and the bottom conferences rising, but there was still movement within this movement. The Big 12: now your second-best conference in FBS.

---

Another reminder: I have made a few philosophical changes in this year’s S&P+ rankings.

When I get the chance (so, maybe in the offseason), I will update previous years of S&P+ rankings to reflect these formula changes, too.

1. I changed the garbage time definition. S&P+ stops counting the major stats once the game has entered garbage time. Previously, that was when a game ceased to be within 27 points in the first quarter, 24 in the second, 21 in the third, and 16 in the fourth. Now I have expanded it: garbage time adjustments don’t begin until a game is outside of 43 points in the first quarter, 37 in the second, 27 in the third, and 21 in the fourth. That change came because of a piece I wrote about game states at Football Study Hall.
2. Preseason projections will remain in the formulas all season. Fans hate this — it’s the biggest complaint I’ve heard regarding ESPN’s FPI formulas. Instinctively, I hate it, too. But here’s the thing: it makes projections more accurate. Our sample size for determining quality in a given season is tiny, and incorporating projection factors found in the preseason rankings decreases the overall error in projections. So I’m doing it.
3. To counteract this conservative change, I’m also making S&P+ more reactive to results, especially early in the season. If I’m admitting that S&P+ needs previous-year performances to make it better, I’m also going to admit that S&P+ doesn’t know everything it needs to early in a season, and it’s going to react a bit more to actual results.

Basically, I’ve added a step to the the rankings process: after the rankings are determined, I go back and project previous games based on those ratings, and I adjust the ratings based on how much the ratings fit (or don’t fit) those results.

The adjustment isn’t enormous, and it will diminish as the season unfolds.

Testing this process for past seasons improved performance against the spread a little and, more importantly, decreased absolute error (the difference between projections and reality) quite a bit. I wouldn’t have made the move if it didn’t appear to improve performance.