This might be the time of year in which computer ratings and the résumé ratings we have in our heads disagree the most. Top teams get upset, but the computer doesn't dump them as much as we expect. Unbeaten teams don't automatically move way up just for not losing.
With that in mind, let's go ahead and start with the disclaimer:
What is SP+? In a single sentence, it's a tempo- and opponent-adjusted measure of college football efficiency. I created the system at Football Outsiders in 2008, and as my experience with both college football and its stats has grown, I have made quite a few tweaks to the system. SP+ is intended to be predictive and forward-facing. That is important to remember. It is not a résumé ranking that gives credit for big wins or particularly brave scheduling -- no good predictive system is. It is simply a measure of the most sustainable and predictable aspects of football. If you're lucky or unimpressive in a win, your rating will probably fall. If you're strong and unlucky in a loss, it will probably rise.
Like most predictive systems, SP+ is designed not to overreact. Oklahoma fell after losing to Kansas State in Week 9, but only from third to fourth. Wisconsin has fallen after losing to Illinois and Ohio State, but only from fourth to eighth. Missouri has been penalized severely for utterly collapsing over the last two weeks but has only fallen from 10th to 22nd.
Similarly, teams that have shifted into fifth gear in recent weeks, haven't risen as much as they might end up rising -- Clemson has moved from eighth to fifth in two weeks, and Minnesota has gone from 26th to 12th in three weeks.
So just as college football itself is undergoing some repositioning after three top-five teams in three weeks lost as huge favorites, SP+ is in transition mode, too. One thing is not changing, though: Ohio State and Alabama are the top two teams. With ratings of 35.3 and 34.1 adjusted points per game, respectively (which means they are considered about five touchdowns better than the average FBS team), the Buckeyes and Crimson Tide have been the class of college football. And Bama's got No. 3 LSU coming up awfully soon. Can't wait.