College football Week 2 SP+ rankings

After the first full college football slate of the season -- or at least, what constitutes "full" in 2020 -- the SP+ rankings haven't seen much movement at the top. That's to be expected when few of the top teams have played, of course.

There has been movement down below, however, and it's worth talking about. So let's look at this week's rankings.

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.

Note: the previous rank column below refers to where teams ranked in the preseason projections among only teams scheduled to play this fall at the moment. So while Alabama and UTEP were originally projected second and 128th, respectively, their previous rankings below are first and 77th because the teams above Bama and below UTEP aren't scheduled to play.