It takes a few weeks before a college football season's data begins to tell us a semi-reliable story. But with four weeks gone in the 2019 season, the SP+ ratings have begun to evaluate teams as much on in-season performance as on preseason projections. The opponent adjustments are slowly getting heavier, and teams are moving up and down in the rankings for reasons other than simply, "How did you play last week?"

Two Big Ten teams made noteworthy moves in the updated rankings, and they did it in different ways. First, Ohio State absolutely humiliated Miami (Ohio), spotting the RedHawks five points and then scoring the next 76. Against a schedule that has featured no heavyweights but minimal dead weight -- Indiana currently ranks 32nd in SP+, Cincinnati ranks 59th, and FAU ranks 76th -- the Buckeyes are winning games by an average score of 54-9. They are the only team with a top-five offensive and defensive SP+ rating at the moment, and they are up to second overall, 2.5 adjusted points per game behind Alabama and 1.8 ahead of Clemson.

Ohio State's dominance was somewhat overshadowed, however, by Wisconsin's rousing victory over Michigan. The Badgers went up 35-0 in the third quarter before allowing a couple of garbage-time scores, and despite most of the other top-10 teams looking good, too, they moved up from seventh to fifth, 0.5 points per game ahead of Oklahoma and just 0.1 behind Georgia. (Michigan, meanwhile, fell from 16th to 26th.)

With an average rating of plus-13.1 adjusted points per game, the SEC remains the best overall conference, boasting five of the top 10 teams and eight of the top 18. However, other conferences have made up ground, including both the Big Ten (plus-9.9) and the rapidly rising Big 12, which began the season with a plus-6.9 average but has risen to plus-12.1. The conference has risen because of its middle class -- Oklahoma is the only top-15 team, but seven teams rank between 19th and 33rd.

Note: 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.