The past couple of weeks, I was using a quasi-Elo style rating system to produce college football team ratings. And while after five weeks it is still far too early to put much faith in any computer ratings, we can at least begin framing the discussion of which are the most impressive teams in college football. So, as we did last year, the first edition of the college football SRS ratings are coming out at the end of September. As a reminder, here is the methodology:
1) For each game not played at a neutral site, 3 points are given to the road team. After that adjustment, all wins and losses of between 7 and 24 points are recorded exactly as such. This means that a 24-10 road win goes down as +17 for the road team, -17 for the home team.
2) With one exception, wins of 7 or fewer points are scored as 7-point wins and losses of 7 or fewer points are scored as 7 point losses. So a 4-point home win goes down as +7 (and not a 1) and a 1-point home loss is a -7 (and not a -4). The one exception is that road losses of 3 or fewer (and home wins of 3 or fewer) are graded as ties. So a 21-20 home victory goes down as a 0 for both teams.
3) Wins/Losses of more than 24 points are scored as the average between the actual number and 24. This is to avoid giving undue credit to teams that run up the score. So a 75-point home win goes down as a 48-point win.
Once we have a rating for each team in each game, we then adjust each result for strength of schedule. This is an iterative process, where we adjust the ratings hundreds of times (to adjust for SOS, you have to adjust for the SOS of each opponent, and the SOS of each opponent’s opponent, and so on.) in Excel. Then we produce final ratings, where the SRS rating is the sum of the Margin of Victory and Strength of Schedule in every week.
After five weeks, what are the results? As usual, the table is fully searchable (type “-0″, for example, to see a list of undefeated teams, or SEC to see all SEC teams.) Right now, the number one team is Oklahoma, with an average (adjusted) Margin of Victory of 24.6 points per game against an average opponent that is 43.3 points better than average (average includes all football teams at all levels, so all FBS teams will have a positive grade). Among undefeated teams, the only teams with tougher to-date schedules than Oklahoma are Auburn and UCLA. Below shows the ratings for all 128 FBS teams.
As always thanks to Dr. Peter R. Wolfe for providing the weekly game logs.
Again, the ratings here don’t provide near the utility they will in a few more weeks. Florida State is currently 16th, but we can expect them to rise as they play (and presumably beat) better teams. The SRS doesn’t know how good these teams actually are — no preseason information is used — all it knows is how the teams have played to date.
Once again, I’ve set up a page that shows the results of every single FBS game this season. You can view that page here. The single best performance so far this season came by BYU in week 2, when the Cougars went into Austin and defeated Texas (#40 in the SRS), 41-7. You can use that page to understand exactly how each team’s rating is derived. For example, you may wonder why Stanford is only 28th in these ratings. Well, the Cardinal got single-game ratings of 53.6 for a 7-point road win against Washington, 53.3 for a blowout of Army, 45.3 for a blowout of UC-Davis, and 44.7 for the 3-point home loss to USC. Once Stanford’s SOS increases — and a trip to South Bend next week will help do that — the Cardinal could rise in these ratings.
Finally, let’s look at each FBS team from week five, sorted from best to worst by SRS. At this point, it’s big blowouts over bad teams topping the list, but the table below is fully sortable and searchable. For example, if you sort by the SOS column (double click it to sort from best to worst teams), and type “win” in the search box, the table will sort based solely on which teams beat the best teams. In week 5, that was Texas A&M over Arkansas, Georgia over Tennessee, Washington State over Utah, Missouri over South Carolina, and Notre Dame over Syracuse. With many more high-profile games in week 6, that list will look more impressive next week.
