2023 College Football Rankings #2 - What Week 5 Hath Wrought

Week 5 (counting from Week 0) was another week where we learned a lot about where the field is headed. Some of the notable results included:

• #21 Notre Dame ruining ESPN College GameDay's first visit to Durham pushing past #14 Duke

• #24 Oregon State after a tough loss at Washington State handed #13 Utah its first loss.

• #48 USC, with its Charmin-soft schedule to date, got a big road win at #15 Colorado

• #2 Texas knocked #30 Kansas from the unbeatens with the help of Jaylon Daniels, the Jayhawks' marvelous QB being a late scratch.

• #16 Ole Miss winning a barn burner with LSU and pushing LSU into two-loss land for now. Will LSU still be able to make my fake bracket? It's a tall order.

• #50 Clemson thumps #23 Syracuse. Though 3-2, Clemson has played a reasonably tough slate.

Putting this into the modeling machine, and we get this:

Now, you can sort of see how the rankings change as we learn more about the season. Notre Dame moved up to #8 after defeating Duke. But Ohio State ALSO moved up because of the increased value of their road win. Now, we expect the jumps to shrink as the season goes (as well as the spreads between the 20th and 80th round robin win %), but the volatility so far is a feature, not a bug. Again, with the season still early - we will defer to unbeatens where it makes sense.

And now, the 12 Team Bracketology

Conference Champions:

• ACC: Miami-FL (4)

• Big 12: Texas (1)

• Pac 12: Washington State (3)

• Big Ten: Ohio State (2)

• SEC: Missouri (17)

• MAC: Miami-OH (44)

• MWC: Air Force (32)

• Sun Belt: James Madison (34)

• American: Memphis (41)

• CUSA: Liberty (38)

At Large:

• Penn State (5)

• Michigan (6)

• Oregon (7)

• Florida State (11)

• Oklahoma (12)

• USC (13)

Just off the bubble

• Washington (16)

• North Carolina (20)

• Maryland (25)

• Georgia (26)

Bracket - moving first round matches as needed to avoid intraconference 1st rounds

• (1) Texas

  • (8) Florida State v (10) USC

• (4) Miami-FL

  • (5) Penn State v (12) Air Force

• (2) Ohio State

  • (7) Oregon (9) v Oklahoma

• (3) Washington State

  • (6) Michigan v (11) Missouri

2023 College Football Rankings #1 - Starting the Voyage of Discovery

I have been doing these rankings since 2008 - at least in the blogosphere. I have tinkered with the formula a lot. But I think I've found something I am happy with the last few years. Here are some of the basics:

• The engine is a Bradley-Terry based model. This is basically a giant logistic regression using the results to determine team ratings. Thank god for R.

• Now instead of using straight win-loss, I use a formula of 0.8 for a win, and up to 0.2 based on margin of victory. The margin of victory is lognormal, so there are diminishing returns for blowouts. The model can be stumped by winless and unbeaten teams so this helps that out.

• The ratings that come out of this end up being log-odds relative to a base team. Since I entered the teams in alphabetical order, the base team is Air Force. So if Air Force's rating is 100, a rating of 2000 for a team means a team would win 20 times against Air Force for each Air Force victory.

• Using these ratings (and their variance), I ran a Monte Carlo Simulation over 10,000 trials where every team plays the other. This results in a Round Robin winning percentage.

• Then I borrowed a concept from how the NCAA ranks hockey teams - a pairwise comparison. Each team is compared against each other team on A) round robin win pct, B) record v common opponents, C) head to head. The team with the most number of pairwins is #1. Now, as a practical matter, round robin win % is the driving factor - but doing this means that teams that do well in conference or in a head to head result can potentially leapfrog a position or two here and there.

Whew. So with all of that, 4 games in is a good time to put the first rankings out. There is some decent strength of schedule record. Now, each week with rankings like these - the teams move but we also learn more about the season at large. One thing I have included is the 20th and 80th percentile win % numbers, so you can see the confidence of the model.

Ultimately, no ranking is a be-all and end-all. I think stuff like this is more like a "better RPI/NET" which can guide discussions for a committee seeding model. To that end, this space will also do a 12-team playoff based on these rankings.

Obviously, this does not match the AP poll. But remember that the model only knows what has happened this year. There are no priors about the teams. Georgia's #26 rating is driven entirely by who they haven't played. These rankings will change as more data comes in!

For a 12-team bracketology, it'd work something like this. While there are some highly rated 1-loss teams, that one loss is a loss to a team above them in the rankings. The error bars are big enough to defer to unbeatens for now where possible.

Conference Champions:

• ACC: Miami-FL (1)

• Big 12: Texas (2)

• Pac 12: Oregon (3)

• Big Ten: Penn State (5)

• SEC: Missouri (12)

• MAC: Miami-OH (27)

• MWC: Air Force (42)

• Sun Belt: Georgia State (35)

• American: Memphis (38)

• CUSA: Liberty (59)

At Large:

• Washington State (4)

• Ohio State (6)

• Washington (7)

• Michigan (8)

• Oklahoma (11)

• Utah (13)

Just off the bubble

• Duke (14)

• Maryland (18)

• Florida State (19)

Bracket - moving first round matches as needed to avoid intraconference 1st rounds

• (1) Miami-FL

  • (8) Michigan v (9) Oklahoma

• (4) Penn State

  • (5) Washington State v (12) Miami-OH

• (2) Texas

  • (7) Washington (10) v Missouri

• (3) Oregon

  • (6) Ohio State (11) v Utah

Wilkommen - Let's Try This Again

No, this is not the first time I've done blogging. But it has been long enough that it felt right to start from scratch. So, here is my heartfelt attempt to start writing again - at least once a week hopefully. I've done college football rankings in the past - so I expect that to continue apace here. But otherwise - this space will discuss sports, culture, maybe a little bit of personal stuff (like that game show in the blog header). Anyway, let's see what happens.