Building a college football power rating model

155
 

 

 

Building a college football power rating model

For the last several seasons, I have put together college football power ratings. In concert with my home-field advantage values, I use these team ratings to create spreads for every game. That allows me to look at season win total markets, but also to have an idea of where I think a line should be in a given game throughout the season.

Power ratings can be as basic or detailed as you want them to be, depending on how much time and effort you want to dedicate to the process. My process is fairly basic, but my goal is to get ahead of some line moves on Sunday and Monday by taking positions based on my ratings for the teams. If I have a line -7 and the market has -4, I anticipate that line to move towards my line as the week goes along, which gives me some incentive to grab -4.

The measure of a good set of power ratings is to have more lines move toward your numbers than move against them. Sometimes your line will be wrong. Sometimes an injury slips through the cracks. Sometimes bettors with a lot of market influence like the other side, and the line will move in the other direction. Sometimes those bettors will be wrong. Sometimes your power ratings will be wrong.

Starting with a good foundation is important because it can be a cat-and-mouse game throughout the season. Let’s start with the foundation and then move into how to adjust and adapt as the season goes along.

I do what I consider to be “Positional Power Ratings”. I use seven positions to determine my rating for a team on a scale of basically 40-100. The Georgias and Alabamas of the world will be closer to 100. The FIUs and New Mexicos of the world will be closer to 40.

Why a 40-100 scale? I break my position groups down like this: QB, OL, DL, and coaching/special teams are graded up to 15 (60 total points). RB, WR, LB, and DB are graded up to 10 (40 total points). Therefore, a perfect score would be 100.

The position units for the top teams will be closer to the highest possible number, while the best players in Group of Five schools might lead to a rating 2-3 points away from the highest possible number. Mid-tier teams in Power Five conferences would have position groups graded similarly to the best of the best in the Group of Five.

The goal is to look at the rosters, the returning production, and the offensive and defensive schemes to develop these values. On an Air Raid team, the running backs won’t be as productive and probably won’t be a position of emphasis in recruiting. But a QB and a WR group are going to be weighted differently.

Are these an exact science and 100% accurate? Absolutely not. But, they give me a starting point for the season and something to go off as the season goes along so that I’m not blindly saying things like “this line looks too low” or “that line is too high” without having it based on anything other than opinion or conjecture.

So, let’s take the two-time reigning National Champion Georgia Bulldogs, the highest-rated team for me going into the season.

Quarterback: 13.5/15

Replacing Stetson Bennett will not be easy as Georgia looks for a three-peat. However, a program like this will recruit at a very high level. The contenders for the job, including last season’s backup Carson Beck, are going to four and five-star guys. Beck, for instance, was a four-star kid in the class of 2020. Brock Vandagriff was a four-star in 2021, while Gunner Stockton was a four-star in 2022. Even though experience is low and returning production is basically non-existent, there’s a ton of talent here, and one of them should emerge.

Running Back: 9.5/10

The Bulldogs don’t have a feature back but have a committee full of talented rushers. Kendall Milton and Daijun Edwards combined for over 1,350 yards last season, and Georgia ran for 5.5 yards per carry as a team, so this should be a very productive group again.

Wide Receiver: 9.5/10

Brock Bowers might be the best tight end in football (TE are included here), and Ladd McConkey, when healthy, has been a reliable option. There are a bunch of highly-touted recruits here, plus Oscar Delp, who was the No. 1 TE in the class of 2022.

Offensive Line: 15/15

Georgia allowed nine total sacks last season, with those 5.5 yards per carry and over seven yards per play. It all starts with the guys up front. Three starters are back, with new starters at the tackle position, but again, these are four and five-star recruits. Remember, a lot of elite programs also have a lot of elite position coaches and awesome recruiters.

Defensive Line: 15/15

If there’s anything we know about the Georgia defense, it will reload annually. The Bulldogs have allowed under 80 rushing yards per game in each of the last four seasons. They’ve allowed under five yards per play in each of the last six—just elite.

Linebackers: 9.5/10

Maybe this should be a 10/10, especially with all the special stats this defense puts up year-to-year, but Nolan Smith and Robert Beal are notable losses. Smael Mondon and Jamon Dumas-Johnson are great players, but Georgia does rotate a lot of guys in by leading by a ton more often than not.

Defensive Backs: 9.5/10

Another terrific position group. I don’t really give any team a 100 grade coming into the season because there is always turnover, even for the best teams. So, little moderations to the scores can oftentimes come in the form of the “lesser” position groups in importance.

Coaching/Special Teams: 15/15

Georgia is 29-1 over the last two seasons. There are other talented teams around the country, but few maximize their potential like the Bulldogs. Kirby Smart is one of the nation’s elites, and his coordinators and position coaches are quite good as well. This is also a perennial Top 25 team in special teams, which makes sense when the guys on those units are also four and five-star kids just waiting for the chance to be an every-down player.

Total: 96.5/100

Some nitpicking here and there, but this is the No. 1 team in the country for me. If Beck, Vandagriff, or Stockton can take the bull by the horns and make the offense hum, I’ll quickly adjust them up. We won’t find out for a little while because of the schedule, but until proven otherwise, this is the nation’s best team.

By comparison, UTSA is my top Group of Five team at 72.5, which is equal to UCF and right around teams like Tulane and Louisville.

The difference between teams is the line on a neutral field, and then I apply my home-field advantage values to make the spread.

The science of maintaining a good set of Power Ratings throughout the season is where the difficult part comes in. My process of updating them has three steps, and teams will move up or down based on three criteria – the closing spread, the box score, and injuries. That is something I’ll do throughout the season on the VSiN website. 

For now, focus on putting together a good set of initial ratings, and you can even cross-check and confirm with the lines that are already out there to make sure you have a good foundation.