Vegas likes Alabama a lot more than it likes LSU.
The Simple Rating System is a set of computer rankings focused on only two variables: strength of schedule and margin of victory. I published
weekly college football SRS ratings each week last season, and you can read more about the SRS there. Last month,
Jason Lisk of the Big Lead took the Las Vegas point spread for each NFL game to come up with a set of power rankings; I stole Lisk’s idea and used the same point spreads to create
implied SRS ratings for every NFL team. The idea is that if the 49ers are a 10.5-point neutral site favorite over the Jaguars, that’s one data point that implies that Las Vegas views San Francisco as 10.5 points better than Jacksonville. By taking every data point, and
using Excel to iterate the ratings hundreds of times, you can create a set of implied team ratings.
Last week, the Golden Nugget released the point spreads for 248 college football games. By using the same process, those point spreads can help us determine the implied ratings that Las Vegas has assigned to each team.
We don’t have a full slate of games, but we do have at least 1 game for 83 different teams. Theoretically, this is different than using actual game results: one game can be enough to come up with Vegas’ implied rating for the team. That’s because once we’re confident in Oklahoma’s rating, Tulsa being 18-point underdogs in Norman gives us a good estimate for how Vegas views Tulsa. I assigned 3 points to the road team in each game in coming up with the implied SRS ratings. For example, Arizona is an 11-point favorite on the road against California. So for that game, we assume Vegas believes the Wildcats are 14 points better than the Golden Bears; if we do this for each of the other 247 games, and then iterate the results hundreds of times, we can come up with a set of power ratings.
Unsurprisingly, Alabama comes out as the highest-rated team. The Crimson Tide are being rated as 19.6 points better than “average,” although average isn’t really a concept with much meaning here. The SRS rating has little meaning in the abstract, but is useful to get a sense of the Crimson Tide’s rating relative to the rest of the teams. If Alabama is 10 points better in the SRS than a team, that means Alabama would be projected as a 10-point favorite on a neutral site. In the table below, I’ve included the number of games for which we have point spreads for each team on the far left. The “MOV” column shows the home field-adjusted average point spread for that team, the “SOS” column shows the average rating of each team’s opponent (for only the number of games for which we have lines), and the “SRS” column shows the school’s SRS rating.
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