Methodology - 2023-24 Big Eight Football

Updated April 21, 2024 at 04:14 PM

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The 2023-24 Big Eight Conference Football (Varsity) Rankings & Projections use a custom system I created called CHEsS, which stands for Conditional High-School Evaluation (Sports) System. The system is loosely based on something like an Elo model, where it uses the opponent's win-loss record to determine the number of points a team should get from a win or loss. This is explained in more detail below.

Team Ratings

CHEsS assigns each team in the Big Eight a numerical power rating based on their performance. Because this is the first year of the model for football, each team starts at a base rating of 1000 at the beginning of the season. After that, their ratings are increased or decreased in accordance to their wins and losses, as shown below. Essentially, each game either adds or removes points from a team's rating, changing their overall power score.

How Ratings Are Calculated After Games

Every team's rating is adjusted after each game they play in. First, their opponent's record is factored in as a win percentage for the base points the team can earn. For example, if Madison Memorial is playing Middleton, and Middleton has a perfect record, Madison Memorial can earn 100 points just by winning. But if Middleton has a 62% win rate, and Madison Memorial can earn a base of 62 points, they can earn the remaining 38 depending on the margin of victory. The MOV factor for football is calculated a little differently than it is for hockey. Instead of just being 0.X times the remaining points, where X is the goal difference/MOV in the game, it is 0.X where X is the difference in actual scores. (A 14 point lead in a football game would be two scores, because you need to score at least two different times.) Then, it is (100-Base Points)*(MOV/10). The base and MOV together give us the total number of points to be added to the team's rating.

Losses

Losses work a little bit differently. For a loss, a team gets no base points, regardless of their opponent's record. However, they can lose points depending on the margin of victory. The only exception to this is when they play a perfect-record team, where they would generally be expected to have no chance anyway. The same MOV factor formula is used for losses, which usually results in smaller, negative adjustments.

Individual Game Projections

Probabilities are generated for each in-conference game (any game where both teams are in the Big Eight) based on the two teams' respective CHEsS power ratings. The idea is that this will offer a reasonable and accurate reference point when looking at the likelihoods of teams winning a conference matchup. The formula shown below is used for calculating the probability of a team winning.
(1/(1+(10^(((OpponentRating)-(TeamRating))/750))))*100
The only other factor here is that the home team gets a 50 point boost to their rating when calculating the matchup probability. Otherwise, that's all there is to it!