DubStat’s Elo Rating system is derived from the original system developed in the 1960’s by Physic Professor, Arpad Elo, in order to rate the skill level of chess players.
However, DubStat’s system has some key adjustments that make it suitable for football.
See What are Elo Ratings and How do they Work? for an introduction into Elo Ratings.
Factors of the Elo Rating System
- Data Source
- K-factor
- Scaling factor
- Win Factor (W-Factor)
Data Source
In order for an Elo system to work, there must be a centralized database of match results.
The data used to calculate DubStat’s Elo ratings come from JoeEitel.com. Joe’s site contains results throughout Ohio and bordering states. He does an excellent job of uploading results on a weekly basis throughout the season.
K-factor
The k-factor is the maximum amount of Elo points a team can gain (or lose) at the conclusion of a game.
In DubStat’s system, k-factor is 100 points.
While 100 points is the most a team can gain (or lose), a much smaller number is usually achieved based on a few other factors.
Scaling Factor
The scaling factor determines how likely a team is to win based on the difference between their Elo rating and their opponent’s Elo rating.
For example, the algorithm may calculate that Team A (1700 Elo Rating) has a 90% chance of winning against Team B (1600 Elo rating).
If Team A wins, they would only be eligible to gain 10% of the k-factor, or 10 points (10%*100 =10). Team B would be eligible to lose 10 points.
If Team B wins, they would be eligible to receive 90% of the k-factor, or 90 points (90%*100 = 90). Team A would be eligible to lose 90 points.
However, there is one more factor that impacts the number of Elo points a team gains (or loses) at the conclusion of a match.
W-factor
The w-factor is custom to DubStat’s rating system. This factor accounts for the margin of victory.
The w-factor determines what percentage of the max points (k-factor) should be available after a win.
If a team wins by 50 points, they receive the full allotment of points, while a team who only wins by 1, they will receive a small percentage of the available points.
What is a good Elo rating?
An Elo score of 1500 is considered an “average score”. The following table is, in general, a good representation of how Elo ratings compare to achievement levels.
| Elo Rating | Achievement Level |
| 1600-1700 | Top 25 Team |
| 1700-1800 | Top 5 Team |
| 1800+ | State Champion Contender |