These rankings are created with predictions in mind. This might seem an odd statement, as the very word rank implies the ordering relates to quality, and thus higher ranked competitors should always be "better" than the lower ranked. However, college football is an arena where few have ever agreed on anything. It has "mythical" national champions, and many seasons have ended with more than one team undefeated. It is its own special case in the sports world.

Thus, the Entropy college football ratings for past seasons are a different animal. For the past, I have attempted to create an algorithm that would accurately rank teams, but that would also make concessions to undefeated teams that might not have been the best team, but probably deserved recognition as the mythical national champion.

For the NFL, college basketball, and the NBA, all power ratings past and present are designed for predictive accuracy. The same algorithm used for those leagues is used for college football while a season is in progress. Then, after the last bowl game, the "champion recognition" algorithm is applied as the final judgement on the season.

With that important distinction out of the way, here's the rest of the story...

There are no authoritatively correct rankings, period. It takes a while to appreciate this, but after enough study of college football (or any competition), it becomes clear that any team really can win on any given day, and winning a dozen games does not prove a team the "best." There is a tremendous amount of luck involved in football. Twelve games is not a large enough sample to even out the luck - and that is what makes college football rankings an amazing challenge, and one of the most interesting phenomena in all of sports, in my opinion.

I have devoted much time to studying scores over the history of the game. I crafted the system trying to come up with what seemed the best ratings for all seasons. If any team appeared far out of place in any season, I went back to the drawing board and questioned everything. It was a long, frustrating process, but in the end a satisfying experience. I think the ratings are now as close to "right" as can be found, but others must be the judges of that.

The goal is twofold: high quality predictions during the season, and ratings that make sense to most fans at the end of each season. Explaining in detail how this is done would bore most people to tears, so here's a quick summary...

Quick summary:

1. Scores, locations, and dates of games are the data input.
2. Home field advantage adjustments are applied.
3. Power rating values are on a game point scale. Approximate predictions may be made by subtracting a team's power rating from that of its opponent, and then adding 3 points to the home team (4 for basketball). Predictions published on the site are produced through a more complex method.
4. Pre-season ratings are a component of the ratings until about the mid-point of the season.
5. Quoted W-L-T records include only games played against other teams involved in the ratings. If your team is missing a game on its record, it is because the game was against a minor opponent that is not recorded as playing any other team in the rankings that year.
6. For 1977 and later, only Division 1A teams are listed. However, many non-1A opponents are included in the calculations.
7. On forfeits: If the game was completed, it is used in the calculations with the score that was recorded. If the game was not completed, then it is completely ignored.

The ratings list for the current season has columns called "offen" and "defen." These give the average points scored and allowed by the team, not including overtimes.

Random Bits:

Predictive systems are not primarily concerned with determining which teams deserve the glory of a "championship." Rather, the goal is to guess at which team would be more likely to win an as yet unplayed game. Therefore, offense should never be taken over a ranking position.

Recent rankings that cause the most headaches are found in 1980, 1997, 1998, and 2002. Those seasons each had at least one major team go undefeated and untied without being dominant in many of their games. The teams are Georgia in 1980, Michigan in 1997, Tennessee in 1998, and Ohio State in 2002. Some of these teams appear ranked as far down as #9 by various ranking systems I have checked over the years. Surely these teams deserve recognition and glory, and yet many mathematical systems fail to give them at least reasonable rankings. I do not think any of these teams should be ranked lower than #5. Happily, Entropy puts two of them at #1 (Tennessee '98 and Ohio State '02). For more on these teams, click here.

Nothing is permanent or easy to pin down. I love the notion that anything can happen, and to appreciate it, I like to highlight this game. Then I encourage everyone to learn about the breakdown of transitive logic. These two short pieces will tell you pretty much everything you need to know - completely "accurate" rankings are impossible. (And that's why I like doing this.)

Few computer ratings designers completely divulge their method, and for good reason. It is a lot of work to put together an interesting system. Therefore, I believe the best philosophy is to ask visitors to consider the ratings for many past seasons, and judge for themselves which system does the best job.

Every fan has their own conceptions on how teams should be ranked. Therefore, I am working on a rankings litmus test that will hopefully have standards acceptable to almost everyone.

If these rankings can spotlight some teams that did not get the attention and glory some believed they deserved, I'm happy. On the other hand, some teams are bound to be slighted. I simply point out that this is inevitable, and invite critics to try to do better! ;)

The Entropy CFPOOL confidence values are determined by estimated odds of winning, not predicted margins of victory.

Enjoy, and feel free to send feedback and questions...

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