I-AA Grouping System

However, 2006 saw the expansion of the schedule from 11 games to 12 games. In response to this addition of a 12th game, many I-A teams have added I-AA teams to their schedules. The significantly higher number of I-A vs. I-AA games has created three problems for the complete exclusion of I-AA results. First, a larger fraction of results are ignored. Second, the increased competition between the two divisions has increased the parity between them, making I-AA victories more likely. Third, the larger number of games makes the previously "flukish" win by a I-AA more likely, just statistically. These three issues demand that a good ranking system for I-A somehow account for the games against I-AA.

The Colley Matrix has addressed this problem in a straight-forward way that does not change the fundamental mathematics of the Colley Matrix rankings system. Here is how it works.

1. Selecting only games involving two I-AA teams, rank the I-AA teams using the normal Colley Matrix system.
2. Form groups of I-AA teams.
• Determine the average number of games played by I-A teams.
• Starting at the top of the ranked list of I-AA teams, begin adding to the group until the number of games that group has played against I-A is about the same number of games most I-A teams have played so far this season.
• When the group is "full," move to the next group and repeat previous step.
• Avoid the problem that the last group may be underpopulated by iteratively "demoting" teams from other groups until the distribution of I-A games played by each I-AA group is fairly even.
3. We now have groups of I-AA teams that have played about the same number of games against I-A as most I-A teams have played this season.
4. Add these groups into the list of I-A teams.
5. Rank the I-A teams plus the I-AA groups as normal with the Colley Matrix ranking system.