At this point in season, three weeks into the current year’s Gridiron Power Index (GPI) we usually notice how the human opinion polls (FCS Coaches Poll - FCP and The Sports Network Poll - SNW) start to become near replicas of each other and how the GPI dramatically differs from them both.

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Of course this difference completely relates to the usage of top computer rankings and both polls in the GPI, and the polls by themselves. Our table at http://www.collegesportingnews.com/content.php?775-2012-FCS-Rankings displays the top 25 of each side-by-side.

Since we know the components are different, what else may be the reason for the disparity between them?

The disparity mainly lies in the computer rankings and how they factor in each game (and score in those that use margin of victory) and strength of schedule. It would require superhuman abilities to rank all 122 FCS squads so precisely so our trusty computers do their job in tabulating the results in an unbiased method as possible. All the teams are adequately interconnected by opponents to analyze the wins, losses and point differentials in such a way that most humans cannot objectively achieve.

What are the main top 25 differences now between the GPI and the polls?

If you put the GPI next to each poll at a glance there are several points that pop out.

+ The GPI agrees on only three teams ranking in both polls.
+ There are two additional teams where the ranking of the FCP matches the GPI.
+ The GPI ranks three teams that neither poll ranks (each an MVFC squad).
+ There is an additional team in each poll that the GPI ranks and the poll doesn’t.

A simple way to get an overall idea how the GPI and the polls differ is to subtract the poll ranking from the GPI to get either a negative number (poll under-ranking) or a positive number (poll over-ranking) in relation to the GPI.

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A College Sporting News Special Report