by Brian Fremeau

We're nearly halfway through the 2009 college football season, and what do we know? Better yet, how does what we know differ from what we thought we knew six weeks ago?

Only 13 of the current FEI top 25, and five of the top 10, were ranked as highly in the FEI projections at the start of the year. Florida has held onto the top ranking in FEI throughout the young season, but the Gators haven't yet performed at their stratospheric projected level and are clinging to a relatively narrow rating margin over No. 2 Alabama. No non-BCS teams appeared in the top 30 projected FEI; TCU and Boise State now reside among the top 10.

This is the final week in which Projected FEI data is factored into the FEI ratings, so it's a good time to examine the projections and recalibrate season expectations going forward.

By some measures, the projected data has performed pretty much as expected. Each week, the FEI ratings are used to produce Projected Win Expectations (PWE) for all future games. The weekly FEI Forecasts are designed to project the score at the conclusion of non-garbage possessions in a game, and PWE represents the likelihood of victory for the projected game winner. Table 1 provides a breakdown of the relationship between PWE and actual game outcomes so far.

For some context, teams that are favored by 1-3 points according to Vegas (similar to 50-55 percent PWE) win about 54 percent of the time. This season, such teams are only winning at a 38 percent clip. Some sample sets of picks have performed well -- FEI is 31-17 (0.646) against the spread in games in which it projects the Vegas underdog to win outright; but overall, FEI Forecasts have been very pedestrian against the spread this year (.495). A quick scan of the performances of other computer rating systems suggests that the overall PWE straight-up record (.733) is off to a relatively good start. (Keeping pace with Bill Connelly's blazing S&P+ predictions is proving to be a much more lofty benchmark).

Based on PWE data for the entire the season, the FEI projections also provided a projected number of "Mean Wins" for every team -- the best approximation of each team's wins according to their own projected strength and that of their opponents. Though there has been plenty of turbulence in the FEI ratings over the first six weeks of 2009, roughly half of all teams have posted a record within 0.5 victories of their projected Mean Wins to date, and 75 percent have played to within one game. The biggest surprises are provided in Table 2.

Florida State is off to its worst ACC conference start ever (0-3) but is still hanging around just outside the FEI top 25. Its losses to No. 4 Miami, No. 12 Georgia Tech, and No. 14 South Florida were respectable (if gut-wrenching) and the Seminoles' blowout of BYU balances the loss to Boston College. Even though Bobby Bowden's team hasn't met its Mean Wins projection to date, the weakened ratings of several teams on the back half of their schedule has opened the door to salvage a modest record this year.

At the top of the table, Idaho has pulled itself out from the depths of despair (FEI projected the Vandals at No. 120 out of 120 teams), but the team still must face their toughest WAC opponents -- Nevada, Fresno State, and Boise State -- over the next month. Cincinnati travels to undefeated South Florida on Thursday night. If the Bearcats pass that test, Big East boredom may be their biggest obstacle to an undefeated campaign.

Week 6 FEI Top 25

The principles of the Fremeau Efficiency Index (FEI) can be found here. Like DVOA, FEI rewards playing well against good teams, win or lose, and punishes losing to poor teams more harshly than it rewards defeating poor teams. Unlike DVOA, it is drive-based, not play-by-play based, and it is specifically engineered to measure the college game.

FEI is the opponent-adjusted value of Game Efficiency (GE), a measurement of the success rate of a team scoring and preventing opponent scoring throughout the non-garbage-time possessions of a game. Like DVOA, it represents a team's efficiency value over average. Strength of Schedule (SOS) is calculated as the likelihood that an elite team would win every game on the given team's schedule.

Only games between FBS teams are considered in the FEI calculations. Since limited data is available at the beginning of the season, the ratings to date are a function of both actual games played and projected outcomes based on the 2009 Projected FEI Ratings. The weight given to projected outcomes will be reduced each week until mid-October, at which point the projections will be eliminated entirely. This is the final week in which projected data remains part of the calculations.

ALSO: FEI ratings for all 120 FBS teams are now listed in the stats page section of FootballOutsiders.com. Click here for current ratings, or here for 2008 ratings.

Posted by: Brian Fremeau on 14 Oct 2009

13 comments, Last at 15 Oct 2009, 11:36pm by Corey