FEI Week 8 Ratings
by Brian Fremeau
The Georgia Bulldogs were idle last weekend, but they took full advantage of the bye weekend to jump up a spot to No. 1 in this week's FEI ratings. The TCU Horned Frogs were ranked No. 1 last weekend and completely dominated the lowly Kansas Jayhawks, outgaining their opponent by a margin of 475 yards to 21, and 22 first downs to only four. The FEI system rating system rewarded that effort by dropping TCU down to No. 4 this week.
The way to understand what happened with the FEI ranking movement of these two teams based on the results of this past weekend is to first understand that a lot more data than just TCU's win over Kansas was added to the formula. Every game result played to date is re-evaluated each week, and movement from week to week is only in part based on a given team's new game result. If, for instance, the only game result of Week 8 was TCU's victory over Kansas, there would have been very little movement in the FEI ratings and TCU would have remained ahead of Georgia. It was the other games played over the weekend, and the resulting shift in opponent-adjusted data from previous games played this season, that moved teams up or down.
That opponent-adjusted single-game data is now available to be explored in more detail, including game ratings for overall team efficiency, offensive efficiency, and defensive efficiency. I've published this data in previous seasons and called out teams that have had multiple elite-level team performances, noting that championship-level teams regularly produce a handful or more single-game efficiency performances that rate in the 90th percentile nationally. Which teams are off to that kind of a start in 2017?
There have been 422 games played between FBS teams to date, which means there have been a total of 844 single-game performances by FBS teams. In order to qualify for the 90th percentile, a single-game performance would have to rank 84th or better in overall opponent-adjusted quality. A total of 45 teams have recorded at least one single-game performance in the 90th percentile. But only four teams recorded 20 of those 84 (24 percent) overall opponent-adjusted team efficiency single-game ratings in the 90th percentile. Those four teams, with five such performances to date apiece, are Alabama, Clemson, Ohio State, and Oklahoma State. Two other teams, Georgia and Penn State, have four apiece. Six other teams -- Central Florida, Miami, Mississippi State, Notre Dame, TCU, and Washington -- have three such performances apiece. More than half of the 90th-percentile single-game performances of the year belong to those 12 teams.
In terms of single-game offensive performances, there are more teams (50) that have recorded at least one 90th-percentile offensive performance. But only seven teams have at least three such performances. Oklahoma leads the way with six; Ohio State and Oklahoma State have five apiece; Alabama and Notre Dame have four apiece; and Penn State and Arizona have three apiece.
The opponent-adjusted wealth is distributed even more on the other side of the ball. There are a total of 61 teams that have recorded at least one 90th-percentile defensive performance, and only two defenses that have recorded at least three such performances to date -- Marshall has four, and Penn State has three.
All of this data is combined to produce the opponent-adjusted FEI team ratings, OFEI offensive ratings, and DFEI defensive ratings. But the method to produce those ratings isn't as simple as adding up the frequency of 90th-percentile performances. The very best performances could carry more weight, and a lousy performance could drag down a team's rating. And the weighting for each game is variable, depending on the team and its relative ranking with the opponent.
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The Oklahoma Sooners recorded the single best opponent-adjusted GFEI game rating of the year when they took down Ohio State 31-16 on the road in Week 2. That game represents 17.5 percent of Oklahoma's overall FEI rating, but the Sooners' loss at home to Iowa State in Week 6 accounts for 22.3 percent of their team rating. For Iowa State, their victory over Oklahoma as well as their losses to Iowa and Texas all individually receive 20.4 percent of the weight in the Cyclones' team rating.
The top 18 teams in the FEI ratings all have multiple GFEI single-game performances in the 90th percentile on their resume, or have zero GFEI single-game performances lower than the 50th percentile on their resume, or both. At No. 19, Mississippi State has three of each -- dominant wins over Louisiana Tech, LSU, and Kentucky all rank better than 90 percent of all other single-game performances nationally, and their blowout losses to Georgia, Auburn, and a win over BYU all officially rank as below-average performances.
As we so often do, it's worth mentioning Alabama and noting their single-game overall, offensive, and defensive performances this year. The Crimson Tide are merely ranked No. 5 in this week's FEI ratings because they aren't getting the opponent-adjusted boost others at the top are getting. They have looked great, but they have played the 98th-toughest schedule to date. They have only one win over an FEI top-30 opponent (Florida State is hanging on at No. 27) and only two wins against the FEI top 50. That said, they are the only team in the nation that hasn't had a single-game overall, offensive, or defensive performance this year ranked outside the 50th percentile. The Crimson Tide have the highest floor, and they'll be at the top of the overall ratings by season's end if that continues.
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FEI 2017 Week 8 Ratings
The Fremeau Efficiency Index (FEI) is a college football rating system based on opponent-adjusted drive efficiency. Approximately 20,000 possessions are contested annually in FBS vs. FBS games. First-half clock-kills and end-of-game garbage drives and scores are filtered out. Game efficiency (GE) is a measure of net success on non-garbage possessions, and FEI opponent adjustments are calculated with special emphasis placed on quality performances against good teams, win or lose. SOS ratings represent the average number of losses an elite team (two standard deviations better than average) would have against the team's entire schedule.
Offensive FEI (OFEI) is value generated per drive adjusted for starting field position and opponent defenses faced. Defensive FEI (DFEI) is value generated per opponent drive adjusted for starting field position and opponent offenses faced. Special Teams Efficiency (STE) is the average value generated per possession by a team's non-offensive and non-defensive units.
|16||North Carolina State||5-1||.173||.115||24||1.92||15||3.15||14||2.07||56||-.10||121|