by Brian Fremeau

We've reached the midpoint of the season, a threshold that is significant for the weekly FEI ratings in two ways. First, we have finally shed all remnants of the preseason projected data from the formula -- all ratings from this point forward will only represent data from 2011 games. Second, we will debut offensive and defensive efficiency data for the first time this season.

One of the main reasons I wait until this point in the year to publish offensive and defensive efficiency is that I need to wait until a fair amount of connectivity between teams exists. With only a few first- and second-order connections between teams early in the year, the opponent-adjusted data can be too heavily influenced by a few outlier results. The variance in game data can be extraordinary for some teams, and the opponent-adjusted results skew significantly.

Of course, there's no magic date when college football connectivity ceases to be a concern. Week 7 is a convenient time to make the switch, but there are peculiarities in the results this week that make me wonder if the 2011 season needs a little more time to cool.

Take Wisconsin, for example. The Badgers' raw Offensive Efficiency (OE) is 1.501 through the first seven weeks of the season. In laymen's terms, that means Wisconsin's offense is producing 150 percent more scoring value than expected based on non-garbage drive starting field position. The second most efficient offense is Houston (1.037), and they are roughly equivalent to the most efficient offense at this point last season, Boise State (1.002). Wisconsin is scoring a mammoth 5.1 points per non-garbage offensive possession. West Virginia, ranked 20th in points per offensive drive (2.9) is as close to second place Stanford (4.0) as Stanford is to Wisconsin.

The following chart represents a comparison between 2011 Offensive Efficiency data through Week 7 and end-of-year 2010 Offensive Efficiency data. In each chart, teams are ordered from 1-120 along the x-axis. In addition to Offensive Efficiency data, supplemental raw drive efficiency metrics are plotted for each team. The correlations between these metrics and OE are also provided.

Pardon the expression, but Wisconsin's season to date has been off the charts. Of course, this only represents unadjusted game data. What we are truly interested in is Offensive and Defensive FEI. That's where things can get interesting for the Badgers the rest of the way.

Wisconsin has played the 115th easiest offensive schedule to date, but they'll play the toughest offensive schedule in college football the rest of the way. The Badgers haven't faced a top-40 opposing defense yet according to FEI, but they'll play four top-11 defenses down the stretch. The challenge begins this weekend on the road against DFEI No. 5 Michigan State. If Russell Wilson and company are even half or a third as efficient as they have been to date, Wisconsin will roll. But I'm thinking the Badgers' ridiculous success will come back down to earth a bit this weekend and through the rest of the year.

The opponent-adjusted Offensive FEI and Defensive FEI have their own peculiarities as well. Are we really to believe that the Miami Hurricanes have the nation's best offense? Or that the Kansas State Wildcats have the nation's best defense? There are plenty of teams that appear to be right where they ought to be, but what's with these outliers?

For Miami, their offense isn't putting up eye-popping raw stats (384 yards per game, 71st nationally), but they are much more impressive when we adjust for pace (6.6 yards per play, t-15th nationally). In terms of offensive efficiency, Miami was ...

• more efficient against the Buckeyes than all but one of Ohio State's opponents,
• more efficient against the Tar Heels than all but one of North Carolina's opponents,
• dead even with Baylor's explosive offense against common opponent Kansas State,
• and more efficient against the Hokies than any of Virginia Tech's other opponents.

Those aren't all necessarily elite defenses, but it is the kind of offensive resume that is unmatched in terms of opponent-adjusted performance. That said, I expect Miami to come back to earth a bit once more game data filters in. At this point last season, South Carolina had the nation's top offense according to FEI but settled in at 10th by the end of year.

Defensively, Kansas State has a similarly surprising profile. The Wildcats held Baylor and Texas Tech to their least efficient offensive games of the season and Kansas State had the second-best defensive effort to date against both Missouri and Miami. As you might guess, the Kansas State vs. Miami game helps trump up both teams in the opponent-adjusted ratings. Again, I'd expect Kansas State to settle in further down the rankings once more data reduces the impact of the limited results gathered to date.

FEI Week 7 Top 25

The Fremeau Efficiency Index (FEI) rewards playing well against good teams, win or lose, and punishes losing to poor teams more harshly than it rewards defeating poor teams. FEI 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. FEI represents a team's efficiency value over average. Strength of Schedule (SOS) is calculated as the likelihood that an "elite team" (two standard deviations above average) would win every game on the given team's schedule. "SOS A" represents only games played to date. "SOS B" represents only remaining scheduled games.

Mean Wins (FBS MW) represent the average total games a team with the given FEI rating should expect to win against its complete schedule of FBS opponents. Remaining Mean Wins (FBS RMW) represent the average expected team wins for games scheduled but not yet played.

Offensive FEI (OFEI), Defensive FEI (DFEI), Special Teams Efficiency (STE) are also provided, along with Field Position Advantage (FPA), the share of the value of total starting field position earned by each team against its opponents.

Only games between FBS teams are considered in the FEI calculations. These FEI ratings are a function of results of games played through October 15. The ratings for all FBS teams can be found here. You can also find OFEI, DFEI, and STE on their own pages.

Posted by: Brian Fremeau on 19 Oct 2011

14 comments, Last at 08 Dec 2012, 3:40am by john123456