Part II of our injury series: Do some injuries become more common later in the NFL season? And has the NFL succeeded in cutting down on concussions?
24 Oct 2013
by Brian Fremeau
Last weekend featured a flurry of upsets that shook up the polls. Eight teams ranked in the Associated Press top 20 heading into last weekend lost. Five of those losses were to previously unranked opponents. Missouri surged into the BCS national championship picture with perfect timing –- a dominant win over Florida coupled with the poll carnage vaulted the Tigers to No. 5 in the BCS standings released on Sunday. FEI has ranked the Tigers in the top 10 in four of the last five weeks, and Missouri held steady at No. 3 following the win over the Gators. As discussed in yesterday’s ESPN Insider piece, Missouri has almost locked up an SEC title game berth and has a decent chance to run the regular season table.
The FEI love for the Pac-12 continues as well. Stanford defeated previously unbeaten UCLA and slid up to No. 2, though the margin between Stanford, Missouri, and No. 4 Oregon is practically negligible. Arizona State’s dominant win over Washington gave the Sun Devils a big boost. FEI still loves the Utah Utes, dropping them only to No. 6 overall following a loss at Arizona.
Hopefully I won’t have to explain the Utah love every week, but opponent adjustments are the biggest factor working in their favor. Utah has played FEI No. 2 (won by six), No. 10 (won by seven), No. 17 (lost by seven), No. 20 (lost by three in OT), No. 23 (lost by 11), and No. 39 (won by four). They have played six FEI top-40 opponents, more than any other team. 17 FEI top-25 teams have played three games or fewer against that level of competition.
The Utah love is related to the love for all their other opponents, of course. But if we assume those opponent ratings are "right," should we be surprised that the No. 6 team is only 3-3 against that slate? The likelihood that a team with Utah’s FEI rating would be 3-3 against the six opponents it has faced thus far is only 22.1 percent. A team with Utah’s rating should be 4-2 or better (69.9 percent likelihood). A team with Utah’s rating would have an 8.0 percent chance of having four or more losses at this point.
In a way, the FEI formula "solves for" the win likelihoods as part of the weekly ratings. The Mean Wins columns in the FEI table published each week identify the average total wins and remaining wins a team with the given rating should be expected to have. The difference between the two is equal to the average total wins that team is expected to have to date.
Utah projects to have 7.7 mean wins versus FBS opponents, and projects to have 3.7 mean wins remaining based on their FEI rating and the ratings of their upcoming opponents (games against No. 27 USC, No. 11 Arizona State, No. 4 Oregon, No. 71 Washington State, and No. 106 Colorado). The difference, 4.0 wins, is the total Utah should have to date. The difference between their expected mean wins and their actual wins (three) usually relates to less predictable factors. As we mentioned last week, Utah would have five wins if not for turnovers.
One common observation about the FEI ratings is how much circular logic can boost whole sets of teams. Utah is highly-ranked because Stanford and BYU are highly-ranked, and those teams are highly-ranked in part because Utah is highly-ranked. We can recalculate the FEI ratings by dropping each of these three teams and its games out of the formula to see the influence each team has on one another.
|FEI Ratings Without Utah||FEI Ratings Without Stanford||FEI Ratings Without BYU|
|5||Stanford||.282||5||Arizona State||.272||5||Florida State||.277|
There certainly is some shuffling when we remove games from the formula, but Stanford and BYU are not being propped up by Utah. The Cougars are a top-10 team according to FEI with or without having played Utah. The Cardinal are a top-5 team with or without having played Utah.
The Utes, however, drop out of the top 10 in both the "remove Stanford" and "remove BYU" versions of the FEI ratings. Utah ranks in the top 20 in both of those outputs, however, even as a team with only two FBS wins in those scenarios.
The key for Utah is that they have recorded two wins that FEI measures as very high quality, and that they have been competitive in all of their games. That is precisely what the formula was designed to reward. If they are competitive against their remaining schedule (three more top-40 games), they will likely remain highly ranked in FEI.
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 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.
These FEI ratings are a function of results of games played through October 19th. The ratings for all FBS teams can be found here. Program FEI (five-year weighted) ratings and other supplemental drive-based data can be found here.
6 comments, Last at 26 Oct 2013, 1:48pm by Brian Fremeau