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» Seventh Day Adventure: Week 13

The biggest game this week is the Iron Bowl, where the playoff hopes of Alabama, Auburn, and Georgia hang in the balance.

27 Oct 2015

FEI Week 8: The First First Down

by Brian Fremeau

The Clemson Tigers pasted the Miami Hurricanes on Saturday by a final score of 58-0, the most lopsided loss in Miami history and one of the most dominant performances of the 2015 season. The Tigers were already the No. 1 team in the nation according to the FEI opponent-adjusted drive efficiency numbers coming into the weekend, and this game only affirmed their position. The FEI rating differential between Clemson and No. 2 Stanford is currently larger than the rating differential between Stanford and No. 14 Michigan State. Clemson has completely separated from the pack.

The Tigers rank 14th in opponent-adjusted offensive efficiency and third in opponent-adjusted defensive efficiency, and Saturday's victory was fueled by both sides of the ball. Clemson led 45-0 through the first 21 possessions of the game, and the FEI game splits credit 24.1 points of scoring value to the offense and 21.2 points of scoring value to the defense. Clemson's offense possessed the ball six times in the first half and scored five touchdowns, and the defense chipped in another score on an interception return. Miami's offense had drives of 56, 15, 8, 5, 0, 0, and 9 yards in the first 30 minutes of play.

The Tigers' only first-half possession that did not result in a touchdown was a three-and-out on a drive that started on their own 1-yard line. In other words, when Clemson got a first down on drive, they also reached the end zone. A few years back, a reader inquired about the importance of the first first down of drives for certain teams -- how often do offenses turn a first down on a drive into a touchdown?

The Baylor Bears currently lead the nation in offensive touchdown percentage, reaching the end zone on 62.1 percent of non-garbage drives. When the Bears get a first down on a drive, their possessions lead to a touchdown 71.9 percent of the time, also the highest rate in the nation. On average, the touchdown rate after a first down for a team is 9.4 percentage points better than that team's touchdown rate counting all possessions, so Baylor's rate increase is nominal. Fresno State, Appalachian State, and Utah State rely on the first first down more than all others, each increasing its touchdown rate by more than 15 percentage points after earning a first down.

Another way to cut this data is to combine first down rate (the percentage of drives that earn at least one first down or touchdown) with post-first down touchdown rate. Clemson either went three-and-out or scored a touchdown on each of its first half possessions against Miami, a 100 percent "boom-or-bust drive rate" for the half. Which teams have the highest boom-or-bust drive rates for the season? (TDRaFD is the touchdown scoring rate on drives that earn at least one first down).

Boom or Bust (BoB) Offensive Drive Rate Top 15
Rk Team FBS
Rec
BoB OFD Rk TDR
aFD
Rk
1 Baylor 6-0 .856 .864 4 .719 1
2 Navy 4-1 .820 .786 28 .606 2
3 Appalachian State 5-1 .810 .690 85 .500 12
4 Fresno State 1-6 .802 .539 128 .341 78
5 Utah State 3-3 .786 .667 99 .452 22
6 USC 4-3 .761 .773 36 .534 8
7 Marshall 6-1 .753 .622 119 .375 55
8 Western Kentucky 6-2 .752 .798 22 .549 5
9 Georgia Southern 4-2 .751 .738 55 .489 15
10 South Florida 3-3 .750 .667 100 .417 33
11 Bowling Green 6-2 .744 .843 7 .587 3
12 Texas State 1-4 .740 .638 113 .378 53
13 Florida 6-1 .731 .705 73 .436 25
14 Northern Illinois 4-3 .730 .689 87 .419 31
15 Nebraska 3-5 .729 .676 97 .406 38
Boom or Bust (BoB) Offensive Drive Rate Bottom 15
Rk Team FBS
Rec
BoB OFD Rk TDR
aFD
Rk
114 Louisiana Tech 4-3 .534 .819 13 .353 69
115 Akron 2-4 .529 .738 56 .267 107
116 Ohio 4-3 .528 .770 39 .298 91
117 Boston College 1-5 .526 .582 125 .109 128
118 Florida Atlantic 1-6 .518 .720 66 .239 113
119 Wisconsin 6-2 .517 .786 29 .303 90
120 Kent State 2-5 .510 .613 121 .123 127
121 Central Florida 0-7 .507 .633 114 .140 124
122 Illinois 3-3 .503 .747 50 .250 112
123 Kansas 0-6 .502 .706 72 .208 116
124 Charlotte 1-5 .480 .647 110 .127 126
125 Connecticut 2-5 .461 .776 32 .237 114
126 Vanderbilt 2-4 .428 .701 76 .130 125
127 North Texas 0-6 .426 .723 65 .149 123
128 South Carolina 3-4 .361 .836 9 .197 117

The top of this list is a hodge-podge of very efficient offenses (Baylor) and very inefficient offenses (Fresno State). The extremes are most interesting, of course. Appalachian State ranks 85th in avoiding three-and-outs, but 12th in generating touchdowns after earning a first down. Marshall ranks 119th in avoiding three-and-outs and jumps up to 55th in touchdown rate after a first down. All the way down at the bottom is South Carolina -- very good at avoiding three-and-outs this year, but very bad at turning those drives into touchdowns.

What about defenses and their boom-or-bust drive rates -- that is, the boom-or-bust rates of their opposing offenses?

Boom or Bust (BoB) Defensive Drive Rate Top 15
Rk Team FBS
Rec
BoB OFD Rk TDR
aFD
Rk
1 Air Force 3-3 .871 .603 7 .474 112
2 Louisiana Lafayette 1-4 .863 .650 18 .513 119
3 New Mexico State 0-7 .825 .778 96 .603 126
4 Central Michigan 3-4 .814 .623 16 .438 97
5 Indiana 3-4 .808 .684 35 .492 115
6 SMU 1-5 .807 .775 93 .582 125
7 Eastern Michigan 1-7 .798 .819 116 .618 128
8 Oregon State 1-5 .782 .738 68 .521 120
9 North Carolina State 4-2 .775 .567 2 .342 55
10 Texas State 1-4 .772 .836 122 .609 127
11 UTEP 2-4 .771 .739 69 .510 118
12 Notre Dame 6-1 .770 .622 15 .392 80
13 Rice 3-3 .764 .785 101 .549 122
14 Maryland 1-5 .763 .737 66 .500 117
15 Fresno State 1-6 .757 .819 117 .576 124
Boom or Bust (BoB) Defensive Drive Rate Bottom 15
Rk Team FBS
Rec
BoB OFD Rk TDR
aFD
Rk
114 Florida Atlantic 1-6 .519 .795 107 .314 44
115 Colorado 3-4 .516 .822 119 .338 54
116 Syracuse 2-4 .509 .853 125 .362 64
117 Vanderbilt 2-4 .504 .676 31 .180 8
118 Appalachian State 5-1 .498 .702 44 .200 13
119 Missouri 3-4 .496 .683 33 .179 7
120 North Carolina 4-1 .495 .755 80 .250 19
121 Florida State 6-1 .491 .716 53 .208 17
122 Ohio 4-3 .491 .750 76 .241 18
123 Iowa 6-0 .475 .685 37 .160 5
124 Kentucky 3-3 .471 .844 123 .315 45
125 Northwestern 5-2 .455 .738 67 .194 11
126 Georgia State 2-3 .433 .847 124 .280 33
127 Mississippi State 5-2 .419 .775 95 .194 12
128 Toledo 7-0 .375 .772 92 .148 2

Again, the list is a mix of strong and weak defenses. It is interesting to note that only two of the teams on the high boom-or-bust defensive drive rate list have a winning record against FBS opponents -- North Carolina State and Notre Dame. More research would need to be done to understand whether the boom-or-bust rates are a function of a team's style of play (i.e., aggressive defense produces high three-and-out rates but lots of points) or if some of the results are merely coincidental. Defensive rates could be a function of the aggressiveness of the offenses these teams have played moreso than the defenses themselves, and vice versa. Let me know in the comments section below if any of this data jumps out at you or if it prompts a deeper data dive.

FEI Degree of Difficulty through Week 8

FEI Degree of Difficulty (DOD) ratings are based on current FEI ratings, but instead of measuring efficiency against schedule, DOD measures record against schedule. What is the likelihood that an elite team (two standard deviations better than average) would play a given team's schedule to date and achieve that team's record?

My hypothesis is that the College Football Playoff selection committee is likely to value and reward something akin to DOD through their process and deliberations. As of this week, the following teams have the best records relative to the schedule each has faced to date. Each team's current FEI rating and remaining strength of schedule (RSOS) rating are also provided.

FEI Degree of Difficulty through Week 8
Rk Team W-L DOD FEI Rk RSOS Rk
1 LSU 7-0 .409 .253 5 .271 12
2 Michigan State 8-0 .476 .197 14 .443 35
3 Clemson 6-0 .488 .333 1 .807 82
4 Iowa 6-0 .570 .206 11 .789 76
5 Memphis 6-0 .676 .184 15 .580 48
6 Notre Dame 6-1 .685 .256 3 .284 13
7 Oklahoma State 6-0 .715 .167 19 .410 31
8 Utah 6-1 .734 .202 12 .748 69
9 Florida 6-1 .757 .207 10 .815 86
10 Alabama 7-1 .766 .256 4 .405 29

FEI 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. Unadjusted game efficiency (GE) is a measure of net success on non-garbage possessions, and opponent adjustments are calculated with special emphasis placed on quality performances against good teams, win or lose. Other definitions:

  • SOS: Strength of Schedule, measured as the likelihood of an elite team going undefeated against the given team's regular season schedule. Schedule strength data based on FEI ratings and calculated across other dimensions can be explored in this interactive visualization.
  • FBS MW: Mean Wins, the average number of games a team with the given FEI rating would be expected to win against its regular season schedule of FBS opponents.
  • FBS RMW: Remaining Mean Wins, the average number of games a team with the given FEI rating would be expected to win against the remainder of its regular season schedule of FBS opponents.
  • OFEI: Opponent-adjusted Offensive Efficiency value generated per possession.
  • DFEI: Opponent-adjusted Defensive Efficiency value generated per opponent possession.
  • STE: Special Teams Efficiency value generated per game possession.
  • FVE: Field Value Efficiency value generated per game possession.

Preseason projection data receives no weight in this week's ratings. Ratings for all FBS teams can be found here.

Rk Team FBS
Rec
FEI LW GE Rk SOS Rk FBS
MW
FBS
RMW
OFEI Rk DFEI Rk STE Rk FVE Rk
1 Clemson 6-0 .333 1 .272 3 .394 85 10.6 4.9 .70 14 1.15 3 .00 70 -.02 77
2 Stanford 6-1 .263 8 .267 5 .195 41 10.5 4.4 1.38 3 .01 63 .12 5 .16 12
3 Notre Dame 6-1 .256 6 .179 17 .040 1 9.6 3.9 1.16 6 .43 29 .06 29 .11 26
4 Alabama 7-1 .256 3 .205 11 .143 27 9.1 2.2 .47 27 1.22 1 -.07 103 .12 20
5 LSU 7-0 .253 4 .216 9 .111 22 9.0 2.8 1.04 7 .59 22 -.03 87 .00 69
6 Oklahoma 6-1 .232 7 .216 10 .180 37 10.2 3.9 .53 23 .96 4 -.04 93 .06 39
7 Michigan 5-2 .225 9 .244 7 .230 52 10.2 4.4 -.07 69 1.20 2 .17 3 .15 17
8 USC 4-3 .216 22 .202 12 .101 15 9.3 4.3 1.22 4 .37 32 .01 63 .08 36
9 Ohio State 8-0 .208 12 .267 4 .288 63 10.4 2.9 .54 21 .79 11 .06 28 .23 2
10 Florida 6-1 .207 11 .148 26 .211 46 9.9 4.4 .28 39 .76 12 -.02 83 .19 4
11 Iowa 6-0 .206 13 .169 21 .450 97 9.6 4.5 .26 40 .59 20 .05 34 .07 37
12 Utah 6-1 .202 2 .137 30 .220 51 9.6 4.3 .43 29 .74 13 .07 21 .11 23
13 Baylor 6-0 .201 5 .376 1 .279 61 9.1 3.4 1.67 2 .30 38 .02 52 .02 60
14 Michigan State 8-0 .197 14 .151 25 .211 47 9.9 3.0 .93 11 .42 30 -.14 121 .01 61
15 Memphis 6-0 .184 19 .131 31 .392 84 9.1 4.0 .65 16 -.03 67 .10 11 .06 40
Rk Team FBS
Rec
FEI LW GE Rk SOS Rk FBS
MW
FBS
RMW
OFEI Rk DFEI Rk STE Rk FVE Rk
16 Mississippi State 5-2 .182 24 .144 28 .167 33 8.0 2.7 .59 18 .69 17 .08 19 .08 35
17 Texas A&M 5-2 .175 15 .100 36 .131 25 7.8 2.9 -.10 72 .88 7 .13 4 .06 41
18 Tennessee 2-4 .174 20 .032 52 .110 21 7.9 4.5 .56 20 .33 35 .05 35 .13 19
19 Oklahoma State 6-0 .167 17 .200 14 .293 65 8.3 3.2 .23 42 .51 25 .10 10 .16 11
20 TCU 6-0 .162 18 .176 18 .217 50 8.2 2.8 .96 10 -.19 82 -.02 84 .09 32
21 Mississippi 5-2 .143 33 .117 32 .052 4 6.1 2.1 .40 31 .39 31 .00 74 -.03 78
22 North Carolina 4-1 .134 23 .202 13 .478 98 7.6 3.3 .59 19 -.09 75 .09 16 .01 62
23 Pittsburgh 5-1 .133 27 .072 42 .207 45 7.2 3.0 .05 60 .14 48 .06 30 .17 8
24 UCLA 5-2 .132 40 .101 35 .106 19 8.0 3.1 .43 30 .30 40 .06 27 .06 42
25 California 4-2 .128 10 .023 55 .078 10 6.3 2.9 .34 36 .13 50 -.05 96 -.01 71
26 Florida State 6-1 .122 21 .182 16 .099 14 7.6 1.9 .80 13 .19 46 -.01 76 .00 70
27 Houston 6-0 .122 28 .312 2 .563 108 8.9 3.5 .65 15 .34 34 -.02 82 .15 15
28 Washington 2-4 .120 16 -.025 72 .107 20 6.5 3.5 -.32 85 .80 10 .07 24 .02 53
29 Duke 5-1 .119 36 .108 34 .518 102 8.3 3.5 -.25 81 .32 36 .18 2 .23 1
30 Navy 4-1 .116 25 .165 23 .187 40 7.9 4.2 .85 12 .07 57 .00 71 -.11 105

Posted by: Brian Fremeau on 27 Oct 2015

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