This might not be the question that's on everyone's mind as the college football season heads into the home stretch, but it's an interesting one to consider from a statistics viewpoint.
Most people wouldn't know offhand but would guess that Stanford—who is 7-1, ranked #13 in the BCS, and just blew out Washington 41-0—is probably better at rushing defense than MAC member Kent State, who stands at 4-4.
Look at the NCAA's stats, however, and you may be surprised. Not because Stanford is only #40, but because Kent State has only given up a paltry 65.9 yards per game, good enough to rank as the #1 team in college football in that area.
So it's settled: #40 Stanford vs. #1 Kent State, the Golden Flashes win, right? Not so fast. When we look at who they've played, and the rushing offenses of those teams, the picture changes again.
Stanford's I-A opponents, and their raw rushing offense rankings, have been:
- UCLA (#26, 193 ypg)
- Wake Forest (#33, 180)
- Notre Dame (#99, 113)
- Oregon (#3, 309)
- USC (#21, 201)
- Washington State (#117, 73)
- Washington (#73, 144)
Stanford's opponents average 173 yards per game on the ground, which would rank at #40 in the nation. The Cardinal are giving up an average (not counting I-AA Sacramento State) of 144 yards per game which isn't fantastic, but against above-average competition their rushing defense is re-evaluated upwards to some extent. And this is just one iteration; the above teams' rushing offenses can be compared to their opponents' defenses in the same way, and the process continued until the values settle and the dust clears. At that point, Stanford's rushing defense ranks #22 in the nation rather than #40.
Kent State, on the other hand, faces a comparatively weaker schedule:
- Boston College (#100, 111 ypg)
- Penn State (#84, 136)
- Miami Ohio (#119, 63)
- Akron (#106, 105)
- Toledo (#71, 146)
- Bowling Green (#120, 62)
- Ball State (#47, 160)
Immediately you can see why Kent State is #1 in raw rushing defense. Their opponents include the bottom two team in the country (Bowling Green and Miami of Ohio) in rushing offense. Even the BCS conference teams they played—Boston College and Penn State—are far below average in this stat. The top rushing offense the Golden Flashes have faced is 2-7 Ball State's. Combined, these teams average just 112 yards per game, which would rank an individual team at #100 on the raw list.
So Kent State's #1 ranking is an illusion. It's not that they aren't good, as they've held these teams to an average of about 85 yards per game, far less than the teams' aggregate average. But when corrected for their schedule, Kent State ranks #21, not #1. Their raw average is helped by an opening contest against Murray State, whom they held to -65 yards (in college, sacks count as rushing yards).
These adjusted rankings can be found on SportsRatings' adjusted Rushing Defense stats page, and now I'm including the raw rankings right next to the adjusted rankings so it's easy to compare. For those too lazy to click, here's an excerpt:
Raw Adj Team Rec Total[rank] Rush[rank] Pass[rank]
5 1. Iowa 6-2 286.2[ 10] 51.6[ 1] 234.5[ 81]
3 2. Boston College 3-5 290.9[ 11] 74.1[ 2] 216.8[ 62]
11 3. South Carolina 6-2 324.8[ 29] 74.8[ 3] 250.0[103]
6 4. Arizona 7-1 308.8[ 21] 76.8[ 4] 231.9[ 78]
4 5. Ohio State 8-1 252.2[ 3] 78.9[ 5] 173.3[ 13]
21 6. Mississippi St 7-2 300.0[ 15] 84.0[ 6] 215.9[ 58]
2 7. Boise St 7-0 257.9[ 4] 87.4[ 7] 170.4[ 12]
7 8. Pittsburgh 5-3 283.6[ 9] 92.6[ 8] 190.9[ 32]
16 9. Arizona St 4-4 338.7[ 38] 98.3[ 9] 240.4[ 92]
9 10. TCU 9-0 222.3[ 1] 104.0[ 10] 118.2[ 1]
37 11. LSU 7-1 273.6[ 6] 105.8[ 11] 167.8[ 11]
24 12. Auburn 9-0 323.0[ 28] 106.4[ 12] 216.6[ 60]
28 13. Syracuse 6-2 307.4[ 19] 108.2[ 13] 199.2[ 44]
10 14. West Virginia 5-3 309.2[ 22] 109.8[ 14] 199.3[ 45]
30 15. Michigan St 8-1 334.9[ 35] 111.5[ 15] 223.3[ 71]
27 16. Texas 4-4 233.2[ 2] 112.0[ 16] 121.2[ 3]
8 17. Texas A&M 5-3 294.0[ 12] 114.7[ 17] 179.2[ 16]
31 18. California 4-4 282.5[ 8] 115.4[ 18] 167.1[ 10]
18 19. Georgia 4-5 301.2[ 17] 115.8[ 19] 185.4[ 22]
26 20. Illinois 5-3 296.6[ 13] 116.3[ 20] 180.2[ 17]
1 21. Kent St 4-4 365.7[ 55] 116.6[ 21] 249.1[100]
40 22. Stanford 7-1 312.7[ 25] 117.9[ 22] 194.7[ 38]
So now we can answer the question: who has a better rushing defense, Stanford or Kent State? and right now the winner is Kent State, by one position, #21 to #22. Realistically the answer is "it's too close to call" but if we had to pick one or the other, Kent State it is. But instead of having 38 teams in between them, they are side-by-side. Kent State leads by a nose. The figures suggest that against an average I-A team on a neutral field, Kent State would give up 116.6 yards and Stanford 117.9 on the ground.
Iowa, the #5 team in raw numbers, actually has the top rush rushing defense in the country by a decent margin. Like Kent State, Boise State also drops when schedule is considered, from #2 to #7. Texas A&M, who has played mainly pass-happy teams, is overrated at #8 raw, falling to #17 in the corrected figures.
Other teams that move up when schedule is considered include SEC teams South Carolina, Mississippi State, LSU, and Auburn, reflecting the great rushing offenses in that league. Georgia, however, remains roughly the same, probably due to the fact that they've played enough pass-oriented team (Arkansas, Colorado, Louisiana Lafayette, Kentucky) that their raw average is pretty accurate to start with.
There is also our Yards-Per-Carry Rushing Defense listing, which takes things down to a per-carry basis rather than per-game. These are figured a bit differently but also correct for opposition. In that list, Kent State is #14 and Stanford #24, more evidence that the Golden Flashes really are a bit better than the Cardinal in ground defense, but still a lot closer than raw per-game numbers would suggest.
Great stats, love this! Keep up the good work1
Posted by: djk | December 07, 2010 at 12:33 AM
Have you done stats for 2011 yet? This is great!
Posted by: Ray Cambridge | November 11, 2011 at 04:16 PM