THE POWER RANK

3 predictions from a new college football ranking system, week 6, 2013.

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Rankings based on a regression model designed for early in the season.

Rankings based on a regression model designed for early in the season.

After 5 weeks of the college football season, we’re still in the dark about most college football teams. The only certainty is that Lane Kiffin no longer coaches USC.

I always try to improve the preseason and early season college football rankings at The Power Rank. The primary rankings on the site still use last season’s games, with this season’s games counted twice. I think they do a good job, but this method reacts slowly to teams that have struggled, such as Texas (31st).

So I developed new model this week. It’s based on the regression model that I used for my preseason predictions, which consider a team’s rating the last 4 years, turnovers and returning starters. Now, the model includes a rating calculated from only games this year.

The visuals shows the top 10 teams in this regression model. While Baylor is mostly likely overrated at 2nd since they have not played anyone, I do like that Alabama has dropped to 3rd and Washington has cracked the top 10.

Let’s look at the predictions this model makes.

How low should Texas be ranked?

Texas checks in at 51st in this regression model. Their moderate success over the past 4 seasons (moderate by Texas standards) and a host of returning starters keep the Longhorns above the average FBS team (125 teams total).

For last night’s game at Iowa State, the regression model predicted a 2.3 win for Iowa State. The rankings that use last year’s games had Texas by 2.8. The regression model has reacted faster to the Longhorn’s struggles, who have lost badly to Mississippi and BYU.

Texas squeaked out a win last night over Iowa State. They needed a hail mary touchdown at the end of the 1st half as well as a no call on a fumble that would have ended Texas’s game winning drive. Further more, Iowa State gained 6.0 yards per play compared to 4.9 for Texas.

Mack Brown is dating Lady Luck.

How good are the predictions of the new model?

I went back and tested how accurately each ranking system predicted game winners. This test considered all games after week 5 from the 2007 to 2012 seasons.

The regression model predicted 69.2% of game winners, while The Power Rank using last year’s games got 68.9% correct. With an error of about 0.8%, both rankings system have the same predictive power.

However, both methods perform better than The Power Rank with only this year’s games. Those rankings predicted 67.5% of game winners, quite a bit less.

Let’s look at the predictions these two models make.

Notre Dame and Arizona State

Notre Dame has disappointed this season. They have already lost twice, and that 7 point win over Purdue looks worse as the Boilermakers continue to lose badly each week.

The rankings with last year’s games predict a 1.3 point loss against Arizona State at a neutral site in Dallas. However, the regression model predicts a 5.5 point loss, the same as the line.

I still don’t know what to think about Notre Dame. Their defense doesn’t tackle well in the secondary. But Oklahoma scored 14 points off of 2 tipped passes against the Fighting Irish last week. Moreover, QB Tommy Rees had a terrible game.

I’d stay away from this game.

Illinois at Nebraska

Illinois has been a pleasant surprise, a rarity in the Big Ten this season. Behind the 9th best offense, the Fighting Illini are 53rd in the regression model, a miracle for a team that finished 115th last season.

They travel to Lincoln to face a Nebraska team that has struggled on defense. The regression model has reacted more quickly to the opposite fortunes of these two teams, picking a 6 point win for Nebraska (the line favors Nebraska by 9).

The rankings with last year’s games have Nebraska by 13.6 points. With the two teams that do not resemble their preseason expectations, it’s safe to ignore this prediction.

This is my upset special for the week. Nebraska’s offense has not lived up to expectations, and QB Taylor Martinez will not play again this week. Illinois gets the win in Lincoln. Next week’s headlines give Mack Brown a week of reprieve and focus on the job security of Bo Pellini.

Kansas State at Oklahoma State

Kansas State lost a host of starters from last season’s stellar team. In addition, the Wildcats had an unsustainable turnover margin in 2012. Hence, my preseason ranking had them at 37th.

The rankings with last season’s games predict a tight game (0.8 points) in favor of Oklahoma State. Again, it’s safe to ignore that given the changes to this Kansas State team.

The regression model predicts a 9 point win for Oklahoma State. This margin is probably to big. Kansas State fumbled the ball 3 times in gifting a win to Texas last week.

The line favors Oklahoma State by 14. This is too much for a team whose offense hasn’t performed at the elite level it did last season.

What do you think?

I’ve copied the rankings from the regression model below. Would you like to see them as the primary rankings?

Let me know in the comments. Thanks for reading.

1. Oregon (4-0), 28.80
2. Baylor (3-0), 26.81
3. Alabama (4-0), 23.22
4. Stanford (4-0), 17.67
5. Georgia (3-1), 15.98
6. Texas A&M (4-1), 15.55
7. LSU (4-1), 15.49
8. Washington (4-0), 14.31
9. Florida State (4-0), 14.14
10. Florida (3-1), 14.07
11. Ohio State (5-0), 13.87
12. Clemson (4-0), 13.46
13. Louisville (4-0), 12.92
14. UCLA (4-0), 12.58
15. Wisconsin (3-2), 11.93
16. South Carolina (3-1), 11.47
17. Miami (FL) (4-0), 10.73
18. TCU (2-2), 10.14
19. Oklahoma (4-0), 10.14
20. Arizona State (3-1), 9.84
21. Texas Tech (4-0), 9.74
22. Arizona (3-1), 9.59
23. Missouri (4-0), 9.01
24. Utah State (3-2), 8.32
25. Mississippi (3-1), 8.17
26. USC (3-2), 7.75
27. Northwestern (4-0), 7.42
28. Oklahoma State (3-1), 7.41
29. Oregon State (4-1), 7.23
30. Northern Illinois (4-0), 5.76
31. Virginia Tech (4-1), 5.24
32. Tennessee (3-2), 4.79
33. Maryland (4-0), 4.72
34. Auburn (3-1), 4.67
35. UCF (3-1), 4.53
36. Penn State (3-1), 4.43
37. Notre Dame (3-2), 4.37
38. Boise State (3-2), 4.28
39. Nebraska (3-1), 4.11
40. Iowa (4-1), 3.92
41. Michigan State (3-1), 3.67
42. Utah (3-2), 3.45
43. Brigham Young (2-2), 3.41
44. Vanderbilt (3-2), 3.05
45. Georgia Tech (3-1), 3.01
46. Michigan (4-0), 2.60
47. Fresno State (4-0), 2.24
48. West Virginia (3-2), 1.88
49. Arkansas (3-2), 1.76
50. Syracuse (2-2), 1.50
51. Texas (3-2), 1.40
52. Kansas State (2-2), 1.21
53. Illinois (3-1), 1.02
54. East Carolina (3-1), 0.94
55. Mississippi State (2-2), 0.80
56. North Carolina State (3-1), 0.73
57. Iowa State (1-3), 0.72
58. Washington State (3-2), 0.50
59. Rutgers (3-1), -0.15
60. Toledo (2-3), -0.17
61. Ball State (4-1), -0.23
62. Cincinnati (3-1), -0.33
63. San Jose State (1-3), -0.38
64. Pittsburgh (3-1), -0.44
65. Houston (4-0), -0.58
66. California (1-3), -0.62
67. North Carolina (1-3), -0.66
68. Kentucky (1-3), -0.75
69. Minnesota (4-1), -1.11
70. Bowling Green (4-1), -1.49
71. Marshall (2-2), -1.65
72. North Texas (2-2), -1.87
73. Indiana (2-2), -1.90
74. Boston College (2-2), -1.92
75. Western Kentucky (4-2), -2.02
76. Buffalo (2-2), -2.33
77. Ohio (3-1), -2.50
78. Rice (2-2), -2.77
79. Navy (2-1), -3.03
80. San Diego State (1-3), -3.31
81. Connecticut (0-4), -3.37
82. Colorado State (2-3), -4.02
83. Virginia (2-2), -4.74
84. Wyoming (3-2), -5.16
85. SMU (1-3), -5.28
86. Arkansas State (2-3), -5.78
87. Louisiana Lafayette (2-2), -6.11
88. Tulsa (1-3), -6.14
89. Nevada (3-2), -6.31
90. Duke (3-2), -6.34
91. Louisiana Monroe (2-4), -6.46
92. Colorado (2-1), -6.49
93. Army (2-3), -7.09
94. Wake Forest (2-3), -8.01
95. Temple (0-4), -8.05
96. Kent State (2-3), -8.11
97. Louisiana Tech (1-4), -8.17
98. Florida Atlantic (1-4), -8.54
99. Middle Tennessee State (3-2), -8.61
100. Purdue (1-4), -9.07
101. Kansas (2-1), -9.54
102. South Florida (0-4), -9.68
103. Tulane (3-2), -10.27
104. Western Michigan (0-5), -10.40
105. Troy (2-3), -11.14
106. UAB (1-3), -11.34
107. Hawaii (0-4), -11.75
108. Air Force (1-4), -11.80
109. UNLV (3-2), -12.39
110. Southern Miss (0-4), -13.19
111. Memphis (1-2), -13.20
112. Akron (1-4), -13.27
113. UTEP (1-3), -14.38
114. Idaho (1-4), -14.94
115. Miami (OH) (0-4), -15.71
116. Florida International (0-4), -15.86
117. Central Michigan (1-4), -16.30
118. Eastern Michigan (1-3), -17.36
119. New Mexico (1-3), -18.10
120. New Mexico State (0-5), -19.98

Will The SEC Still Make The BCS Title Game?

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When Alabama lost to Texas A&M this weekend, it left no undefeated SEC teams. In response, my friend Chris Haddock, a family practice doctor and raging Georgia Bulldogs fan, posted this on Facebook:

UGA has one win against a BCS Top 10 opponent. Florida has three. Alabama has two. Comined Kansas State, Oregon, Notre Dame have ZERO. Nada. Zilch. If the SEC Championship Game winner doesn’t play for the national championship then it is a tainted title to whichever of these undeserving non-SEC teams wins.

Since the SEC has won the last 6 national championships, many will share this sentiment.

And our numbers agree. Alabama only dropped to 2nd behind Oregon in our rankings, and 6 of the top 10 teams come from the SEC. With this many good teams in a conference, you expect every team to lose at least once.

The question becomes whether the SEC champion, either Alabama or 7th ranked Georgia, makes the BCS title game. For this to happen, two of these 3 teams must lose.

Oregon.

  • Team rank: 1st.
  • Probability of remaining undefeated: 58.7%.
  • Toughest remaining game: 76.3% chance to beat Oregon State.

Kansas State.

  • Team rank: 3rd.
  • Probability of remaining undefeated: 64%.
  • Toughest remaining game: 80% chance to beat Texas.

Notre Dame.

  • Team rank: 8th.
  • Probability of remaining undefeated: 41.4%.
  • Toughest remaining game: 44% chance to beat USC.

Somehow, I don’t think I’ll be able to publish Chris’s next post if Notre Dame squeaks past USC and into the national title game ahead of the SEC champion.

Last week, Alper Akanser, a Ph.D. student at Georgia Tech, took our undefeated probabilities and determined the chance that 0, 1, 2… teams would remain undefeated. This week, his code gives a 42.7% chance that 0 or 1 teams remain undefeated, opening the door for the SEC champion.

That’s pretty good odds for the SEC.

How Likely is BCS Chaos?

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Earlier this week, we calculated that Alabama, Kansas State, Oregon and Notre Dame had a 6.7% chance to all remain undefeated. Alper Akanser, a member of The Power Rank, went one step further. Using our probability for each team to remain undefeated, he calculated the likelihood that any number of teams remain undefeated.

  • 0 of 4 teams remain undefeated: 5.4%.
  • 1 of 4 teams remain undefeated: 23.5%.
  • 2 of 4 teams remain undefeated: 38.0%.
  • 3 of 4 teams remain undefeated: 26.4%.
  • 4 of 4 teams remain undefeated: 6.7%.

For those of us keen to inflict extra embarrassment upon the lame duck BCS system, there’s a 33.1% chance that at least 3 of these teams remain undefeated.

Thanks, Alper. We appreciate others doing work for us 🙂

14 Reasons The Top 4 BCS Teams Won’t All Remain Undefeated

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The Playoff PAC made this trophy for those undefeated teams that do not play in the National Championship game.

If Alabama, Kansas State, Oregon and Notre Dame remain undefeated, there will be some angry college football fan in early December. The antiquated BCS can pick only 2 teams for its championship game. The four team playoff that will grace this sport in 2014 can’t come soon enough.

However, the likelihood that all 4 teams remain undefeated is small. To understand why, assume these teams have a 80% chance to win each of their remaining games. The 80% reflects the dominance of these teams, and the uniform win probability makes the math simple. Including the conference championship games, these teams have 14 games remaining. The probability that they all remain undefeated is 0.8 to the 14th power, or 4.4%.

Not very likely.

What Retirement Says About College Football

To understand why this probability is so small, consider a retirement account. If this investment returns 10% annually, then $10,000 becomes $11,000 next year but compounds to $174,494 in 30 years. In the opposite way, the chance these teams remain undefeated decreases rapidly with the number of remaining games. Your mathematician friends call this an exponential decrease. The 14 remaining games are the reasons we won’t likely see four undefeated teams at season’s end.

Again, the 80% win probability is a uniform number that simplifies the math in showing the exponential decrease. On the field, Alabama has a higher likelihood (81.1%) of beating Texas A&M on Saturday. With the more realistic win probabilities of The Power Rank, there is a 6.7% chance these 4 teams remain undefeated. This includes an Alabama versus Georgia SEC championship game. Also, it assumes UCLA, the most likely team to win the Pac-12 South, travels to Oregon for the Pac-12 championship game.

Detailed Breakdown of the Four Teams.

Here’s a more detailed breakdown of the remaining defeated teams. The team rank come from our college football rankings. The offense and defense rankings results from adjusting yards per play for strength of schedule.

Alabama. Either the Crimson Tide pass defense had an off night against LSU or Zack Mettenberger became Andrew Luck overnight. The former is more likely.

  • Team rank: 1st.
  • Probability of remaining undefeated: 58.7%.
  • Toughest remaining game: 75.6% chance to beat Georgia.
  • Offense rank: 1st.
  • Defense rank: 2nd.

Kansas State. While Colin Klein’s arm motion isn’t pretty, he is leading the 4th best pass offense according to our numbers.

  • Team rank: 3rd.
  • Probability of remaining undefeated: 57.1%.
  • Toughest remaining game: 82.2% chance to beat TCU.
  • Offense rank: 7th.
  • Defense rank: 30th.

Oregon. Can a team slow down Oregon’s rushing attack enough to make freshman quarterback Marcus Mariota beat them? While Stanford has the 3rd best rush defense, the Ducks have made them look silly the past two years.

  • Team rank: 2nd.
  • Probability of remaining undefeated: 48.2%.
  • Toughest remaining game: 72.4% chance to beat Oregon State.
  • Offense rank: 6th.
  • Defense rank: 13th.

Notre Dame. The Fighting Irish were 5th in our rankings before their near death experience at home against Pitt.

  • Team rank: 9th.
  • Probability of remaining undefeated: 41.6%.
  • Toughest remaining game: 49.7% chance to beat USC.
  • Offense rank: 23rd.
  • Defense rank: 11th.

What do you think?

Will these teams all remain undefeated? Who will go down first? Please leave us a comment.

Thanks for reading.