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(Message started by: The_Jeh on Oct 17^th, 2007, 5:52pm)

Title: College Football
Post by The_Jeh on Oct 17^th, 2007, 5:52pm

Just for fun, I decided to create my own computer model for ranking sports teams, especially college football. I spent an unhealthy amount of time entering the results of hundreds of games, and the top 25 results are as follows:

Through Week 7
1. South Florida 6-0
2. Ohio State 7-0
3. LSU 6-1
4. Boston College 7-0
5. Arizona State 7-0
6. Kentucky 6-1
7. Kansas 6-0
8. Missouri 6-1
9. Oregon 5-1
10. South Carolina 6-1
11. Oklahoma 6-1
12. Virginia Tech 6-1
13. Hawaii 7-0
14. Cincinnati 6-1
15. Virginia 6-1
16. West Virginia 5-1
17. Auburn 5-2
18. California 5-1
19. Boise State 5-1
20. Texas Tech 6-1
21. Kansas State 4-2
22. Illinois 5-2
23. Connecticut 5-1
24. Tennessee 4-2
25. Florida 4-2

Where's USC? Umm... #35. I'm not sure whether that's accurate, but, objectively, my system isn't impressed with USC's loss to Stanford. To be honest, even without the loss, USC's rank only jumps to #11. I can't decide whether that supports or discredits my amateurish model.

Title: Re: College Football
Post by Fritzlein on Oct 17^th, 2007, 7:11pm

Did you get the data from Peter Wolfe? http://prwolfe.bol.ucla.edu/cfootball/scores.htm
It should be possible to ingest the results automatically every week, to save the tedious data entry. If you intend on doing this regularly, definitely inform Kenneth Massey of your intention, so you can see how your rankings correlate with all the other computer rankings. http://www.masseyratings.com/cf/compare.htm

It is interesting to me that computer rankings tend to put LSU nearer the top than the AP poll and other polls. One of the traditional criticisms of polls is that undefeated teams are rewarded beyond their desserts (i.e. without proper consideration of strength of schedule) and it looks like this difference is being borne out again this season.

The further the season progresses, the more I trust computer rankings, and the less I trust the human polls.

Title: Re: College Football
Post by Fritzlein on Oct 17^th, 2007, 8:22pm

I see on Massey's site that the consensus computer ranking for USC is #22, but that one rating system (the RPI) has them all the way down at #59, so I don't think it invalidates your methods by any means that USC is at #35.

Title: Re: College Football
Post by The_Jeh on Oct 18^th, 2007, 12:11am

Thanks for the links. They're gold.

I do not wish to lose all credibility, but admittedly, I am not talented enough to convert Wolfe's excellent table into something useful to me. Suffice it to say, I have an "inexplicable" desire to do things the hard way, but it won't be that bad now that I can enter one week's worth at a time.

I don't know if Massey needs me, but I'll definitely post my top 25 here each Sunday or Monday, and we'll see how well it callibrates itself.

Title: Re: College Football
Post by mistre on Oct 18^th, 2007, 8:10am

And people say that USF is over-ranked, and you have them at #1!

I live in Tampa, FL and work at USF and as you can imagine there is alot of buzz going on about the season they are having. They play a tough Rutgers team tonight, so let's see if they can stay undefeated.

Nice work on your rankings system - looks pretty good to me.

Title: Re: College Football
Post by The_Jeh on Oct 18^th, 2007, 10:50pm

South Florida loses 27-30. I'm really sorry. To be honest, I hoped they would take it all the way undefeated - a team that has only been around for 11 years and reached #2 the first year it was ever ranked.

With that one game added, USF drops to #5 in my ranking. Rutgers rises to #22. A few other teams also change places. However, don't count on this staying this way after I enter the games that are to take place this weekend.

Title: Re: College Football
Post by mistre on Oct 19^th, 2007, 8:36am

I think they fall further than #5 - I am guessing somewhere between 10 and 15.

After other teams play this weekend, your ranking might reflect the same.

Title: Re: College Football
Post by The_Jeh on Oct 21^st, 2007, 6:27pm

Through Week 8, with previous rank in parentheses:

1. Ohio State 8-0 (2)
2. LSU 7-1 (3)
3. Boston College 7-0 (4)
4. South Florida 6-1 (1)
5. Arizona State 7-0 (5)
6. Missouri 6-1 (8)
7. Oregon 6-1 (9)
8. Kansas 7-0 (7)
9. Virginia 7-1 (15)
10. Virginia Tech 6-1 (12)
11. Oklahoma 7-1 (11)
12. Connecticut 6-1 (23)
13. Hawaii 7-0 (13)
14. Florida 5-2 (25)
15. Boise State 6-1 (19)
16. Kentucky 6-2 (6)
17. West Virginia 6-1 (16)
18. Michigan 6-2 (NR)
19. Texas A&M 6-2 (NR)
20. South Carolina 6-2 (10)
21. Alabama 6-2 (NR)
22. Rutgers 5-2 (NR)
23. Georgia 5-2 (NR)
24. Wake Forest 5-2 (NR)
25. Auburn 5-3 (17)

Dropped: Cincinnati 6-2 (14), California 5-2 (18), Texas Tech 6-2 (20), Kansas State 4-3 (21), Illinois 5-3 (22), Tennessee 4-3 (24)

I see no problem with South Florida only dropping to #4, as now Rutgers is ranked. I disagree with including Texas A&M.

When I count the number of games I should have included, I always come up with two fewer than the number of games my program says I've entered. I've checked and checked, but I cannot find the two phantom games. However, I don't think they would affect the rankings. I've gone over each team's W-L record, and everything looks to be in order. I really have no idea where the two games are coming from.

Title: Re: College Football
Post by Fritzlein on Oct 21^st, 2007, 11:38pm

One thing that sticks out is ranking Missouri #6. That's much higher than either the human polls or other computer rankings.

Title: Re: College Football
Post by The_Jeh on Oct 22^nd, 2007, 8:07am

Well, their only loss is to Oklahoma, ranked #4 by the AP and USA Today. And on the Massey tables, Burdorf gives Missouri #1. I might be inclined to agree with you, but I think they could be underrated, too.

Title: Re: College Football
Post by The_Jeh on Oct 23^rd, 2007, 1:05am

Okay, I'm going to let the cat out of the bag and admit that I've been bluffing all along. What I said was a computer model was really just what Massey would call an "Ad hoc calculator feasible formula system." Here's how simple these rankings have been:

For each game a team wins, its performance score (PS) increases by (1+opponent's total wins)/(1+opponent's total games). For each game a team loses, its PS decreases by (1+opponent's total losses)/(1+opponent's total games). A team's rating is then (1+PS/(games played)).

I am amazed that this simple formula produced such good results. However, I recognize how much it leaves to be desired. Therefore, lest you think I am incapable of producing a true computer ranking, I've created what Massey would call an "advanced computer system," one that "Repeatedly recalculate[s] the ratings until they stabilize." This time, I have discovered a way to convert Peter Wolfe's list into a useful format, so the results through week 8 incorporate 719 teams and 2643 games.

Title: Re: College Football
Post by The_Jeh on Oct 23^rd, 2007, 1:24am

Allow me to introduce the new and improved rating system. After the W-L record appears the team's rating and schedule strength, respectively.

1. Boston College 7-0 216.665 / 116.665
2. LSU 7-1 211.369 / 136.369
3. South Florida 6-1 204.647 / 133.218
4. Ohio State 8-0 196.599 / 96.599
5. Virginia 7-1 191.800 / 116.800
6. Arizona State 7-0 189.143 / 89.143
7. Oregon 6-1 185.307 / 113.878
8. Virginia Tech 6-1 182.010 / 110.582
9. Kentucky 6-2 179.862 / 129.862
10. Florida 5-2 178.882 / 135.965
11. Missouri 6-1 174.969 / 103.541
12. South Carolina 6-2 173.500 / 123.500
13. Wake Forest 5-2 172.206 / 129.348
14. West Virginia 6-1 171.175 / 99.746
15. Auburn 5-3 167.872 / 142.872
16. Michigan 6-2 167.685 / 117.685
17. Kansas 7-0 163.805 / 63.805
18. Connecticut 6-1 161.037 / 89.608
19. Georgia 5-2 160.165 / 117.308
20. UCLA 5-2 159.713 / 116.856
21. Oklahoma 7-1 157.132 / 82.132
22. Rutgers 5-2 156.872 / 114.015
23. Alabama 6-2 155.808 / 105.808
24. Texas A&M 6-2 148.503 / 98.503
25. USC 6-1 148.238 / 76.809

Title: Re: College Football
Post by The_Jeh on Oct 28^th, 2007, 8:52pm

Through Week 9

1. Boston College 8-0 (1)
2. LSU 7-1 (2)
3. Arizona State 8-0 (6)
4. Ohio State 9-0 (4)
5. Oregon 7-1 (7)
6. South Florida 6-2 (3)
7. Kansas 8-0 (17)
8. Virginia Tech 6-2 (8)
9. West Virginia 7-1 (14)
10. Georgia 6-2 (19)
11. Wake Forest 6-2 (13)
12. Connecticut 7-1 (18)
13. Michigan 7-2 (16)
14. Auburn 6-3 (15)
15. Clemson 6-2 (NR)
16. Virginia 7-2 (5)
17. Alabama 6-2 (23)
18. Missouri 7-1 (11)
19. Florida 5-3 (10)
20. Oklahoma 7-1 (21)
21. South Carolina 6-3 (12)
22. Tennessee (NR)
23. Kentucky 6-3 (9)
24. Purdue 7-2 (NR)
25. Georgia Tech 5-3 (NR)

Dropped: UCLA, Rutgers, Texas A&M, USC

Also, here are the top 25 I-A schools in terms of their schedule strength during the past nine weeks:

1. Notre Dame
2. North Carolina
3. Duke
4. North Carolina State
5. Washington
6. Florida
7. Auburn
8. Maryland
9. Mississippi
10. South Florida
11. Tennessee
12. LSU
13. Virginia Tech
14. Georgia
15. Stanford
16. Boston College
17. South Carolina
18. Mississippi State
19. Kentucky
20. Georgia Tech
21. Florida State
22. California
23. Colorado
24. Vanderbilt
25. Nebraska

Title: Re: College Football
Post by The_Jeh on Nov 4^th, 2007, 2:00pm

Through Week 10

1. LSU 8-1 (2)
2. Oregon 8-1 (5)
3. Boston College 8-1 (1)
4. Ohio State 10-0 (4)
5. Arizona State 8-1 (3)
6. Virginia Tech 7-2 (8)
7. Kansas 9-0 (7)
8. Missouri 8-1 (18)
9. Georgia 7-2 (10)
10. Connecticut 8-1 (12)
11. Virginia 8-2 (16)
12. Florida 6-3 (19)
13. Michigan 8-2 (13)
14. Oklahoma 8-1 (20)
15. West Virginia 7-1 (9)
16. Clemson 7-2 (15)
17. South Florida 6-3 (6)
18. Alabama 6-3 (17)
19. Florida State 6-3 (NR)
20. Kentucky 6-3 (23)
21. Auburn 7-3 (14)
22. Wake Forest 6-3 (13)
23. Penn State 7-3 (NR)
24. Texas 8-2 (NR)
25. Tennessee 6-3 (22)

Dropped: South Carolina (21), Purdue (24), Georgia Tech (25)

Title: Re: College Football
Post by The_Jeh on Nov 11^th, 2007, 3:29pm

Through Week 11

1. LSU 9-1
2. Oregon 8-1
3. Arizona State 9-1
4. Ohio State 10-1
5. Missouri 9-1
6. Georgia 8-2
7. Virginia Tech 8-2
8. Kansas 10-0
9. Boston College 8-2
10. Florida 7-3
11. West Virginia 8-1
12. Clemson 8-2
13. Virginia 9-2
14. Oklahoma 9-1
15. Kentucky 7-3
16. Connecticut 8-2
17. Illinois 8-3
18. South Florida 7-3
19. USC 8-2
20. Michigan 8-3
21. Tennessee 7-3
22. Texas 9-2
23. Wisconsin 8-3
24. Cincinnati 8-2
25. Penn State 8-3

And here's the list according to the second method, in which A/(A+B) is supposed to be the probability that team A defeats team B. One win and two losses to the anchor have been added:

1. Kansas 10-0 5.29894
2. LSU 9-1 5.06887
3. Ohio State 10-1 4.61614
4. Oregon 8-1 4.26414
5. Missouri 9-1 4.15172
6. Arizona State 9-1 3.86729
7. Oklahoma 9-1 3.76847
8. West Virginia 8-1 3.38880
9. Virginia Tech 8-2 3.18943
10. Georgia 8-2 3.16231
11. Hawai'i 9-0 3.08210
12. Boston College 8-2 3.00936
13. Clemson 8-2 2.90501
14. Virginia 9-2 2.80576
15. Florida 7-3 2.75881
16. Connecticut 8-2 2.69-72
17. Texas 9-2 2.68546
18. Illinois 8-3 2.67068
19. Michigan 8-3 2.53739
20. Cincinnati 8-2 2.51279
21. Boise State 9-1 2.46767
22. Wisconsin 8-2 2.39914
23. Kentucky 7-3 2.38191
24. South Florida 7-3 2.36844
25. USC 8-2 2.31010

Title: Re: College Football
Post by Fritzlein on Nov 11^th, 2007, 5:43pm

on 11/11/07 at 15:29:24, The_Jeh wrote:

Through Week 11

1. LSU 9-1
2. Oregon 8-1
3. Arizona State 9-1
4. Ohio State 10-1
5. Missouri 9-1
6. Georgia 8-2
7. Virginia Tech 8-2
8. Kansas 10-0

This first method shows how you can be penalized for playing weak opponents, even if you beat them. Kansas would be better off having not even played its first four games. Remove those wins, and then a 6-0 Kansas will top the list, or at least be very near.

Title: Re: College Football
Post by The_Jeh on Nov 11^th, 2007, 7:49pm

Yeah. The schedule strength system would be more meaningful if margin of victory were taken into consideration, because then there would be realistic expectations for playing weak teams. I really am not a big fan of margin of victory though, as I think the object of a game is to win, not win by any certain amount.

Title: Re: College Football
Post by The_Jeh on Nov 18^th, 2007, 12:18pm

Well then, for the new week I'm going to abandon the first method. When I think about the reasoning of the second method, I like it a lot better.

Remember, with this system, the likelihood that team A defeats team B is given by A/(A+B). All college football games have been considered. In addition, each team has been given one win and two losses to a fictional Anchor team. The computer then calculates what rating values maximize the likelihood of seeing the results that were seen.

Through November 17

1. Kansas 11-0 5.41899
2. LSU 10-1 5.20502
3. Ohio State 11-1 5.17529
4. Missouri 10-1 4.50428
5. West Virginia 9-1 3.99573
6. Arizona State 9-1 3.72979
7. Boston College 9-2 3.68082
8. Georgia 9-2 3.65684
9. Virginia Tech 9-2 3.43755
10. Hawai'i 10-0 3.35496
11. Florida 8-3 3.02305
12. Oregon 8-2 2.99427
13. Illinois 9-3 2.86958
14. Oklahoma 9-2 2.80531
15. Connecticut 9-2 2.74282
16. Virginia 9-2 2.71375
17. Texas 9-2 2.67379
18. South Florida 8-3 2.63219
19. Boise State 10-1 2.55841
20. Clemson 8-3 2.48578
21. Wisconsin 9-3 2.42086
22. Tennessee 8-3 2.37501
23. Brigham Young 8-2 2.35899
24. USC 8-2 2.32043
25. Cincinnati 8-3 2.24387

Predictions for selected games this week:
Kansas 55%, Missouri 45%
Hawai'i 57%, Boise State 43%
West Virginia 59%, Connecticut 41%
Arizona State 62%, USC 38%
LSU 79%, Arkansas 21%

Title: Re: College Football
Post by The_Jeh on Nov 25^th, 2007, 1:24am

Through November 24

1. Missouri 11-1 5.60693
2. Ohio State 11-1 5.06008
3. West Virginia 10-1 4.85715
4. Hawai'i 11-0 4.26141
5. Kansas 11-1 4.18928
6. Boston College 10-2 4.08614
7. Georgia 10-2 3.97843
8. Virginia Tech 10-2 3.95533
9. LSU 10-2 3.88606
10. Oklahoma 10-2 3.25863
11. Florida 9-3 3.24526
12. Arizona State 9-2 2.93417
13. Illinois 9-3 2.89044
14. Clemson 9-3 2.86987
15. South Florida 9-3 2.86491
16. Brigham Young 9-2 2.82428
17. Tennessee 9-3 2.74949
18. USC 9-2 2.72120
19. Wisconsin 9-3 2.42238
20. Oregon 8-3 2.33131
21. Connecticut 9-3 2.32555
22. Cincinnati 9-3 2.29049
23. Virginia 9-3 2.28968
24. Michigan 8-4 2.18822
25. Boise State 10-2 2.16534

Title: Re: College Football
Post by The_Jeh on Nov 29^th, 2007, 1:42pm

I have recently made huge improvements to the ranking system. I made a new model that considers only points and disregards wins and losses. When I combine it with the Bradley-Terry model (with anchor), the results are much better than any of my rankings before. It is much harder to tabulate, however, so here are the top ten teams using games through November 24:

1. West Virginia
2. Missouri
3. Ohio State
4. Kansas
5. Oklahoma
6. LSU
7. Florida
8. Georgia
9. Arizona State
10. Virginia Tech
[11. South Florida]
[12. Hawai'i]

Title: Re: College Football
Post by The_Jeh on Dec 2^nd, 2007, 10:41am

Final Rankings

1. Oklahoma 11-2
2. Ohio State 11-1
3. Kansas 11-1
4. LSU 11-2
5. Missouri 11-2
6. Florida 9-3
7. West Virginia 10-2
8. Virginia Tech 11-2
9. USC 10-2
10. Georgia 10-2
11. Arizona State 10-2
12. South Florida 9-3
13. Clemson 9-3
14. Cincinnati 9-3
15. Oregon 8-4
16. Boston College 10-3
17. Brigham Young 10-2
18. Texas 9-3
19. Tennessee 9-4
20. Illinois 9-3
21. Hawai'i 12-0
22. Boise State 10-2
23. Auburn 8-4
24. Arkansas 8-4
25. Penn State 8-4