The View From Wisconsin

Methodology
Win Strength Rating is a (mostly) simple way of expressing the relative "strength" of a NCAA football team's win total in a given season. Win Strength Rating (WSR) begins with a team's win totals, expressed in three areas - overall wins, conference wins, and expected wins. Expected Wins are figured based on the team's points scored and allowed over a given season, using the Pythagorean Theorem posited by Bill James way back in the 1980's. All three of these win totals are averaged together to produce the raw Win Strength score.

In an effort to account for schedule strength, each team's raw score is adjusted based on their SOS rating in four of the computer ranking systems (Anderson, Colley, Massey and Sagarin). It's arbitrary, of course, since those four are the only ones that provide strength of schedule totals in their ranking lists. To determine the WSR strength of schedule component, first you determine the average SOS rating in each of the four ranking systems for all of Division I-FBS. In 2008, these totals were: Anderson, .495; Colley, .498667; Massey, 3.581; and Sagarin, 69.51.

Next, each individual team's SOS rating is divided by the subdivision's average for each of the four rankings, producing a number that is either greater than 1 (indicating a team whose schedule was stronger than the average team), or less than 1 (indicating a team whose schedule was weaker than the average team). These four "percentages" are averaged together to produce the Strength of Schedule factor. For example, Utah's SOS Average for 2008 was 0.99558 - just slightly less than the average Division I-FBS team (and the worst SOSA in the top 10). Utah's Win Strength Rating, before the Sugar Bowl, was only 9.92 (compared to their actual total of 12 wins).

For bowl games, however, the regular season WSR is adjusted because of the increased schedule strength of their opponents. The 68 teams playing in the 34 scheduled bowl games had an average SOSA of 1.015779. So, to adjust for the difference, teams that win their bowl game have their WSR increased by 1.015779, while the losers have it decreased by the same amount. Obviously, the base WSR will be adjusted by the extra win in the standings and the additional points scored and allowed, so WSR can vary from the end of the regular season to the last bowl game. Utah's WSR was bumped up to 11.528 by their win over 'Bama in the Sugar Bowl - which, at the time, moved them into third behind USC and Florida.

USC and Texas temporarily held the top spot in WSR before the BCS title game; however, it was already unlikely that whoever won the BCS Championship would end up not finishing ahead of the Trojans in the final standings. Florida was ranked third going into the BCS title game and Oklahoma fifth; both were also less than one "win" away from the Longhorn's WSR of 12.492 and USC's 12.085.

Listed below is the top 10 in WSR:
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RK Team ------ CONF GP -W-L- PCT PF-PA -- XW% |CW-L |BW-L | -WSR- SOSA
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1. Florida --- SECE 14 13 1 .929 611 181 .919 | 7-1 | 1-0 | 13.26 1.117
2. Texas ----- B12S 13 12 1 .923 551 244 .836 | 7-1 | 1-0 | 12.49 1.153
3. USC ------- PA10 13 12 1 .923 488 117 .946 | 8-1 | 1-0 | 12.08 1.028
4. Utah ------ MTWC 13 13 0 .999 480 224 .821 | 8-0 | 1-0 | 11.53 0.996
5. TCU ------- MTWC 13 11 2 .846 437 147 .898 | 7-1 | 1-0 | 10.95 1.005
6. Oklahoma -- B12S 14 12 2 .857 716 343 .813 | 7-1 | 0-1 | 10.64 1.151
7. Missouri -- B12N 14 10 4 .714 591 381 .706 | 5-3 | 1-0 | 10.12 1.098
8. Va.Tech --- ACCC 14 10 4 .714 309 234 .636 | 5-3 | 1-0 | 09.98 1.126
9. Georgia --- SECE 13 10 3 .769 409 319 .622 | 6-2 | 1-0 | 09.94 1.112
10. Alabama -- SECW 14 12 2 .857 422 200 .817 | 8-0 | 0-1 | 09.84 1.036
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Incidentally, the worst team in Division I-FBS was the University of Washington, who failed to win a single game this year. Their 1.12292 SOS average did not help their cause, as they finished with a 0.474 WSR. North Texas was next to last with a WSR of 0.806; that total was primarily due to their very weak Sun Belt Conference schedule (a SOS average of .86308).