SportsRatings: College Basketball

Power Ratings update: Texas, Vanderbilt jump

I'm going to write about the power ratings after Thursday games, opposite the post-Sunday writeups for my Top 25. Power ratings are updated twice weekly, following Sunday and Thursday games.

This week saw a move by Texas in the Win-Loss ratings, and Vanderbilt in the Points rating.

First the Win/Loss ratings:

#   Team                      rec      Rating   Pts rank
1.  Memphis                   24-0     48.84       3
2.  Duke                      22-1     45.14       2
3.  Tennessee                 22-2     30.38       6
4.  Texas                     20-4     28.89      19
5.  Kansas                    23-2     26.33       1
6.  UCLA                      21-3     24.71       5
7.  North Carolina            23-2     19.54       4
8.  Wisconsin                 20-4     17.26       8
9.  Drake                     22-2     16.77      27
10. Georgetown                20-3     16.47       7
11. Pittsburgh                19-5     16.01      21
12. Butler                    23-2     15.96      36
13. Michigan St.              20-4     15.79      25
14. Stanford                  20-4     15.66      12
15. Purdue                    20-5     14.04      45
 

Texas is up to #4 now following their win over Kansas. They also have wins over Tennessee and UCLA, meaning they've defeated 3 out of the top 5 teams other than themselves. This gives them an enormous amount of "win" points, and even though they have four losses, most are to good teams. The Jayhawks slip to one spot below Texas; they really don't have a whole lot of strength in terms of big wins. Much like North Carolina, their high poll rankings comes from the manner in which they win (and being a traditional power), rather than who they're beating.

Note how close Duke is getting to Memphis. This is interesting, since undefeated teams have the aggregate strength of their wins with no losses to mitigate it. Duke's win score is much higher than Memphis', so much so that they are nearly equal in overall score. Their one loss to Pitt doesn't diminish the total very much, and as the year goes on, the difference between one loss and none grows smaller. If both teams win out, Duke could potentially surpass the Tigers, though Memphis would have a win over Tennessee that might keep them ahead.

Other notes: Drake slips a bit following their second loss. Pittsburgh is up to #11 despite 5 losses, 2 of those to teams with non-winning records; their wins over Duke and Georgetown are outweighing those right now. In the Big Ten, Wisconsin's win over Indiana keeps them in the top ten, while Michigan State slides to #13 after losing to Purdue, who now sits at #15 and is clearly either overachieving or getting better each week.

Points-only power rating:

#   Team                      rec      Rating   W/L rank
1.  Kansas                    23-2     25.84       5
2.  Duke                      22-1     25.02       2
3.  Memphis                   24-0     23.17       1
4.  North Carolina            23-2     22.09       7
5.  UCLA                      21-3     21.98       6
6.  Tennessee                 22-2     20.69       3
7.  Georgetown                20-3     19.08      10
8.  Wisconsin                 20-4     18.87       8
9.  West Virginia             17-7     18.74      49
10. Xavier                    21-4     18.59      16
11. Marquette                 17-6     18.43      21
12. Stanford                  20-4     18.08      14
13. Louisville                19-6     17.90      23
14. Kansas St.                17-6     17.54      25
15. Texas A&M                 20-4     17.53      18

The Big East has several highly-rated teams that have too many losses to be included in the polls, but clearly show strength when they do win, or lose close games. West Virginia, of course, has had its share of bad luck, losing to Georgetown and to Pittsburgh on questionable calls. In a points-based system, these don't affect their rating significantly; losing by 1 or winning by 1 barely tilts their ranking. But looking at the W and L columns, these are significant setbacks.

Louisville and Kansas State are two teams with six losses that are probably much better than their records indicate. Especially Louisville, whose losses are generally to quality teams (BYU, Dayton, Purdue, and Connecticut all have 7 or fewer losses). Also, the Cardinals are an improved team since David Padgett returned on January 1st. Before that, Louisville ranked #41; since then, they've played like a top 5 team.

But the team of the week is Vanderbilt. On Tuesday they beat Kentucky 93-52, and while one game out of twenty-some doesn't normally affect the ratings very much, it's interesting to see what a blowout like this can do. Previous to Tuesday, Vanderbilt ranked #66 with a 9.80 rating (surprisingly low for a 20-4 team, but then their early schedule was soft). After the Kentucky game, they vaulted to #52 with a 11.07 rating. And Kentucky? They started just four spots behind the Commodores, at #70 with a 9.44 rating (suggesting an expected 4 point home win for Vandy). Now, they're #84 with a 7.79 score.

Power Ratings for games through 2/3/2008

Power rating updates for games through February 3, 2008.

Points-only power rating, top ten as of 2/3/2008:

#   Team                      rec      Rating   W/L rank
1.  Kansas                    21-1     26.71       3
2.  Duke                      19-1     25.33       2
3.  Memphis                   21-0     24.21       1
4.  North Carolina            21-1     24.21       5
5.  UCLA                      20-2     22.60       6
6.  Tennessee                 19-2     20.57       4
7.  Georgetown                18-2     20.48       9
8.  Wisconsin                 18-3     19.68      10
9.  Xavier                    18-4     19.63      18
10. West Virginia             16-6     18.82      46

Kansas remains #1 despite their loss. The biggest change is Wisconsin moving into the top ten while West Virginia falls from #7 to #10 after losing by 23 at home to Cincinnati.

Here is the current top ten in the Win/Loss ratings, where score doesn't matter:

#   Team                      rec      Rating   Pts rank
1.  Memphis                   21-0     46.30       3
2.  Duke                      19-1     32.03       2
3.  Kansas                    21-1     29.42       1
4.  Tennessee                 19-2     27.45       6
5.  North Carolina            21-1     25.27       4
6.  UCLA                      20-2     22.59       5
7.  Texas                     17-4     20.47      20
8.  Drake                     20-1     19.16      26
9.  Georgetown                18-2     17.75       7
10. Wisconsin                 18-3     16.33       8 

The Jayhawks' first loss drops them to #3, while former #6 Washington State tumbles out of the top ten after losing two games. Michigan State's loss to Penn State dumps them from the top ten as well; replacing them are Georgetown and Wisconsin, who beat Indiana last week. UCLA moves up from 9th to 6th after sweeping the Arizona teams.

The top six in this "rewards" ranking are a reordering of the "predictive" points-based system, as well as being the top six teams in the subjective SportsRatings Top 25. Right now these six teams are head and shoulders above the rest of the collegiate field.

College Basketball Power Ratings updates for 1/27/2008

Power rating updates for games through 1/27/2008. I'll be updating my power ratings twice weekly now, after games on Thursday (since Friday rarely has important games) and after Sunday's games (since that's when the polls come out and is the de facto "end of week" for college basketball).

Points-only power rating, top ten as of 1/27/2008:

#   Team                      rec      Rating   W/L rank
1.  Kansas                    20-0     28.01       2
2.  Duke                      17-1     25.43       3
3.  Memphis                   19-0     25.10       1
4.  North Carolina            19-1     24.25       5
5.  UCLA                      18-2     21.32       9
6.  Tennessee                 17-2     20.82       4
7.  West Virginia             15-5     20.67      45
8.  Xavier                    17-4     20.22      17
9.  Georgetown                16-2     19.96      11
10. Marquette                 14-4     18.90      16

Kansas is #1, as they were last week, several points ahead of #2 Duke and #3 Memphis. Notice the same three top the Win/Loss power rating, except in a different order. The consensus order would probably be Kansas, Memphis, Duke if I combined the ratings in some way.

The top six teams here are also top ten in the Win/Loss ratings. West Virginia is the sore thumb here; their game outcomes haven't lived up to their average quality of play. But some of their high rating is due to a couple of early blowouts: 106-41 over #335 Prairie View and 110-44 over #339 Maryland Eastern Shore. They did defeated Marquette by 15 and Syracuse by 20.

Here is the current top ten in the Win/Loss ratings, where score doesn't matter:

#   Team                      rec      Rating   Pts rank
1.  Memphis                   19-0     39.85       3
2.  Kansas                    20-0     37.49       1
3.  Duke                      17-1     27.79       2
4.  Tennessee                 17-2     25.15       6
5.  North Carolina            19-1     23.51       4
6.  Washington St.            17-2     23.28      13
7.  Texas                     16-3     20.47      14
8.  Michigan St.              18-2     18.83      17
9.  UCLA                      18-2     18.63       5
10. Drake                     18-1     18.32      23

Last week Kansas was #1 in both rating systems, but Memphis' win over Gonzaga gave them some extra points. Since neither team has a loss, their aggregate rating is the sum of their wins, and Memphis' wins over Georgetown and USC give them a slight advantage over the Jayhawks. Kansas' best wins are over Arizona and Oklahoma, and Memphis has defeated both those teams as well.

Still, both are well ahead of #3 Duke, since every team from then on has a loss. Tennessee has an impressive rating for a 2-loss team; they are currently #1 in the RPI rankings. #10 Drake rates only 23rd in the Points-only system, which is still quite respectable. Their schedule has not been very tough, but they are now one of only five teams remaining with one or fewer losses.

College Basketball Power Ratings - Points, Win/Loss

I've finally had time to start the two basic power ratings (Points and Win/Loss) for college basketball. I will be adding a few other varieties soon. But for now, here are the top 25 in each category.

Points power rating, through 1/16

#   Team                      rec      Rating
1.  Kansas                    17-0     27.27
2.  Duke                      14-1     25.85
3.  North Carolina            18-0     25.03
4.  Memphis                   16-0     24.37
5.  West Virginia             12-4     22.94
6.  Marquette                 13-2     22.38
7.  Tennessee                 14-1     22.27
8.  UCLA                      16-1     21.95
9.  Wisconsin                 14-2     20.83
10. Xavier                    14-4     19.93
11. Georgetown                13-2     19.43
12. Indiana                   14-1     18.64
13. Texas                     13-3     18.26
14. Pittsburgh                15-2     18.25
15. Washington St.            14-1     17.90
16. Gonzaga                   13-4     17.65
17. Texas A&M                 15-2     17.62
18. Stanford                  13-3     17.14
19. Duquesne                  11-4     16.94
20. Michigan St.              15-2     16.59
21. Notre Dame                13-3     16.58
22. Arizona                   11-5     16.11
23. Connecticut               11-4     16.04
24. Drake                     15-1     15.97
25. Clemson                   14-3     15.92

Not too many surprises there. A pretty high correlation with Sagarin's "Pure Points" and Pomeroy's ratings. Duquesne ranks a lot higher here than in Pomeroy's.

Win/Loss power rating through 1/16

#   Team                      rec      Rating
1.  North Carolina            18-0     34.69
2.  Tennessee                 14-1     27.81
3.  Duke                      14-1     25.21
4.  Kansas                    17-0     24.79
5.  Memphis                   16-0     23.79
6.  Pittsburgh                15-2     22.61
7.  Texas                     13-3     21.73
8.  UCLA                      16-1     20.80
9.  Washington St.            14-1     20.29
10. Marquette                 13-2     18.90
11. Wisconsin                 14-2     17.76
12. Butler                    16-1     16.14
13. Michigan St.              15-2     16.11
14. Dayton                    14-2     15.36
15. Mississippi               15-1     13.44
16. St. Mary's                14-2     13.35
17. Vanderbilt                16-1     13.05
18. Rhode Island              15-2     13.03
19. Drake                     15-1     12.94
20. Indiana                   14-1     11.05
21. Massachusetts             12-4     10.86
22. Villanova                 12-3      8.21
23. Xavier                    14-4      7.96
24. Stephen F. Austin         13-2      7.95
25. Oregon                    12-4      7.90

Considering only wins and losses, North Carolina is a firm #1. Tennessee, with only a loss to Texas (and an algorithm that doesn't care it was by 19 points), places 2nd, just ahead of Duke (who lost to Pitt in overtime). The two other undefeated teams follow at 4th and 5th.

Then, Pitt and Texas (the only teams to beat Duke and Tennessee) are 6th and 7th, with UCLA (loser to Texas) and Washington State (loser to UCLA) following in what makes a pretty logical order. Marquette is one place ahead of Wisconsin, whom they beat.