Computer rating systems

[appzter]

Last year, I posted (http://www.dukebasketballreport.com/forums/showthread.php?t=7966) about my computer rating system that I use to fill out my bracket (or at least to choose which games to watch). Here (http://www.duke.edu/~mhj32/bball-09.txt) are the ratings for this year, and the following are the predicted results for all of the first-round matchups:


First Round:
1 Connecticut, 16 Chattanooga (23.67)
1 Louisville, 16 Morehead St. (18.14)
1 North Carolina, 16 Radford (22.96)
1 Pittsburgh, 16 East Tennessee St. (16.13)
2 Duke, 15 Binghamton (20.48)
2 Memphis, 15 Cal St. Northridge (15.47)
2 Michigan St., 15 Robert Morris (14.99)
2 Oklahoma, 15 Morgan St. (16.39)
3 Kansas, 14 North Dakota St. (7.68)
3 Missouri, 14 Cornell (13.26)
3 Syracuse, 14 Stephen F. Austin (12.32)
3 Villanova, 14 American (12.87)
4 Gonzaga, 13 Akron (14.68)
4 Wake Forest, 13 Cleveland St. (8.55)
4 Washington, 13 Mississippi St. (7.21)
4 Xavier, 13 Portland St. (9.01)
5 Florida St., 12 Wisconsin (-.09)
5 Illinois, 12 Western Kentucky (9.37)
5 Purdue, 12 Northern Iowa (9.24)
5 Utah, 12 Arizona (1.72)
6 Arizona St., 11 Temple (4.91)
6 Marquette, 11 Utah St. (5.22)
6 UCLA, 11 Virginia Commonwealth (7.91)
6 West Virginia, 11 Dayton (12.15)
7 Boston College, 10 Southern California (-3.41)
7 California, 10 Maryland (2.08)
7 Clemson, 10 Michigan (6.85)
7 Texas, 10 Minnesota (2.59)
8 Brigham Young, 9 Texas A&M (6.67)
8 Louisiana St., 9 Butler (-.01)
8 Ohio St., 9 Siena (2.55)
8 Oklahoma St., 9 Tennessee (-.62)

The number to the right is the expected margin of victory. A negative number means that the lower seed is expected to upset the higher seed.

The ratings also predict a Final Four of UNC, UConn, Pitt, and West Virginia.

What do you guys think?

- matt

[pamtar]

Looks very interesting but are we supposed to be able to follow the link (http://www.duke.edu/~mhj32/rankings.txt) on the old post?

[appzter]

The old rankings are at http://www.duke.edu/~mhj32/bball-08.txt.

[CMS2478]

The games that I still have blank in my first round are the 8/9 matchups. These always kill me in my brackets. Specifically, the BC/USC matchup. Right now I am leaning toward USC over BC, although I wouldn't mind seeing the ACC team win. What do you guys think?

[rtnorthrup]

Can you give us some explanation of how the computer ratings work? How do these number differ from Pomeroy?

[mgtr]

Good info, but I would be surprised if Wisconsin beat FSU.

[A-Tex Devil]

Good info, but I would be surprised if Wisconsin beat FSU.

Me too, but almost every computer model I've seen has Wiscy ahead of FSU. Will be curious to see how it plays out.

[appzter]

Can you give us some explanation of how the computer ratings work? How do these number differ from Pomeroy?

The game data is fitted into a linear system with slight weights and score caps and solved by least squares. Pomeroy used to employ a similar method but dropped it in favor of Pythagorean winning percentage, which basically estimates winning percentage based on points for and points against. Interestingly, the two unrelated methods produce pretty similar results (e.g., both systems rank WVU and Gonzaga significantly higher than human polls).