> Can you say a few more words about the Colley
> Matrix? What is it? What
> does it do? Are there any references you might
> suggest for further
> information? Thanks and cheers!
>
> - Pat
>

The Colley Matrix is one of the components of
the BCS system. It is designed and run by Wesly N. Colley and is printed in
the Atlanta
Journal and Constitution.

It is from the Just Win Baby (JWB) school of thought and does not factor in
margin of victory
(MOV). It also does not factor in home field advantage or most recent games.
Everyone starts the year off equal.

What it does do is control for the strength of each individual opponent the
team has played.
The elegant part about it is that once the data are in order it calculates the
rankings without having to iterate the way maximum likelihood or nonlinear
least squares would. All it requires is inverting a matrix and muliplying it
by a vector. That's the beauty of it.

The other great thing about this system is that the author tells you exactly
how he does it. There are no hidden fudge factors. I hate it when people
refuse to divulge how they do it.



You can find out more about it at his web site including an example.
http://www.colleyrankings.com/




Correction - Excel is supposed to do an inverse of a matrix but I couldn't get
minverse to work right. It kept giving me a scalar (single value) instead of
a matrix. I ended up having to run the matrix part of the example in SAS.

Alan