[computer-go] CGOS pairings using Christoph Birk formula

[Christoph Birk]

On Mon, 16 Oct 2006, Don Dailey wrote:
> What I have decided on, based on several different simulations,  is the
> following:
>   1.  Fix N at 3
>   2.  Pick one unpaired player P at random.
>   3.  Loop 3 times doing the following:
>   4.     Select a potential unpaired opponent R as a candidate opponent
>          for P,  randomly.  Opponent R must not also be P.
>   5.     Compare the rating difference of the current selection to the
>          best selection found so far.
>   6.     If the difference is smaller, R is new best candidate.
>   7.  Repeat whole procedure until all players are paired.

I like it ... it's simple.
The pairing-probability table (NP=14) looks like:
        2    3    4    5    6    7    8    9   10   11   12   13   14
01:  3.5  2.2  1.6  1.2  0.9  0.7  0.5  0.5  0.4  0.4  0.4  0.3  0.4
02:       2.5  1.7  1.2  0.9  0.7  0.5  0.4  0.4  0.3  0.3  0.3  0.3
03:            2.3  1.5  1.1  0.8  0.6  0.4  0.4  0.3  0.3  0.3  0.3
04:                 2.1  1.4  0.9  0.7  0.5  0.4  0.3  0.3  0.3  0.4
05:                      2.0  1.4  1.0  0.6  0.4  0.4  0.4  0.4  0.4
06:                           1.9  1.4  0.9  0.6  0.5  0.4  0.4  0.5
07:                                1.9  1.4  1.0  0.7  0.6  0.5  0.5
08:                                     2.0  1.4  1.0  0.8  0.7  0.7
09:                                          2.0  1.4  1.0  0.9  0.9
10:                                               2.1  1.5  1.2  1.2
11:                                                    2.3  1.7  1.6
12:                                                         2.5  2.2
13:                                                              3.5

Christoph