I have found an individual who has put a lot of effort into generating 2 vs. 2 pairings for bridge competitions that eliminates same partner pairing and minimizes repeat opponent pairings. He has made a lot of his results available for free on the internet (as long as you give him the credit). Here is a reply he sent to and e-mail of mine and a link to his web page:
The Chamberlain Bridge Problem
What do you think Nate?
james.l.meyer@gm.com wrote:
> Now to the issue, both competitions use a two vs. two tournament style
> where the matches are "randomly" generated, with some restrictions applied.
> ... The number
> of teams participating in OCCRA us usually in the range of 15 - 25, and for
> FIRST 45 - 100 and the number of matches is typically 5 to 11.
> matches are also set up so that every team plays a minimum number of
> matches (like 6) and as small a group as possible (1 - 3 teams) play one
> extra match.
(I like to use the word "rounds" for a collection of "matches".)
Here are some thoughts....
- My program is indeed well-suited to pick two vs two matches.
- My program will not understand the "extra match" part.
- My program is interruptible. It will continue to improve until
any of several conditions occur. A keyboard interrupt will
output the best solution found.
- My code is free. You can download, tweak, etc. The links to
the code might not work though, let me know. My brother has
run it with the Gnu compiler under Windows.
- With 5 rounds, more than 25 people should be easy, this will be
roughly scaleable up to say 11 rounds for 50 or more people.
> I believe all of our combinations of teams and matches would make it quite
> difficult to do the pairings ahead of time.
Actually, you can do the setups for 25-100 people ahead of time and
do something like N/5 rounds. These might be good enough to just
use the first set of rounds and ignore the extra. For the lower
numbers of people (or the higher numbers of rounds) it might be a
bit tougher to do ahead of time, because of the amount of time the
program takes.
> ... I've also thought about assigning a full set of
> partners (100 unique partner sets for 50 matches) and then focusing on who
> will compete against whom.
That seems like a different kind of competition, since learning
to cooperate with your partner would be a major factor. However,
I have done a version of my program which works exclusively on
"pairs". We have prepared charts for N teams playing N-1 rounds
for up to about N=40. They seem to get harder for larger N but
maybe playing N-2 or N-3 rounds would make it easier. Again, if
you have a perfect setup for 30 teams playing 29 rounds you can
just use the first 11 rounds or whatever.
--
Paul Chamberlain,
tif@tifster.com