A players and B players

[xman15]

I have a tourrnament with 8 A players and 8 B players.
In each round, each of the four games teams an A player with a B player vs. an A player and B player.
I would like to minimize the number of times you play with or against the same players, with 7 or 8 rounds.

[Ian Wakeling]

This is a similar problem to that of a mixed doubles competition.  There are standard schedules called spouse avoiding mixed doubles tournaments where you parnter and oppose everyone except your spouse exactly once.

(H1 W4 v H2 W7) (H3 W1 v H4 W5) (H5 W3 v H6 W8) (H7 W6 v H8 W2)
(H1 W7 v H3 W6) (H2 W5 v H7 W3) (H4 W2 v H5 W8) (H6 W1 v H8 W4)
(H1 W6 v H4 W8) (H2 W4 v H8 W5) (H3 W7 v H5 W2) (H6 W3 v H7 W1)
(H1 W3 v H5 W4) (H2 W8 v H6 W7) (H3 W5 v H8 W6) (H4 W1 v H7 W2)
(H1 W5 v H6 W2) (H2 W1 v H3 W8) (H4 W3 v H8 W7) (H5 W6 v H7 W4)
(H1 W8 v H7 W5) (H2 W3 v H4 W6) (H3 W2 v H6 W4) (H5 W7 v H8 W1)
(H1 W2 v H8 W3) (H2 W6 v H5 W1) (H3 W4 v H7 W8) (H4 W7 v H6 W5)

So I think the above gives you an option for 7 rounds of play, and you could play something like:

(H1 W1 v H2 W2) (H3 W3 v H4 W4) (H5 W5 v H6 W6) (H7 W7 v H8 W8)

if you wanted an eighth round.

[schedulecc]

This is almost perfect for my mixed doubles scenario, but is there a schedule that does 8 rounds on four courts that does have everyone pair with and play against all players (no spouse avoidance)?

[schedulecc]

Sorry, ignore the request.  I had mis-entered the schedule, it is perfect for 8 rounds.  This site is AWESOME, thank you so much!!

[dwfortner]

Hey, did you ever come up with an 8-week schedule for the mixed doubles that is not spouse avoiding?
I found a table for 16 players (8 women 8 men) in the paper Ian Co-wrote about generalizing the Spouse avoiding and strict mitchell mixed doubles round robin.
It shows a table for strict Mitchell Mixed Doubles Round Robin (strict MMDRR( 8 ) ), which has been really helpful, but I would love to know if someone worked through what an 8-round schedule of those matches would look like, with all players playing each round, if that's even possible.

[Ian Wakeling]

Hi, thanks for looking at the paper.  My best guess is that the schedule you want does not exist.  What I know is that the construction shown in the paper for larger schedules of 20, 24, 28,... players does not work for 16, and I have tried without any success to find a 16 player schedule by computer search. It is possible to have 16 players in 11 rounds on 3 courts (example 2.11), but of course there will be people with byes in every round.