reverse coed doubles random draw schedules

[tdfi2003]

I found your site and schedules quite helpful.  Do you have any suggestions to how to use some of the Whist formulas or other to set up a reverse coed  random draw volleyball tournament?  The number of players will be variable, but there will be equal number of men and women (say 8, 9, 10, ....).  There will be multiple nets, depending upon how many sign up.  Tomorrow we will have 10 men and 10 women, and 4 nets.  You won't play with or against everyone, but I want to minimize the number of times you play against someone.  Also, if 2 pairs are on one net, another two pairs will be on the 2nd net, and yet another 2 pairs on the 3rd net.  We might have 4 nets.  So if you're playing in the first round on one net, you can't be assigned to play that round on any other net.  I set this up with men having numeric values (e.g., 1, 2, 3...) and women alpha (A, B, C, ...).  It's hard enough to set up unique pairs with minimum number of times against another opponent (recall its a draw, where you play with someone different each game), but it starts to get really messy trying to set it up so a player does not show up more than once in each round (with 3 or 4 simultaneous games).
Thanks

Tim

[Ian Wakeling]

Tim,

Whist designs may not be the best starting point for you and it may be better to look at spouse avoiding mixed doubles schedules instead.  There is some relevant information on the latter here and also in the two links that you will find there.  Unfortunately a full spouse avoiding schedule for 10 pairs of men and women does not exist, so I don't think I can help with an off the shelf solution for your event. However if you had 9 pairs you could use the following schedule:

     Net 1           Net 2           Net 3           Net 4        Bye          
(H2 W7 v H3 W4) (H4 W2 v H7 W3) (H5 W8 v H9 W6) (H6 W5 v H8 W9) (H1 W1)
(H1 W5 v H3 W8) (H4 W6 v H9 W7) (H5 W3 v H8 W1) (H6 W9 v H7 W4) (H2 W2)
(H1 W9 v H2 W6) (H4 W7 v H8 W5) (H5 W4 v H7 W8) (H6 W1 v H9 W2) (H3 W3)
(H1 W6 v H7 W5) (H2 W3 v H9 W8) (H3 W9 v H8 W2) (H5 W1 v H6 W7) (H4 W4)
(H1 W7 v H9 W3) (H2 W4 v H8 W6) (H3 W1 v H7 W9) (H4 W8 v H6 W2) (H5 W5)
(H1 W2 v H8 W7) (H2 W8 v H7 W1) (H3 W5 v H9 W4) (H4 W3 v H5 W9) (H6 W6)
(H1 W8 v H4 W9) (H2 W5 v H6 W3) (H3 W2 v H5 W6) (H8 W4 v H9 W1) (H7 W7)
(H1 W3 v H6 W4) (H2 W9 v H5 W7) (H3 W6 v H4 W1) (H7 W2 v H9 W5) (H8 W8)
(H1 W4 v H5 W2) (H2 W1 v H4 W5) (H3 W7 v H6 W8) (H7 W6 v H8 W3) (H9 W9)

Here the men are H1 to H9, and the women W1-W9.  The spouse pairs H1 W1, H2 W2, etc.. never occur either as partners or as opponents, which is a feature of the schedule that you can ignore. What is important is that the schedule gives you upto 8 rounds of play (plus one bye) per player where all partners and all opponents are different.

Ian.

[tdfi2003]

Wow, this is great Ian!   In fact, we ended up with only 9 pairs.  My friend literally dreamt up a scheme that worked OK.  He had 3 nets with 3 pairs each; started off with each guy playing against each guy, but only with 2 of the women and one of the guys against a woman twice - so each round you played twice, reffed once; then split the net (3 pairs had not played, so one stayed on one net, the other two went to the other 2 nets).  Then reset the pairings as in round 1; and did it for one more round.  He started late so only went 3 rounds.  Men played against 6 different men, with 6 different women, and against 5 different women and vice versa.  It wasn't perfect but not bad in a pinch.  I'll definately hang on to the format you sent, as I prefer unique pairings (I also like the "spouse avoidance" term - cute, my wife would like that).
regards
Tim