Round Robin 2v2 Tournament (11 Participants, 2 courts)

[MCC23]

Hello!

I'm organizing a 2v2 tournament with 11 participants but I'm stuck trying to figure out how to get each player to play WITH and AGAINST each other player at least once..

Ideally, every participant would play at least a total of 10 matches.

Any help would be greatly appreciated!

Thanks in advance!

[Ian Wakeling]

There is no good solution for 11 people playing doubles - the problem is that a total of 10 matches each is not a whole number of doubles games.  The following 14 round schedule is a possibility for 11 people A to K:

[(D J):(B K)] [    A:F    ]
[(A H):(C J)] [(E G):(B I)]
[(H K):(B F)] [(G I):(A C)]
[(A J):(D G)] [(F K):(E I)]
[(C K):(D I)] [(F H):(B G)]
[(F I):(D H)] [(B E):(C G)]
[(E H):(A D)] [(C I):(F J)]
[(G H):(C D)] [(A E):(J K)]
[(B H):(A I)] [(C E):(D F)]
[(B C):(A K)] [(G J):(E F)]
[(C H):(E K)] [(I J):(B D)]
[(C F):(B J)] [(A G):(I K)]
[(H I):(E J)] [(F G):(D K)]
[(D E):(A B)] [(G K):(H J)]

The pair (A F) do not meet apart from in the singles game, for the other players they all partner once and oppose twice.

[MCC23]

Hello Ian,

This is actually really good and would've been perfect except for the fact that I have 2 last minute cancellations.
Bringing our total number of participants to 9.

Do you have a similar schedule but for 9 players?

And follow up question: how do you even start with creating a schedule like this?
Do you do it by heart or is there a method of generating similar schedules?

Either way, thanks for your response!

Kind regards,

[Ian Wakeling]

9 players is a lot easier as there is a standard schedule for this in 9 rounds, mathematicians call this a Whist Tournament Design (see example schedule below). The 11 player schedule above came from a computer program that I wrote myself - basically it assigns the partner pairs randomly to the schedule, then swaps pairs around to improve the schedule's balance.

9 players A to I, playing 9 rounds of doubles.

[(E G):(F C)] [(H B):(A D)]
[(C D):(G A)] [(I H):(E F)]
[(B G):(F H)] [(D I):(C E)]
[(H D):(G I)] [(F B):(A C)]
[(I E):(A B)] [(F D):(H C)]
[(A F):(D E)] [(C G):(B I)]
[(B C):(E H)] [(G F):(I A)]
[(C I):(H A)] [(B E):(D G)]
[(I F):(D B)] [(E A):(G H)]

[MCC23]

thanks so much for your help! Our tourney yesterday was a succes! <3