Round Robin Tournament Scheduling
Schedules - You must register to Post and Download => Requests => Topic started by: Mattwoody on October 03, 2022, 09:36:37 AM
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Hi Everyone,
What i am looking for is a 12 person round robin
it is for a dart roster. we will be playing a double round robin. there is 4 dart boards
what i am looking to do is, have 3 groups of 4 each week. A vs B, C scores. C vs B, A scores, A vs C, B scores
I have worked it out for 9 player previously but for the life of me i am having trouble working it out for 12 people
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If you have been looking for a 6 round schedule where every pair of players oppose at least once, then I am sorry to say that this is impossible - it is a mathematically proven fact. It is possible to come close, a 6 round schedule exists (not shown) where only one pair of players does not meet - perhaps you found this already?
For the general problem with 3 players per board, some numbers of players like 9 and 15 work perfectly while others like 12 and 18 do not. I have put the smallest schedule for 12 players below where all pairs oppose at least once. Here the 1st round is short, only requiring one board.
(1 2 3) ( - - -) (- - -) (- - -)
(2 5 10) ( 7 4 11) (6 3 8) (1 9 12)
(3 6 11) ( 8 5 12) (4 1 9) (2 7 10)
(1 4 12) ( 9 6 10) (5 2 7) (3 8 11)
(6 12 7) (11 1 10) (8 2 9) (5 3 4)
(4 10 8) (12 2 11) (9 3 7) (6 1 5)
(5 11 9) (10 3 12) (7 1 8) (4 2 6)
Clearly, players 1 to 3 have one more match than the others, and as a consequence have 3 repeated opponents each, while players 4 to 12 only have one repeated opponent each. When you use the schedules you may choose not to play these repeated matches and give the players a bye.
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Oh, I am being stupid, I didn't see that you had said double round-robin in your post. This makes things much easier. For example :
Round Board A B C
1 1 7 6 3
1 2 4 1 8
1 3 11 10 12
1 4 2 5 9
2 1 4 12 3
2 2 10 8 2
2 3 9 11 6
2 4 1 5 7
3 1 3 5 6
3 2 12 2 1
3 3 10 9 4
3 4 8 11 7
4 1 8 4 5
4 2 2 6 7
4 3 9 3 12
4 4 1 10 11
5 1 7 10 5
5 2 6 12 1
5 3 8 2 9
5 4 11 4 3
6 1 11 8 6
6 2 10 1 3
6 3 5 12 2
6 4 9 7 4
7 1 3 8 5
7 2 12 10 7
7 3 6 4 2
7 4 1 9 11
8 1 5 6 10
8 2 8 9 12
8 3 7 4 1
8 4 3 2 11
9 1 4 2 10
9 2 6 1 8
9 3 7 3 9
9 4 5 11 12
10 1 3 8 10
10 2 9 1 5
10 3 6 12 4
10 4 2 7 11
11 1 2 3 1
11 2 12 7 8
11 3 11 5 4
11 4 10 6 9