Round Robin Tournament Scheduling

12 Team, 6 events ??? any ideas?

Lucky69 · 13 · 11658

Lucky69

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on: March 30, 2008, 12:40:05 PM
I have a tournament going on with 12 teams and 6 events.  Not everyone has to play eachother


Lucky69

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Reply #1 on: March 30, 2008, 01:44:01 PM
I also need every team to play in each event only once


McWolf

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Reply #2 on: March 30, 2008, 04:08:04 PM
label teams A - L,
events 1-6


  A B C D E F G H I J K L
A . 1 3 5 . . . . . 6 4 2
B . . 2 3 6 . . . . . 5 4
C . . . 1 4 5 . . . . . 6
D . . . . 2 4 6 . . . . .
E . . . . . 1 3 5 . . . .
F . . . . . . 2 3 6 . . .
G . . . . . . . 1 4 5 . .
H . . . . . . . . 2 4 6 .
I . . . . . . . . . 1 3 5
J . . . . . . . . . . 2 3
K . . . . . . . . . . . 1
L . . . . . . . . . . . .


So in your first event, A pays B, C plays D, E plays F...
In the second event, B plays C, D plays E, ..., A plays L.

Following this kind of schedule, you can have up to 11 events (number of teams minus 1), but you need to have an even number of teams (which you do, so it's not a problem).


Lucky69

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Reply #3 on: March 30, 2008, 09:28:04 PM
Only 2 teams can play in an event per round so does this diagram still work?


Lucky69

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Reply #4 on: March 30, 2008, 09:37:36 PM
The setup will kinda look like this...
              Foosball    -    Darts   -   Air Hockey    -    Ping Pong    -    Bowling    -    Pool
Round 1
Round 2    
Round 3
Round 4
Round 5
Round 6


Richard A. DeVenezias

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Reply #5 on: March 30, 2008, 10:05:41 PM
Quote
I have a tournament going on with 12 teams and 6 events.  Not everyone has to play each other

Here one way.
Split the 12 teams into two groups.  Over the course of playing the 6 events, have each team in the first group (1-6) play each team in the second group (7-12).

Each row is an event.  The six columns are the match ups for the event.

 1, 7    2, 8    3, 9    4,10    5,11    6,12
 1, 8    2, 9    3,10    4,11    5,12    6, 7
 1, 9    2,10    3,11    4,12    5, 7    6, 8
 1,10    2,11    3,12    4, 7    5, 8    6, 9
 1,11    2,12    3, 7    4, 8    5, 9    6,10
 1,12    2, 7    3, 8    4, 9    5,10    6,11
The Administrator.


Lucky69

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Reply #6 on: March 31, 2008, 01:52:50 PM
Sorry to keep bothering you but it still doesn't work...I have to rearrange the matchups so that only two teams can play in the 1 event each round


McWolf

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Reply #7 on: March 31, 2008, 08:28:17 PM
Sorry I misinterpreted what you meant by "event".

If you look in my omegathon thread I am also looking for a solution to this same type of problem. The schedule I gave you is part of the work that I have done but I haven't figured out a scheduling system yet. I'll put some more thought into it tomorrow when I'm done with my assignments, unless someone already has an answer for us.


Ian Wakeling

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Reply #8 on: April 01, 2008, 03:20:23 AM
I think the following schedule will work.

(A G) (B H) (C I) (D L) (E K) (F J)
(B C) (J G) (D E) (H I) (F A) (L K)
(K J) (C D) (G H) (E F) (I L) (A B)
(E L) (F K) (A J) (B G) (C H) (D I)
(F I) (A L) (B K) (C J) (D G) (E H)
(D H) (E I) (F L) (A K) (B J) (C G)


because of the symmetry, it doesn't matter which way around the rows and columns are assigned to rounds and events.  Mathematically this is known as a Howell Design.


Kikker

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Reply #9 on: April 21, 2008, 08:00:19 AM
This is exactly what I am looking for, but with 16 teams and 8 events.
Is there a schedule for too?

Thanks in advance!


Ian Wakeling

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Reply #10 on: April 22, 2008, 03:26:50 AM
Here is a special schedule for an all-plays-all round robin with the property that rounds 1 to 8, or alternatively rounds 8 to 15, considered separately are both solutions to your 8 event problem.

rnd   E1    E2    E3    E4   E5    E6    E7    E8
  1 (A N) (G D) (H J) (B L) (K P) (C M) (I O) (E F)
  2 (E O) (C K) (A P) (F I) (L J) (N B) (M D) (G H)
  3 (P B) (F O) (G C) (M E) (D A) (K H) (N L) (I J)
  4 (M J) (N P) (D B) (C H) (E I) (G O) (F A) (K L)
  5 (I C) (A H) (O L) (D P) (B F) (J E) (G K) (M N)
  6 (L G) (M I) (K E) (J A) (N C) (D F) (B H) (O P)
  7 (F H) (J B) (N I) (K O) (G M) (A L) (P E) (C D)
  8 (D K) (E L) (F M) (N G) (H O) (I P) (C J) (A B)
  9 (J P) (O A) (E H) (I K) (M B) (L C) (D N) (F G)
 10 (N E) (P F) (L D) (A C) (J G) (M K) (O B) (H I)
 11 (O M) (B C) (P G) (H D) (F N) (E A) (L I) (J K)
 12 (G A) (K N) (C O) (E B) (I D) (F J) (H P) (L M)
 13 (H L) (D J) (I A) (P M) (C E) (B G) (K F) (N O)
 14 (B I) (H M) (J N) (L F) (A K) (O D) (E G) (P C)
 15 (C F) (I G) (B K) (O J) (P L) (H N) (A M) (D E)


wed

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Reply #11 on: April 22, 2008, 02:20:58 PM
We take groups of 8, 12, 16 and 20 for golfing vacations of varying number of rounds (5, 6, 7, & 8) of golf .  In Dec 05 George Nigriny(Guest) wrote that he may have a formula that could provide pairings for our groups that would have everyone playing everyone else an eqaul or close to equal amount of rounds together.

  Do you know if he ever provided that formula or is there a way I can reach him to discuss it.


wed

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Reply #12 on: April 22, 2008, 02:27:53 PM
I just posted a message but I see no evidence that I posted a message.  I cannot send a message to the site adminstrator because the system says I have less than 1 posting!  How do I see any response to a posting?  Is it required to stay on line or is ther an email prompt that there is a message