Welcome, Guest. Please Login or Register.
Round Robin Tournament Scheduling
03/27/17 at 10:33:48
News: Up and running!
Home Help Search Login Register

Hello, and welcome to this Round Robin Tournament Scheduling community. more... Hosted by Richard A. DeVenezia

Learn more about round robin schedules, or look at some schedules.
Note: If your account has been removed in error, please use the contact link at devenezia.com

1  Schedules / Requests / Re: 12 round, 3 on 3 Round Robin with random teams
 on: Today at 03:47:32 
Started by johnz1 | Post by Ian Wakeling
John,
 
Thanks for the interesting question.  Certainly I can make a 16 round schedule where there are 12 games played each.   For example:

  ( 1  3 11 v 10 14 13) ( 7  9 16 v  5  4 15)   ( 2 12  6  8)
  ( 2  4 12 v 11 15 14) ( 8 10  1 v  6  5 16)   ( 3 13  7  9)
  ( 3  5 13 v 12 16 15) ( 9 11  2 v  7  6  1)   ( 4 14  8 10)
  ( 4  6 14 v 13  1 16) (10 12  3 v  8  7  2)   ( 5 15  9 11)
  ( 5  7 15 v 14  2  1) (11 13  4 v  9  8  3)   ( 6 16 10 12)
  ( 6  8 16 v 15  3  2) (12 14  5 v 10  9  4)   ( 7  1 11 13)
  ( 7  9  1 v 16  4  3) (13 15  6 v 11 10  5)   ( 8  2 12 14)
  ( 8 10  2 v  1  5  4) (14 16  7 v 12 11  6)   ( 9  3 13 15)
  ( 9 11  3 v  2  6  5) (15  1  8 v 13 12  7)   (10  4 14 16)
  (10 12  4 v  3  7  6) (16  2  9 v 14 13  8)   (11  5 15  1)
  (11 13  5 v  4  8  7) ( 1  3 10 v 15 14  9)   (12  6 16  2)
  (12 14  6 v  5  9  8) ( 2  4 11 v 16 15 10)   (13  7  1  3)
  (13 15  7 v  6 10  9) ( 3  5 12 v  1 16 11)   (14  8  2  4)
  (14 16  8 v  7 11 10) ( 4  6 13 v  2  1 12)   (15  9  3  5)
  (15  1  9 v  8 12 11) ( 5  7 14 v  3  2 13)   (16 10  4  6)
  (16  2 10 v  9 13 12) ( 6  8 15 v  4  3 14)   ( 1 11  5  7)

 
Above all pairs of players are together in the same group of 6 exactly 4 times, pairs that partner only once oppose 3 times, while pairs that partner twice, oppose twice.  So this should be optimal for 16 rounds.
 
It is theoretically possible to have a perfect 20 round schedule where there are 15 games played each - all partners twice and all opponents three times.   Unfortunately I have not been able to find this yet, but if I do, I will post it here.
Reply Quote Notify of replies  

2  Schedules / Requests / Re: 12 round, 3 on 3 Round Robin with random teams
 on: Yesterday at 15:40:42 
Started by johnz1 | Post by johnz1
(Sorry to resurrect this thread)
 
Ian, any chance you have an optimal schedule for 16 players?  With somewhere between 12 and 16 games played each.
 
Thanks a lot for your help over the years
Reply Quote Notify of replies  

3  Guestbook / Comments / Round Robin Scheduling
 on: 03/21/17 at 08:08:15 
Started by Guest | Post by Guest
I run a golf league at a private country club.  We are implementing a new division this year using a singles format with a team approach.  Everyone will play with everyone else, against everyone else.  Thank you for providing the scheduling.
Reply Quote Notify of replies  

4  Schedules / Requests / Re: 12 Player Golf League - 9 week schedule
 on: 03/13/17 at 17:54:20 
Started by HGGolf | Post by Ian Wakeling
In the last attachment above you are giving priority to the pairs in a cart, as these are all unique, so I am now confused as to what you want to give priority to.   If you want to have something like your original schedule, then I think the following is better:
 
1  7  2  5  3 11  4 12  6 10  8  9
3  5  4  6  1  9  2 12  7 11  8 10
1  5  2  8  3  9  4 10  6 11  7 12
3  8  4  7  1 12  2 10  5 11  6  9
2  5  3  6  1 10  4 11  7  9  8 12
1  8  3  6  2 12  4 11  5  9  7 10
2  7  4  8  1 11  3  9  5 10  6 12
1  6  4  7  2  9  3 10  5 12  8 11
1  2  3  4  5  6  7  8  9 10 11 12  
 
In the last round both opponents should be played.  However since the pairs (1 2),  (5 6) & ( 9 10) oppose 4 times, you would have to reduce these by one somewhere in the first 8 weeks.
Reply Quote Notify of replies  

5  Schedules / Requests / Re: 12 Player Golf League - 9 week schedule
 on: 03/13/17 at 00:42:43 
Started by HGGolf | Post by HGGolf
^wrong attachment.
Reply Quote Notify of replies  

6  Schedules / Requests / Re: 12 Player Golf League - 9 week schedule
 on: 03/13/17 at 00:39:28 
Started by HGGolf | Post by HGGolf
Thanks for the input. I am restricted to fitting my schedule into 9 weeks, though.
 
I approached the problem by working out Division X (teams A,B,C,D) vs. division Y (E,F,G,H), but keeping the division matchups balanced, sticking with one of each divisional combination.
Over 6 weeks, I used the combinations of AB, AC, AD, BC, BD, and CD vs. EF, EG, EH, FG, FH, GH. This can be set up leaving exactly one unplayed opponent for everyone. (side note: Interestingly, I wasn't able to figure out a combination that allowed for everyone to ride in the cart once with the other division opponent they don't play. At best, I always ended up with one combination that was never in the same foursome).
 
Anyway, after figuring out the Division X vs. Division Y teams for 6 weeks, I figured out X vs. Z and Y vs. Z.
 
So, through 6 weeks, everyone needed to play just one team from each of the other two divisions and their 3 divisional opponents one more time. If I worked it out properly in the first part, fit nicely into the final 3 weeks.
Reply Quote Notify of replies  

7  Schedules / Requests / Re: 12 Player Golf League - 9 week schedule
 on: 03/12/17 at 07:35:53 
Started by HGGolf | Post by Ian Wakeling
I think you may already have a good solution, so I would be interested to know what you have done to get to the schedule in the Excel file.   My insitinct is to try to make 8 weeks where all the foursomes are of the 'Mixed Type' where there are two players from each of two groups, and then have a final round (or two rounds) where the foursomes are of the 'Group Type', with foursomes corresponding to group membership.  I can then think of two strategies for searching for a solution:
 
(1) There are exactly 48 possible pairs of two players where the two players come from different groups.  You could try rearranging these pairs to form an 8 week schedule.  Of course this automatically gives balance for players in a cart together.  I have not tried this option.
 
(2) I noted that there are exactly 1728 possible ways to assign play for a week, where all 3 foursomes are of the Mixed Type.  So I looked for ways of selecting 8 weeks from 1728 to give a schedule.  This was not totally successful, and the method is only finding schedules like the one below, where you would need to add two Group Type rounds, both with 2 matches per player.  This gives 4x replication of the within division matches.
 
The schedule below uses numbers rather than letters, so A=1, B=2, C=3, etc., and it is presented with the same layout as your Excel file, where weeks are rows, and pairs of adjacent columns are carts.

1  8  3  5  2 12  4 10  6 11  7  9
1  7  2  8  3  9  4 11  5 12  6 10
1  5  3  6  2 11  4  9  7 10  8 12
1  6  4  7  2 10  3 11  5  9  8 12
2  7  4  5  1  9  3 10  6 12  8 11
2  7  3  6  1 10  4 12  5 11  8  9
3  8  4  6  1 12  2  9  5 10  7 11
2  5  4  8  1 12  3 11  6  9  7 10
 
1  3  2  4  5  8  6  7  9 11 10 12
1  3  2  4  5  8  6  7  9 11 10 12
Reply Quote Notify of replies  

8  Schedules / Requests / Re: 12 Player Golf League - 9 week schedule
 on: 03/09/17 at 11:25:27 
Started by HGGolf | Post by HGGolf
I think I have a passable schedule. It could probably be optimized a little better to reduce the duplication of players in a cart together and more evenly distribute the number of times non-divisional players are in the same foursome. I will switch up the weeks to distribute match-ups more intuitively, but that doesn't change the format.
 
Any help on optimizing this basic structure would be much appreciated.
Reply Quote Notify of replies  

9  Schedules / Requests / Re: 12 Player Golf League - 9 week schedule
 on: 03/09/17 at 06:38:49 
Started by HGGolf | Post by HGGolf
So, the schedule would end up something like this:
 
Week 1:  
A,E / B,F ; C,I / D,J ; G,K / H,L [ AvsE, AvsB, BvsE, EvsF...]
Week 2:
A,F / C,G ; B,J / D,K ; H,I / E,L
 
...
 
After 8 weeks, A will have played: E/F/G/H/I/J/K/L and B/B/B/C/C/C/D/D, leaving one game vs. D in week 9.
Reply Quote Notify of replies  

10  Schedules / Requests / Re: 12 Player Golf League - 9 week schedule
 on: 03/09/17 at 06:23:21 
Started by HGGolf | Post by HGGolf
Division X: Player A, Player B, Player C, Player D
Division Y: E, F, G, H
Division Z: I, J, K, L
 
Week 1:
Foursome I: A/E/B/F
Carts: A&E / B&F  
A vs. B
A vs. F
B vs. E
E vs. F
Reply Quote Notify of replies