Round Robin Tournament Scheduling

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21
Requests / Re: Please help!
« Last post by kjgrossman on June 27, 2022, 02:29:57 PM »
Okay, for my group of 64 I am just going to play 3's and I got that figured out.  So, what I need is a Beijing's doubles schedule for 31 players on 6 courts for 30 rounds and 
33  players Beijings doubles  on 6 courts for 30 rounds.  Is that do able?  THANK YOU SO MUCH!!
22
Requests / Re: Please help!
« Last post by Ian Wakeling on June 27, 2022, 09:54:59 AM »
Approximately how many rounds do you think you can play?  I need to have some idea.

Is the size of 64 player group absolutely fixed?  I ask as if you have 10 courts with 6 players per court, then a schedule for 60 players is obviously best.
23
Requests / Re: Please help!
« Last post by kjgrossman on June 27, 2022, 09:20:42 AM »
Ahhh...yes I did not do a very good job thinking this through in my description. 

I have 5 nets but because they are playing only on half the court I actually have 10 courts available for the group of 64 and 6 courts available for the group of 31 and 32.  After reading your reply you are probably correct and to prevent too many kids from sitting out in the group of 64 lets change that to groups of 3's playing on 10 courts.  Does that sound like a better idea?  

Thank you so much for your help!!
24
Requests / Re: Please help!
« Last post by Ian Wakeling on June 27, 2022, 04:01:22 AM »
To me it seems that you will have way too many players sitting around doing nothing.  Taking 32 players and 3 courts of doubles as an example, you could play 8 rounds as follows:

    Court 1      Court 2      Court 3
  (32 16 11 26) (30  6 23 22) (15  1 19  7)
  (25  9 12 27) (31  7 24 23) (16  2 20  8)
  (26 10 13 28) (32  8 17 24) ( 9  3 21  1)
  (27 11 14 29) (25  1 18 17) (10  4 22  2)
  (28 12 15 30) (26  2 19 18) (11  5 23  3)
  (29 13 16 31) (27  3 20 19) (12  6 24  4)
  (30 14  9 32) (28  4 21 20) (13  7 17  5)
  (31 15 10 25) (29  5 22 21) (14  8 18  6)

Here no two players appear on court together twice, so they are free to split into two-vs-two any way you like. There will be 20 players with a bye in each round, and any one player has 3 games and 5 byes.

Can you state how many rounds you will be able to play?  Are there more than 5 courts available?
25
Requests / Please help!
« Last post by kjgrossman on June 27, 2022, 12:43:30 AM »
Hi,
I am a new HS volleyball coach and I am running my first VB camp.  I want to have the girls playing lots of matches with various team sizes.  I was hoping you could help me with the various match ups.

64 players on 5 courts playing doubles


32 players on 3 courts playing doubles
32 players on 3 courts playing triples

31 players on 3 courts playing doubles
31 players on 3 courts playing triples


Any help you can give would be sooooo great!!  I had a website I used a few years ago and it is no longer online and I waited till the last minute thinking I had a resource.  My camp starts Tues. 6/28. Is there anyway you could help me by then? Thank you for your time!
26
Requests / Re: Whist style round robin - 25 players, 6 courts, 11 rounds
« Last post by Cindi on June 25, 2022, 12:12:57 PM »
Thank you, Ian. This is amazing as always! :)
27
Requests / Re: Whist style round robin - 25 players, 6 courts, 11 rounds
« Last post by Ian Wakeling on June 22, 2022, 03:43:31 AM »
Hi Cindi,

I don't have a way of making a good 11 round schedule, but I can make a 10 round one.  The schedule below has the properties you want, all partners different and all opponents different, players on court with all others at least once and at most twice.  Of course the 10 players in the last column who have the bye will have one less game than the rest. Hope that helps.

Ian


  ( 1 20 v 19 23) (12 14 v 24 15) (21 16 v  2 13) (11 10 v 17  9) (18  8 v 22  3) ( 7  5 v  4 25) ( 6)
  ( 2 16 v 20 24) (13 15 v 25 11) (22 17 v  3 14) (12  6 v 18 10) (19  9 v 23  4) ( 8  1 v  5 21) ( 7)
  ( 3 17 v 16 25) (14 11 v 21 12) (23 18 v  4 15) (13  7 v 19  6) (20 10 v 24  5) ( 9  2 v  1 22) ( 8)
  ( 4 18 v 17 21) (15 12 v 22 13) (24 19 v  5 11) (14  8 v 20  7) (16  6 v 25  1) (10  3 v  2 23) ( 9)
  ( 5 19 v 18 22) (11 13 v 23 14) (25 20 v  1 12) (15  9 v 16  8) (17  7 v 21  2) ( 6  4 v  3 24) (10)
  (15  3 v 20 21) (24 23 v  7 22) (18 11 v 25  2) ( 6  5 v  9 12) ( 8 17 v 13 19) (14  4 v 10  1) (16)
  (11  4 v 16 22) (25 24 v  8 23) (19 12 v 21  3) ( 7  1 v 10 13) ( 9 18 v 14 20) (15  5 v  6  2) (17)
  (12  5 v 17 23) (21 25 v  9 24) (20 13 v 22  4) ( 8  2 v  6 14) (10 19 v 15 16) (11  1 v  7  3) (18)
  (13  1 v 18 24) (22 21 v 10 25) (16 14 v 23  5) ( 9  3 v  7 15) ( 6 20 v 11 17) (12  2 v  8  4) (19)
  (14  2 v 19 25) (23 22 v  6 21) (17 15 v 24  1) (10  4 v  8 11) ( 7 16 v 12 18) (13  3 v  9  5) (20)
28
Requests / Whist style round robin - 25 players, 6 courts, 11 rounds
« Last post by Cindi on June 21, 2022, 12:32:27 AM »
Hi Ian,

I'm looking for a schedule for a whist style round robin, 11 rounds total with 25 players and 6 courts, with 1 player having a bye each round. So each player will have a unique partner each round and will oppose 22 unique players, favoring mixing up players from round to round. Not sure if a perfect schedule is possible, but trying to get as close as possible to each person playing with all 24 players either as a partner or opponent, not opposing the same player twice and each player not sitting out more than once. Thank you so much!

Cindi
29
Requests / Re: Am I asking for the impossible?
« Last post by Ian Wakeling on June 16, 2022, 03:55:53 AM »
I have been picking off the easy ones above, as they are accessible to a cyclic solution where a small number of base rounds need to be found.  For example the 16 player schedule above is defined by rounds 1 and 4 only, the other rounds are derived by simple permutations.  This does not work all the time, specially for the less symmetric schedules with empty courts.

I have outlined some of the features of a general solution above, it would need to count the frequency of the three types of player pairs, and the frequency of the byes.  Then look for a small change to the schedule that makes the sum of the squares of the frequencies smaller.  You could program this from scratch, or you might be able to set this up in a constraint programming package.
30
Requests / Re: Am I asking for the impossible?
« Last post by canadave on June 15, 2022, 08:59:21 PM »
Thanks very much for these improvements :) Very much appreciated. Is there any programmatic way to try to improve the other sheets?