Round Robin Tournament Scheduling

Recent Posts

1
Requests / Re: 18 person euchre tourny
« Last post by Markie on March 20, 2023, 07:14:23 AM »
Hi Ian, ... this works perfectly !!

Is there also a schedule for 7 players on 1 court ? ... 4 players & 3 bye's.
2
Requests / Re: Whisp schedule for pickleball
« Last post by Ian Wakeling on March 12, 2023, 10:09:42 AM »
I looked at just one of the irregular scenarios, that for 15 players on 3 courts, and I have shown below the smallest possible schedule where all pairs of players partner at least once.

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

Note that players 1,2,3,13,14 & 15 have 15 games while the other players have 14 games.
3
Requests / Re: Whisp schedule for pickleball
« Last post by Ian Wakeling on March 12, 2023, 04:49:04 AM »
I think it is important to at least try to balance the opponents.  If the number of players corresponds to a whist schedule (4n or 4n+1), then the possibility exists of trying to rearrange things to reduce the number of courts.  So for example if you follow the link near the top of page "visit the pages that inspired the forum" and then find the whist table for 16 items - then that schedule can be rearranged by turning table 2 into 5 new rounds as follows:


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

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

The order of the rounds should then be randomized so that player 16 does not have all their byes at the end.  I am sorry that I don't have off-the-shelf solutions for many of your requests, but I will try to add more schedules if time permits.
4
Requests / Re: Whisp schedule for pickleball
« Last post by Jschramm on March 11, 2023, 11:23:48 AM »
Ian
the opponents do not have to be equal for each player, the only requirement is that each person plays with every other player. It is timed games at 7 minutes each and it takes roughly 4 hours to do the entire thing. 
5
Requests / Re: Whisp schedule for pickleball
« Last post by Ian Wakeling on March 11, 2023, 11:06:50 AM »
With the exception of 20 players on 5 courts, no balanced whist schedule is possible.  Really you need to consider what your objectives are?  How many rounds are you looking to play - is there a maximum because of time constraints?  Do you want all (or most) pairs of players to partner each other once?  Do you want all (or most) pairs of players to play each other (either as partners or opponents) at least once.  Is it important that all players have exactly the same number of games?

There is an 18 player schedule here that might help.  Does that look useful, or is it too long perhaps?
6
Requests / Whisp schedule for pickleball
« Last post by Jschramm on March 08, 2023, 06:41:57 PM »
I am in need of help for a whisp schedule for these multiples on 5 courts (some players would have a bye each round) for a long pickleball round robin
24, 23, 22, 20 (5 courts)
21, 20, 19, 18, (4 courts)
17, 16, 15, 14 (3 courts)

7
Requests / Re: Need help putting together 7 league schedule
« Last post by Ian Wakeling on March 07, 2023, 02:14:38 AM »
It is best to start by looking for a 21 week schedule, as this can be fully balanced, and then throw away the last week.  With 21 weeks there are 84 games in total which can be arranged so that all teams:
  • play each other exactly 4 times
  • play on each field exactly 12 times
  • play 12 games at the earlier start time
  • play 12 times at the later start time
  • play exactly 3 double headers
For example the following schedule has all these properties - the dashed line separate the 21 weeks.

 F1    F2
(1 7) (4 6)
(1 2) (3 5)
------------
(1 4) (5 7)
(3 6) (2 4)
------------
(3 7) (2 6)
(4 7) (1 5)
------------
(2 5) (3 4)
(1 6) (2 7)
------------
(2 3) (4 5)
(1 3) (6 7)
------------
(3 7) (5 6)
(2 4) (1 5)
------------
(1 6) (3 4)
(5 7) (2 6)
------------
(5 6) (1 3)
(4 7) (1 2)
------------
(2 5) (1 7)
(3 6) (4 5)
------------
(1 4) (6 7)
(3 5) (2 7)
------------
(4 6) (2 3)
(1 4) (5 7)
------------
(2 7) (1 3)
(2 4) (5 6)
------------
(2 5) (1 6)
(3 6) (4 7)
------------
(3 6) (4 5)
(1 7) (2 3)
------------
(1 5) (2 6)
(4 6) (3 7)
------------
(3 5) (1 2)
(6 7) (3 4)
------------
(4 7) (2 5)
(3 5) (1 6)
------------
(1 2) (3 7)
(5 6) (2 4)
------------
(1 4) (6 7)
(2 3) (1 5)
------------
(5 7) (3 4)
(2 6) (1 7)
------------
(2 7) (4 6)
(4 5) (1 3)

Note that the team with the double header in the week that you throw away will end up with one less game than the other 6 teams, so removing the last week above will mean that team 4 has 22 games, while the others all have 23 games.
8
Requests / Need help putting together 7 league schedule
« Last post by jorgie97 on March 05, 2023, 02:28:00 PM »
I am going crazying trying to put together a seven team league baseball schedule. Essentially, we have two fields with two games being able to played on each field. We have 7 teams and do not want any byes. We want each team to have an equal number of double headers and play each other as close to as the same times as possible as we are looking to play for 20 weeks. Would any of you guys be able to help put together. Thanks!
9
Requests / Re: 12 and 16 player tennis round robins with 7 rounds
« Last post by Crusty on March 03, 2023, 06:05:49 PM »
Thanks so much for these schedules, Ian!  We will use them at our tournament this weekend. The advice you provide on this forum is much appreciated!
10
Requests / Re: Volleyball Schedule - 12 teams, 2 Courts (A VS B, C VS D), 11 weeks
« Last post by CLD on March 02, 2023, 03:54:15 PM »
ok - thank you :)