Recent Posts

1

Requests / Re: Olympics Scheduling - 12 teams - 8 events

« Last post by Ian Wakeling on July 10, 2025, 03:28:46 AM »

What you are asking is impossible. The "each other at least once" criterion requires a team to play at least 11 games, the "not play the same game more than once" criterion requires each team to play no more than 8 games. The schedule here is about the best you can do.

2

Comments and Thanks / Re: canasta tournament

« Last post by Ian Wakeling on July 10, 2025, 03:23:31 AM »

Hi, look here for the whist tables.

3

Requests / Olympics Scheduling - 12 teams - 8 events

« Last post by samijo512 on July 09, 2025, 01:19:39 PM »

Hello! Maybe I am losing my mind but I am trying to figure out how to schedule a backyard Beer Olympics bracket.

We have 12 teams of 2 wanting to compete in 8 different events. I would like each team to play each other at least once but not play the same game more than once. Any way you can help me figure out how to make this bracket schedule?

4

Comments and Thanks / canasta tournament

« Last post by bks2550 on July 09, 2025, 11:09:40 AM »

Hi,

I am hosting a canasta tournament for (8 people,12 people, 16 people, or 20 people) in a couple of weeks. It varies according to the number of ladies who respond.

We would like everyone to partner with each player 1 time in the tournament. There will be 4 ladies at each table.

We play 6 games 

Are you able to draw up a schedule for us?


Thank you,

5

Requests / Re: Bjerring tournament templates

« Last post by cvvcdad on July 06, 2025, 07:50:14 PM »

Thanks so much Ian!

11 rounds is fine, and better timewise than 13 rounds, so this is perfect for what I need to do on the court.

If you come up with anything else I'd welcome that too, of course. I have a lot of 3v3 and 4v4 solutions that I worked out rather inelegantly, but I lack 5v5 schedules. If/when you have some time (no hurry) I'd love to have 5v5 for 10 and 11 players. If it makes it simpler, the position ("P1" etc.) is irrelevant for what I use this for.

Again, thank you...it's much appreciated!

6

Requests / Re: Bjerring tournament templates

« Last post by Ian Wakeling on July 06, 2025, 09:43:16 AM »

Hi, I think if you have exactly the right number of players and number of rounds, then there may be a perfect tournament, but most of the time, with other numbers of players and rounds the only thing possible will be a long way from perfect.  How far away from perfect probably depends on the search algorithm used, and this makes it difficult to know if you you have found an optimal solution.  I don't currently have an software that might help here, but I will think about some options.

Here is one perfect solution for 12 players in 11 rounds - where each player partners with each other player 5 times and opposes each other player 6 times.

 P1 P2 P3 P4 P5 P6    P1 P2 P3 P4 P5 P6
( 3 12  9 11  5  1) v ( 4  6 10  7  8  2)
(12 10  3  9  7  4) v ( 1 11  5  8  2  6)
( 8  7 12  6  3  5) v (11  2  4  9 10  1)
( 3 11  8  2  4 12) v (10  5  1  7  6  9)
(11 10  7  5 12  2) v ( 8  1  9  6  4  3)
( 7  6  4  1 11 12) v ( 2  9  5  8  3 10)
(10  9  6 12 11  8) v ( 1  2  3  4  5  7)
( 6  1 12  3  2 10) v ( 5  4  7 11  9  8)
( 9  8  2 12  1  7) v ( 4  3 11  5 10  6)
( 5 12  1 10  8  4) v ( 2  7  6  3  9 11)
(12  5  2  4  6  9) v ( 7  3  8 10  1 11)

If P1 to P6 are 6 positions, then each player appears twice in 5 positions, and once in the other  position.

Is 11 rounds something that is practical?  I guess another perfect schedule might be possible for 13 players and 13 rounds, with each player having one bye.

7

Requests / Bjerring tournament templates

« Last post by cvvcdad on July 05, 2025, 08:30:19 PM »

Hi! The help given here is amazingly valuable! If you can help with this, it will be greatly appreciated by many, many volleyball coaches.

I often run Bjerring tournaments during practice, and also for school vb tryouts. It's not really a problem to define Bjerring tournaments for the number of players at practices. But tryouts are a completely different animal.

In general, what I need is the teams for each round of a 6v6 Bjerring tournament for n players. A Bjerring tournament is player-defined instead of team-defined, so the mixing from round to round is in terms of which players are playing together and which players are they playing against, and NOT which teams are playing each other in a particular round. There are no defined teams, just two sets of 6 players each game.

An ideal Bjerring tournament has any given player playing with every other player the same number of games and playing against every other player the same number of games. I assume that isn't possible for every value of n; if not a variance of 1 from player to player would be fine.

A quick example: the first game of a Bjerring tournament has players 1/2/3/4/5/6 vs players 7/8/9/10/11/12; the second game is players 1/3/5/7/9/11 vs players 2/4/6/8/10/12; etc. When the tournament is over, player 1 will have played x times with every other player, and z times against every other player. Again, this is the PERFECT Bjerring tournament, but a slightly-less-than-perfect format would work too.

What would be amazingly valuable is a tool that allows a coach to input the number of players, with the output being the player assignments for each game of 6v6 for the number of rounds needed. What would be even more valuable would be a tool that does this while allowing for various-sized games -- e.g., a tournament of all 6v6 games, a tournament of all 5v5 games, etc.

I know that's a LOT to ask; alternatively (and this might be a lot to ask too), tables defining 6v6 games for Bjerring tournaments for 12 players, 13 players, etc. up to 24 players would be great! I would likely never bother you again!

Thanks so much in advance for any help you can give to all of us vb coaches out here!

8

Requests / Re: Am I asking for the impossible?

« Last post by Mike Von on June 24, 2025, 09:50:56 AM »

Ian,

You are amazing!



Thank you very much, our little tournament will run smoothly now.

Mike

9

Requests / Re: Am I asking for the impossible?

« Last post by Ian Wakeling on June 24, 2025, 03:38:46 AM »

Here are some possibilities for your 8 round schedule - the 16 player one is best since everyone has the same number of games.


13 players (players 1 to 5 play in every round, the others each have one bye)

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

14 players (players 13 & 14 have 6 games, the others have 7 games)

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

15 players (players 1-9 have 6 games, players 10-15 have 7 games)

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

16 players (all players have 6 games)

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


Hope that helps,

Ian

10

Requests / Re: Am I asking for the impossible?

« Last post by Mike Von on June 20, 2025, 03:32:07 PM »

Ian,

I searched the site but couldn't find:

doubles tennis, changing partners and opponents every round
3 courts
8 rounds
player numbers can be 13, 14, 15, 16
play with a player a maximum of one time
minimize the number of times you play against any player

Are there any solutions that meets these requirements?

Any help is much appreciated.