Round Robin Tournament Scheduling

Schedules - You must register to Post and Download => Requests => Topic started by: Jono on December 30, 2013, 02:46:37 PM

Title: Longer seasons
Post by: Jono on December 30, 2013, 02:46:37 PM

Is there a general strategy for longer seasons?

I have 8 teams, and will play a 21 game schedule, so each team places each other team 3 times. We want to distribute the, for example, three times team A plays team B across the season, so I think I can just use the standard algorithm 3 times and permute the team order each time. (e.g., Fred's team is team A during the first 7 games, then team C, then team F, during the next 7 and last 7 games).

I think the only constant this will not solve for is I want to make sure of the three times A plays B, A and B are each the home team at least once.

The other slight wrinkle we have is that even rounds are played during the week and odd rounds are played on Saturdays. So, in addition to wanting to make sure team each team plays court 1 an equal number of times, I actually want to make sure it's played an even time in even rounds and an even time in odd rounds - as much as possible - because the weekday venue is different than the weekend venue.

--jono

Title: Re: Longer seasons
Post by: Ian Wakeling on January 01, 2014, 07:21:54 AM

Hi Jono,

If I understand correctly you are asking for both court balance and home-away balance.  This is possible,  but it is beyond what you will get from the Excel generator, as essentially this does one or the other.

Below is a 14 round example where I have rearranged rounds 1 to 7 slightly, to form rounds 8 to 14.  If a game is (A B), then I intend that team A is the home team and B is the away team. I have simply reversed all the games (A B) in rounds 1 to 7 to become (B A) in rounds 8 to 14 and have rotated the courts/columns along one.   The result is that if the first game between any 2 teams is played in round 1, 3, 5 or 7, then the rematch between the same 2 teams will be played in either rounds 8, 10, 12 or 14, so balancing home/away and week-day/Saturday.   If you want 21 rounds, then I think you could just take rounds 1 to 7 and rotate the columns twice.

Hope that helps,

Ian.

      C1    C2    C3    C4
 r1  (3 2) (6 7) (8 1) (5 4)
 r2  (2 5) (1 3) (4 6) (7 8)
 r3  (4 7) (5 3) (8 2) (6 1)
 r4  (3 8) (1 4) (7 5) (2 6)
 r5  (7 1) (5 8) (6 3) (4 2)
 r6  (8 6) (2 7) (3 4) (1 5)
 r7  (6 5) (4 8) (2 1) (7 3)
 r8  (4 5) (2 3) (7 6) (1 8)
 r9  (8 7) (5 2) (3 1) (6 4)
r10  (1 6) (7 4) (3 5) (2 8)
r11  (6 2) (8 3) (4 1) (5 7)
r12  (2 4) (1 7) (8 5) (3 6)
r13  (5 1) (6 8) (7 2) (4 3)
r14  (3 7) (5 6) (8 4) (1 2)

Title: Re: Longer seasons
Post by: Jono on January 09, 2014, 05:32:59 PM

Excellent - that sounds like a good strategy.

Do you know of any strategies for producing a bye-less schedule for odd teams. My thought is to instead of giving each team a bye in each round, one team will play twice in each round. I'd rotate who plays in the "bye" slot, I should be able to avoid breaking balance.

Last year I tried to do this by scheduling the last round of the tournament this way. Each round I'd take the team with a bye and put in their game from the last round. I wasn't able to fully automate it, but it seems like a reasonable course of action.

--jono