Round Robin Tournament Scheduling

Schedules - You must register to Post and Download => Requests => Topic started by: leeannatk on January 23, 2015, 09:38:24 AM

Title: 8 teams - with 1 double header per week
Post by: leeannatk on January 23, 2015, 09:38:24 AM

I need to get 8 teams scheduled to play 16 games but my field space is limited.
I have 1 field with 5 game slots, 1 day a week for 13 weeks. I believe it have 1 match up play a double header each week that will get me to my number of games but my issue is everytime I try to flesh it out it messes up the round robin because of the way the match ups are. The match ups need to be as even as possible.

I'd so appreciate any help anyone can provide

Title: Re: 8 teams - with 1 double header per week
Post by: Ian Wakeling on January 24, 2015, 04:55:26 AM

Are you sure that you want to play 16 games per team?  I am thinking that 14 games is more natural, as that is a double round robin.

For example you could play:

     S1    S2    S3    S4    S5
 W1 (A F) (C D) (G H) (B E)
 W2 (D A) (E H) (F B) (G C)
 W3 (D F) (G B) (C E) (A H)
 W4 (H B) (G D) (E A) (F C)
 W5 (H C) (B A) (G F) (E D)
 W6 (C B) (F E) (D H) (G A)
 W7 (G E) (A C) (B D) (H F)

 W8 (F D) (E A) (G C) (B H) (C E)
 W9 (E H) (D C) (F A) (G B)
W10 (C B) (F H) (A G) (D E) (H G)
W11 (C A) (B E) (H D) (F G)
W12 (E G) (A H) (D B) (F C) (A D)
W13 (B A) (G D) (F E) (H C) (F B)

and then teams only play once in the late slot (S5).  If you do want 16 games, then you could start with the schedule above add in another 8 games  of your choice in the late slots.

Does that help?

Title: Re: 8 teams - with 1 double header per week
Post by: leeannatk on January 24, 2015, 07:59:23 AM

Ian
Thanks for your response. A couple of things. This is youth baseball, so I need double headers to be back to back. Can't ask a team to play at 10:30 then come back at 5:30.  :)
The reason for 16 games is that we used to play 18 and due to field space have to decrease, I really need to find a way to get them 16 games.
I have 5 slots on 10 Saturday's and 1 weekday slot a week for 8 or 9. I'm realizing I may not get to 16 but need to get as close as possible.
Thanks for your help, this is way above my scheduling ability! And we just added an 8th team in another division that will be in the same boat.

Title: Re: 8 teams - with 1 double header per week
Post by: leeannatk on January 24, 2015, 08:15:05 AM

Oops! I actually have 11 Saturday's!

Title: Re: 8 teams - with 1 double header per week
Post by: wbport on January 24, 2015, 08:39:03 AM

You might want to try rrpair.htm (http://home.comcast.net/~wporter211/realsite/chess_etc/rrpair.htm) and select 8 players and check double round robin.  Designate the team on the left as home or away.  There is a link to create random pairing numbers near the bottom.

Title: Re: 8 teams - with 1 double header per week
Post by: Ian Wakeling on January 25, 2015, 05:30:49 AM

The double headers may mean that there is no solution to this problem.   Consider 7 Saturdays with 5 slots, then the most logical thing to do would be to play W1-W7 above (i.e. a standard round robin for 8 teams) but to make the two teams from S4 play again in S5.  However this schedule can not be completed to 11 weeks since the 21 match ups that remain to be played, in order to complete a double round robin (i.e. all those from W1 to W7 and S1 to S3), are all unique, so it is no longer possible to have a round with a double header.  There may be a way around this, but it would mean allowing weeks where there were two double headers, and consequently two teams with a bye. I am guess that would also be unacceptable.

Title: Re: 8 teams - with 1 double header per week
Post by: leeannatk on January 25, 2015, 08:44:55 AM

Thank you for the responses. This is definitely a challenge. We are actively searching for more field access. If we can get practice fields elsewhere then we can hold up to 3 games a week on weekdays, which would fix my problem completely.
Again thanks for the input!