Double Elimination

Place discussions about upcoming events here in this thread.

Moderators: BeligerAnt, petec, administrator

Remote-Controlled Dave
Posts: 3716
Joined: Sun Apr 03, 2005 5:30 pm
Location: Antrim, Northern Ireland
Contact:

Double Elimination

Post by Remote-Controlled Dave »

Hey all.

As I'm running the next AWS in March I was wondering where we are up to in the progression of the double elimination system. I know Gary has developed one, but my computer won't run it, and I won't have a computer at the AWS. Also, it was noted at the last competition that there were still some bugs in the system eg. lots of repeat fights, some people having to wait for ages before they got to fight at all.

So my questions are, have any of these bugs been addressed? And is there a basic pen-and-paper print out sheet method of doing doulbe elimination charts that I can use on the day, or will someone have a laptop free to run the system that I can use all day?

Thanks in advance.
Die Gracefully Robotics
Winner - AWS 39
Andrew_Hibberd
Posts: 1134
Joined: Tue Jan 20, 2004 12:00 am
Location: London
Contact:

Post by Andrew_Hibberd »

I know pete w had some blank double elim forms, but a quick search turned up nothing. Old ones are on olivers site, and google brings up lots.

The problem with double elimination is the looser side has twice the fights of the winners, which will mean if you are doing well you will have to wait a lot. No real fix for this unfortunately.

My only concern is that the groups should be mixed up a little, so with 4 groups A B C D after round one they should be mixed to A C B D then B C A D etc. As I can't remember which AWS it was but I fought the same robot 3 times with the same robot of mine.
TEAM GEEK!
Remote-Controlled Dave
Posts: 3716
Joined: Sun Apr 03, 2005 5:30 pm
Location: Antrim, Northern Ireland
Contact:

Post by Remote-Controlled Dave »

As I can't remember which AWS it was but I fought the same robot 3 times with the same robot of mine.
Yeah, that was the last event Andy. Though remixing groups after each stage is adding more to do to a day that's already pretty packed. Easier to do on paper than on a computer though I reakon.
Die Gracefully Robotics
Winner - AWS 39
User avatar
joey_picus
Posts: 1137
Joined: Tue Jan 13, 2009 1:51 pm
Location: Lancaster, Lancashire
Contact:

Post by joey_picus »

I seem to remember that was ALBOF/Jigsaw :P Peter usually has some blank sheets from what I remember, it serves fine for the RRC events and for AWSes before Gary and his spreadsheet came along.
Joey McConnell-Farber - Team Picus Telerobotics - http://picus.org.uk/ - @joey_picus
"These dreams go on when I close my eyes...every second of the night, I live another life"
User avatar
peterwaller
Posts: 3213
Joined: Fri Feb 15, 2002 12:00 am
Location: Aylesbury Bucks
Contact:

Post by peterwaller »

I do have the charts available but it is very difficult to draw a chart that mixes up the groups. I don't see how two robots can meet three times unless they qualify as the winner and loser of the group then meet up twice in the final stages which must be very unlikley. I don't see a problem meeting the same robot twice it gives you a chance for revenge especially if the alternative is to be knocked out after one fight.
User avatar
joey_picus
Posts: 1137
Joined: Tue Jan 13, 2009 1:51 pm
Location: Lancaster, Lancashire
Contact:

Post by joey_picus »

The third time was in the non-spinner event in the morning - not a lot that can be done about that really.
Joey McConnell-Farber - Team Picus Telerobotics - http://picus.org.uk/ - @joey_picus
"These dreams go on when I close my eyes...every second of the night, I live another life"
User avatar
BeligerAnt
Posts: 1872
Joined: Wed May 15, 2002 12:00 am
Location: Brighton
Contact:

Post by BeligerAnt »

The spreadsheet is merely an implementation of Peter's charts.
In fact, we always run both in parallel as I don't trust electronics either! :)
The computer only really aids in logging the results and publishing them without the need to transcribe the sheets later.

The problem at the last AWS was that there were so many sheets it was impossible to have everything visible to everyone.

The problem of long waits between fights can possibly be slightly improved by carefully choosing which order the fights are run in, rather than simply running all winners, all losers etc. The spreadsheet can cope with this easily. It may be more difficult for the organisers!

I have looked into the problem of repeating fights and it is very difficult to avoid if we are to allow an arbitrary number of robots in the competition, and more than one robot per team.
To avoid repeating fights you run the risk of meeting your own robot in the losers stream.

If we limit the event to one robot per team and an entry of 8, 16, 32 or 64 robots the draw becomes very simple and we can mix robots around to ensure double elimination with no repeated fights.
I think the downside is much bigger than the upside!

In short, there is no simple solution. If anyone else wants to try to find a solution I for one won't complain!

Edit: @Dave: James and I are happy to help with running the double elimination and we can log it on James's laptop at the same time.
Gary, Team BeligerAnt
Remote-Controlled Dave
Posts: 3716
Joined: Sun Apr 03, 2005 5:30 pm
Location: Antrim, Northern Ireland
Contact:

Post by Remote-Controlled Dave »

Edit: @Dave: James and I are happy to help with running the double elimination and we can log it on James's laptop at the same time.
That would be grand Gary, thank you. This AWS is turning into a group effort, haha.

To avoid repeat fights, can't you just swap one of the competitors over with a random one in another fight, as long as the robot they are swapped with has the same amount of 'lives' left? I know thats complicated, but that's why I thought it might be better to do on paper.
Die Gracefully Robotics
Winner - AWS 39
the16henry16
Posts: 187
Joined: Thu Jan 27, 2011 5:27 pm
Location: aldershot

:P

Post by the16henry16 »

whts a double elimanation
Image
razerdave
Posts: 1562
Joined: Mon Jan 02, 2006 9:40 pm
Location: Carterton, Oxfordshire
Contact:

Post by razerdave »

Double elimination makes sure everyone gets at least 2 fights in a competition before being eliminated. You have to LOSE twice. I have been in a comp where I've gotten to the final and not lost a fight, then lost twice to the other robot in the final
Post Reply