To LUGNET HomepageTo LUGNET News HomepageTo LUGNET Guide Homepage
 Help on Searching
 
Post new message to lugnet.org.ca.rtltorontoOpen lugnet.org.ca.rtltoronto in your NNTP NewsreaderTo LUGNET News Traffic PageSign In (Members)
 Organizations / Canada / rtlToronto / 6673
6672  |  6674
Subject: 
How to Run a Double-Elimination Match
Newsgroups: 
lugnet.org.ca.rtltoronto
Date: 
Tue, 11 Mar 2003 16:48:52 GMT
Viewed: 
502 times
  
Chris, I'm sure software exists, but we need to decide the format before
the software can tell us who plays whom.


Ok, here's how you run single-elimination, for reference:

Let's say you have 8 competitors: A thru H. I'll use the abbreviation
"W1" to mean "winner  of match 1" and "L1" to mean "Loser of Match 1."

Round 1:

Match 1:  A vs B
Match 2:  C vs D
Match 3:  E vs F
Match 4:  G vs H


Round 2:   L1 thru L4: Go cry in their beer / iced tea.

Match 5: W1 vs W2
Match 6: W3 vs W4


Round 3:

Match 7: W5 vs W6  (winner is 1st place; loser 2nd place)
Consolation: L5 vs L6 (winner is 3rd place)

In general, since you eliminate someone each match, if you start with N
people, you play N-1 matches plus a consolation match.

If the number of competitors is not a power of 2 (1, 2, 4, 8, 16, 32),
then you make up a number of "Bye" competitors to fill out the ranks,
and a bunch of people get a "Bye", or a free ticket to the next round,
because they automatically beat their fake opponent.  (We may need to
modify this for Chris' bot)


DOUBLE ELIMINATION:

Ok, Single-elimination is kinda cutthroat, because if you do something
like forget to run the right program or something - *poof*, you're
gone.  In double elimination, you have to lose twice to be eliminated.

How this works, then, is it starts out like single elim.  But although
the winners of round 1 move on, the losers move over to the "loser's
side" of the tree and play off against each other.  The idea being that
is you lose while on the loser's side, you're out becasue you've lost
twice.  If you lose on the winner's side, you go over to the loser's
side.

The end of the match is a little different, you do a playoff between the
top dog in the loser's side, and the winner of the winner's side - I'll
explain farther down:

So, let's start with A thru P (16 competitors)

Round 1: Winner's side:

Match 1:  A vs B
Match 2:  C vs D
Match 3:  E vs F
Match 4:  G vs H
Match 5:  I vs J
Match 6:  K vs L
Match 7:  M vs N
Match 8:  O vs P


Round 2: Winner's side:

Match 9:  W1 vs W2
Match 10:  W3 vs W4
Match 11:  W5 vs W6
Match 12:  W7 vs W8

.... and Loser's Side:

Match 13:  L1 vs L2
Match 14:  L3 vs L4
Match 15:  L5 vs L6
Match 16:  L7 vs L8


Round 3:  Winner's Side:

Match 17:  W9 vs W10
Match 18:  W11 vs W12

... and Loser's Side:

Match 19:  L9 vs W16
Match 20:  L10 vs W15
Match 21:  L11 vs W14
Match 22:  L12 vs W13

... and L13, L14, L15, L16 are out because they lost twice.


Round 4:  Loser's Side (only)

Match 23:  W19 vs W20
Match 24:  W21 vs W22

... while L19 thru L22 are dropped.

Round 5:  Winner's Side

Match 25:  W17 vs W18

... and Loser's Side

Match 26:  L17 vs W23
Match 27:  L18 vs W24

Round 6:  Loser's Side (only)

Match 28:  W26 vs W27

Round 7:

Match 29:  W28 vs L25


Now you have two folks left:  W29 (the "winner" of the loser's side) -
who has lost once; and W25 - top dog - who has never lost.

You put them in a "best of three" match, but W25 - the top dog, starts
with a 1-0 advantage since she's never lost.  In other words, the
underdogs has to come back 2-0 in order to win outright.  Then you're
done.

Confused?  I'm not :)

The end result is either 30 or 31 matches.  In general, If you've got N
competitors, it takes 2N or 2N+1 matches to finish, since each person
must lose twice to get knocked out.


ROUND ROBIN:

This is what we normally do: Everyone plays everyone.  This requires (N
x (N-1)) / 2 matches.  So, while it works for small numbers (7
competitors = 21 matches) it doesn't for large numbers (16 competitors =
120 matches)

It's also possible to combine formats. Ie:  round-robin in small groups,
and the winner go on to a double or single-elim tourney.



I'll volunteer to be there to help run the matches :)

Jeff E



Message has 3 Replies:
  Re: How to Run a Double-Elimination Match
 
I'M BACK! I was just telling Chris about some software I wrote to score our SUMO matches for the Lafayette club. It sort of combines the elimination with a round robin. It's hard to explain in 25 words or less, but it's been used several times with (...) (22 years ago, 11-Mar-03, to lugnet.org.ca.rtltoronto)
  Re: How to Run a Double-Elimination Match
 
(...) Okay. We usually have anywhere from 8-12 entries, so that's not a bad guess at all. (...) That fits okay, because 7x3minutes is only 21 minutes and we have a total of an hour to officially entertain, according to the schedule. (...) :) (...) (...) (22 years ago, 11-Mar-03, to lugnet.org.ca.rtltoronto)
  Re: How to Run a Double-Elimination Match
 
In lugnet.org.ca.rtltoronto, Jeff Elliott writes: a great explanation of single and especially double elimination which I snipped but which I have to try to remember since I'll be running something at GenCon Indy ... (...) This is often used for (...) (22 years ago, 11-Mar-03, to lugnet.org.ca.rtltoronto)

7 Messages in This Thread:




Entire Thread on One Page:
Nested:  All | Brief | Compact | Dots
Linear:  All | Brief | Compact
    

Custom Search

©2005 LUGNET. All rights reserved. - hosted by steinbruch.info GbR