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RaiZenGar
09-27-2014, 11:43 PM
Your Display Name: RaiZenGar

Bug Description:
In Swiss 8-player, Bye does not always go to a person with the lowest record. In the recent tournament E8A6208C1E640 my first round opponent got two Byes in a row after losing to me leaving me to fight the 0-2 in the last round as a 1-1. My last round opponent should have gotten the bye and I should have fought one of the other 1-1's. All other possible 1-1 pairings should have been valid since my first round opponent had only played me.

In swiss, players of like record should be _randomly_ paired together against someone that they haven't played yet starting with the best records and pairing down one level (no more than two people in a given level should be playing outside of it: one up, one down) if there's an uneven number of players remaining with that record. A Bye should never go to someone who is not 0-X unless there are literally no 0-X's and then it should go to someone who has the lowest record. Rather than randomly pairing, it seems to have some weird bracket in mind and Bye's seem to screw it up sometimes.

I've also noticed that 1st round swiss pairings do not seem to be random. They seem to be based on join order which is highly exploitable.

Steps to Reproduce:
Have someone drop from the tournament so that a bye is introduced

Frequency:
Occasional

Additional Information:

ossuary
09-28-2014, 07:09 AM
It is not broken. There are more factors in play than you are taking into account.

Please go to this article, and scroll down to the section titled "Swiss Pairings" for an explanation of how their system is built:
https://hextcg.com/scheduled-tournaments-and-swiss-pairings/

Edit: I have noticed that join order will sometimes be the same as first round pairings, but haven't been in enough tournaments to accurately calculate probability. It would be nice if someone would look at that piece of it, though, because I agree if it just pairs you in order for the first round, that's bad.

mach
09-28-2014, 09:20 AM
It is not broken. There are more factors in play than you are taking into account.

Please go to this article, and scroll down to the section titled "Swiss Pairings" for an explanation of how their system is built:
https://hextcg.com/scheduled-tournaments-and-swiss-pairings/


It's impossible to tell without seeing the complete details, but from what the OP said it doesn't seem like what happened is following what that article said should happen.

RaiZenGar
09-28-2014, 10:19 AM
It is not broken. There are more factors in play than you are taking into account.

Please go to this article, and scroll down to the section titled "Swiss Pairings" for an explanation of how their system is built:
https://hextcg.com/scheduled-tournaments-and-swiss-pairings/



I've read that article before, and what I'm describing does not follow the guidelines at all. The 0-2 in the last round hadn't had a Bye (obviously), so there was no reason to give it to the 1-1 that already had a Bye, much less ANY 1-1. There's no circumstance in an 8 player tournament where only 1 person has dropped where you give the Bye to anyone other than a 0-X. I hadn't played any of the other 1-1's and the guy who got the Bye certainly didn't play anyone other than me, so there were plenty of valid 1-1 to 1-1 pairings.

ossuary
09-28-2014, 11:53 AM
Then I guess we'll have to hope Chark sees this and comments, as he did say at the time that he would monitor any feedback from players relating to the tournament pairings not working as expected.

jonsnow2000
09-29-2014, 06:50 AM
I have seen this sort of situation before in my draft tourneys. Sometimes I even made a posting here describing what happened, but there was never any official reaction to it.