What is tiebreaker in tournaments?

[Vanatox]

Here, on 4th, 5th and 6th places are players with the same amount of points. In past tournaments i have noticed that tie-breaker is sum of opponents elo, but here is not the case, because player on 4th place has the highest elo among the tied ones.

https://boardgamearena.com/tournament?id=172823

[Mathew5000]

The tournament you linked to is a round robin. See the following thread: viewtopic.php?t=25178

A poster there says that in round-robin tournaments, tied players are ranked based on seniority of their BGA accounts.

You can also look at the following threads:
viewtopic.php?t=11553
viewtopic.php?t=22929
viewtopic.php?t=23562

[Meeplelowda]

A poster there says that in round-robin tournaments, tied players are ranked based on seniority of their BGA accounts.

So I don't know how ties in round robins are handled in the real world, but age of account seems like an arbitrary way to do it. I guess you can't use a "strength of schedule"-style tie breaker because everyone plays everyone so it will be equal.

[Mathew5000]

In a round-robin, if there are two tied players they have necessarily played each other once, so the tiebreaker could be the result of that head-to-head game. But that doesn't work when there are three or more tied players.

In my view "age of account" should never be used as a tiebreaker. It would be much better to just call it a tie! If three players have exactly the same performance within the tournament, then just say it's a three-way tie for 7th place (or 1st place, or whatever).

Some relevant reports you may wish to vote for:

#31816: "Non elimination tournaments results:tiebreaks should be based on head-to-head results where possible"

#33067: "Round-robin tournament : perfect tie was broken for no apparent reason"

#54909: "Configurable Tie Breaker for Swiss and Round Robin Tournament"

#63019: "Tie bracker in round robin"

[T72on1]

I think the tournament creator can choose what has to be used as tiebreaker.

I agree that seniority here on the site seems like a very arbitrary tiebreaker. Having said that, sometimes it's not an option to just have a tie. For example in tournaments with a knock-out stage. So I guess something has to be used as a tiebreaker at that point.

[Mathew5000]

I think the tournament creator can choose what has to be used as tiebreaker.

No. When creating a round-robin tournament, there is no option to set a tiebreaker criterion.

I agree that seniority here on the site seems like a very arbitrary tiebreaker. Having said that, sometimes it's not an option to just have a tie. For example in tournaments with a knock-out stage. So I guess something has to be used as a tiebreaker at that point.

Yes, good point. This would apply in a "Group Stage" tournament.