Life In 19x19

It may not appeal to everyone's sensibilities, but the Ing Masters tournament has an unusual way of pairing players this year (see: http://usgo.org/tournaments/crosstab/band-matrix/92).

The tournament has thirty two players and five rounds. It is a bit like a single elimination tournament with an ongoing losers tournament to determine 3rd-32nd place. Players are seeded by strength. With normal pairings, seed #1 would play seeds #32, 16, 8, 4 and 2 if all higher seeds won their games.

This year, the pairings do not work as usual. In round one, the pairings were as follows:

Round 1
1 plays 17
2-18
...
16-32

and in round two:

1 plays 9
2-10
...
8-16
17-25
18-26
...
24-32

(the higher seed won every game in round 1).

Undoubtedly, the reason for this was the wider than usual spread of strengths. The 1 seed is Mingjiu Jiang, while some players at the lower end are AGA 3d. The new system gives slightly more interesting games in the first round.

It would be a nice question exactly which players have an easier or harder draw than in a standard tournament of this form.

So instead of a slaughter pairing an fold pairing

See [sl=GroupPairing]Group Pairing[/sl]

If the start ranking is the same as the end ranking, then a foldpairing is harder on the higher ranked players (on average they play against players who end with more wins)

in most tournaments fold pairiung is used because it also gives higher [sl=SOS]SOS[/sl] scores

I think it is the right choice

The player numbers posted in the tournament tournament grid at http://usgo.org/tournaments/crosstab/band-matrix/92 don't correspond to the player seedings. You can't use them to figure out what kind of pairing is in effect.

Why are 3d players involved. Surely there must be 32 player 5d and above you are interested. It not I see that as a sad state of affairs.

DrStraw wrote:Why are 3d players involved. Surely there must be 32 player 5d and above you are interested. It not I see that as a sad state of affairs.

That's pretty much the way it is. It's a very small field this year in Colorado.

Also, the requirements are no lapse of AGA membership in last 12 months and 10 rated games.

pwaldron wrote:The player numbers posted in the tournament tournament grid at http://usgo.org/tournaments/crosstab/band-matrix/92 don't correspond to the player seedings. You can't use them to figure out what kind of pairing is in effect.

Are you sure? It seems like a strange coincidence that it should be paired so exactly for the first two rounds if those numbers are meaningless. Is there some other reason it should work like that? (Also, even if not exact, it's clearly the stronger players at the top of the list).