Strange initial pairing in tournaments

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1

This is not the first time people are confused by the pairing methods for tournaments. A document that actually describes what they do would be nice…

Nevertheless I think that this behavior of the “slaughter” pairing is a bug. According to senseis ( Group Pairing at Sensei's Library ) the strongest player should play against the weakest, second strongest against second weakest etc. So in our tournament 1st 2021 OGS Yeonwoo's Cup I would have expected the following matchup:

1kyu player auto advances
1k vs 19k
1k - 17k
1 - 15
2 - 13
4 - 12
4 - 10
4 - 10
4 - 10
5 - 9
6 - 9
7 - 9
8 - 9

Instead we got

1 - 2
1 - 19
1 - 17
1 - 13
4 - 12
4 - 10
4 - 10
4 - 10
5 - 8
6 - 9
7 - 9
9 - 9
15 auto advance

I can understand why you might choose a random player to be left out, but why am I in a 1kyu vs 2kyu game in this tournament? oO

3 Likes
2

I wonder if there might be a link with a possible misinterpretation of ranks in allocating handicaps?

1 Like
3

according to the way it is described on senseis, all 1kyu and 2kyu players should play against 13 kyu or weaker players (in this case). around the median (8kyu to 9kyu) a match of about equally strong players should happen - but definitely not at either end

EDIT: The confusion you mentioned is about fraktional ranks (0.5kyu vs. 1.5kyu etc.) if I understood it correctly. That effect is much too small to explain this.

4

Yes, I was just coming to that realisation myself. Sorry.