Pairing for round of 16,
Choi Kihoon vs Won Seongjin
Lee Sedol vs Shi Yue
Na Hyun vs Jiang Weijie
Lee Younggu vs Xiao Zhenghao
Park Junghwan vs Lian Xiao
Choi Cheolhan vs Gu Li
Kang Dongyoon vs Peng Liyao
Lee Changho vs Li Kang


More pictures,

http://www.cyberoro.com/news/news_view.oro?num=516706

http://www.cyberoro.com/news/news_view.oro?num=516707

Looking at them by nationality, the pairings look like this:

K v K
K v C
K v C
K v T
K v C
K v C
K v C
K v C

I infer that there is a pairing rule that two people of the same country are not paired against each other unless absolutely necessary. Does anyone know the pairing algorithm?

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Btw, the Korean Baduk Association site has some nice photos at http://www.baduk.or.kr/info/report_view ... =&keyword= . With everyone together in one big hall, it might seem to get a little noisy during byo-yomi. But they do get a long main time (3 1/2 hours?), and I suppose everyone is concentrating on his own game, anyway.

If you are a beginning Hangul reader like me, you might find the training quiz at http://www.aeriagloris.com/LearnKorean/ useful (I'm starting to be able to read the names of the pairings, for example).

Joaz, the pairings are random; from the photos, we see that the players all pick a fan at the start with 2 fans of the same number from 1 to 16, and that determines the pairings. It seems a bit strange that there is no seeding, but of course the top 32 in the world are all gods anyway.

i don't know, do they repeat the random pairing in subsequent rounds? i was under impression that it is done only once at the beginning.

but if the pairings are not based on the drawn numbers (and i don't see a connection between numbers and round #2 pairing), it is unclear why to draw them for only one round

furthermore, not having a fixed bracket takes away an important advantage of the knock-out for me - you can't predict who will meet whom in the following rounds. though i perfectly understand how would it suck to go all the way to Korea and play players from my home country.

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I might be wrong, but probably not.

Hikaru no Go 8 is about the insei elimination tournament, in which inseis, as well as outsiders who qualify, battle to get a place in the pro tournament. Everyone draws a folded paper from a box and the matched numbers play. In the tournament, you have to get 3 wins out of 5 games to qualify, so after 3 games there is a re-drawing without those who win 3 or lose 3. In the story, the last drawing on the 5th day has an odd number of people, and Hikaru draws a blank paper, a bye, so qualifies. (I've been rereading Hikaru lately to practice my Japanese.)

My understanding is that the initial pairing determines your spot in games 1 through 16, and so determines the entire draw. For example, you get the tournament table in http://igokisen.web.fc2.com/wr/lg.html . But yes, I agree that it does seem a bit strange. Fair, though!

I don't know whether pairing selection for this round is just random or not. Some tournament try to avoid players from same country playing each other and others don't.

I can remember seeing a first-round pairing in an international tournament that I think was Lee Sedol vs. Gu Li, and just going "What!?". I suppose the pros from different countries don't play each other enough to get a reliable international ranking (unlike tennis, where they all play each other in most tournaments).

I wish they would. I'd like to see frequent international tournaments, and also an international league (like team tennis, heh). Nongshim and Jeongganjang (now Huanglongshi) are so much fun.

Hmmm... pardon me, but I'm sceptical. Let's see...

Of 16 people there are 9 Koreans. Call them K1, K2...K9. There are 6 Chinese. Call them C1 thru C6. The Taiwanese we will call T1.

I start with T1. He gets a randomly chosen opponent, who happens to be Korean. There are 9 Koreans out of 15 possible opponents, so the odds are 3 out of 5.

Next, I'll take C1 and randomly pair him. There are 8 Ks left of 13 people. The odds that he gets a K are 8/13.

Next is C2. The odds that he gets a K are 7/11.

Then C3. His odds are 6/9 = 2/3.

For C4, the odds of a K are 5/7.

For C5, the odds are 4/5.

For C6, the odds are 1/1, for there are only Ks left.

The cumulative odds of all of this happening are 3/5 * 8/13 * 7/11 * 2/3 * 5/7 * 4/5 = 6720/75075 or slightly less than 9 percent.

Ok, it could be random.

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Let's not confuse meaningful low-probability events with meaningless low-probability events. In Feynman's case, the plate ARW 357 is no more significant than WEF 473, or any other plate. The particular plate has no more meaning than any other plate.
But suppose that John Wheeler's car had been stolen the day before, and its plate was ARW 357, and Feynman sees it in the parking lot. Then that plate is more meaningful than other plates.

In the LG cup pairing, about 9% of the possible pairings are meaningful in the context of avoiding same nationality pairings. And one of them occurred.

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BTW, it would have been a bit cleaner to refer to the 6 Chinese and 1 Taiwanese as simply non-Korean, ie: N1 through N7.

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The tables at Mr. Kin's site often reshuffle between rounds. At least some of the time, he does not know how future rounds are going to be paired.

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observation: the first round pairing had no avoidable in-country pairings. only one China-China, but that couldn't have been helped. also in the previous two years (i haven't checked further back) i couldn't find any avoidable in-country pairing. i won't compute the probabilities, but it doesn't look like a chance to me

worth noting is that this applies even for the first round, drawn randomly as we saw on the photos. possible explanation: divide the players in two groups of 16, one group from the most numerous nation (the Chinese here), the other with everyone else (plus randomly chosen Chinese over the number of 16), then issue two 1-16 sets of fans, one distribute in the first group, the other in the other

this is supported by the fact that as far as i can tell (i can't read Hangul and recognize only limited number of faces), if the Oro photos are shown in chronological or other logical order, there are first only the Chinese drawing numbers, then everyone else drawing numbers.

also it is nice system as at the same time balanced due to the pre-division and random, therefore fair

if i am correct, then it seems that the subsequent rounds are again paired randomly, with the same in-country avoiding criterion

is the system described in such a detailed way anywhere? i would imagine it should, at least in Korean. on the other hand, looking for ice-hockey WC format was not the easiest thing either, perhaps not everyone is as concerned with tournament systems as i am

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Spilling gasoline feels good.

I might be wrong, but probably not.

Yes, actually I noticed that when I went back to look, the initial table didn't agree with trout's 2nd round pairing. My mistake! So do they re-pair after each round? I'm really totally ignorant of how these things work. Also, I just missed Baduk TV's hour of LG coverage, arggh.

The tom.com site seems to show that the games start at 9:00 am on 6/20 (they show Lee Sedol's game, and Gu Li's then), which is 9:00 pm on the east coast of the U.S. tonight, Tuesday the 19th. I think Baduk TV will broadcast a game, or maybe cut between 2 games, but is there any place that has all the games? Do the online servers like KGS or IGS carry the games?

Sorry to ask dumb qns; just a newbie.

David, excellent idea to actually SHOW the Korean time on the TV guide page (and not write it's relationship to some other time zone), and to mark in red what is playing now. TV guides are supposed to make viewing easy, and yours does - good job!

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Patience, grasshopper.

ad go servers: yes, wbaduk.com has all or most of the games. possibly also tygembaduk.com relays some, never tried that one. i can recommend Asian servers very much for watching pro games, there are many of them

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Spilling gasoline feels good.

I might be wrong, but probably not.

Joaz, the point I was making was you calculated the probability of a particular event after that event had happened without declaring the event beforehand. Humans are very good at spotting patterns (indeed that helps us beat computers at Go!) and there are lots of other interesting patterns that could have happened in the draw which didn't happen and whose probability you didn't calculate. The probability of there being an interesting pattern is pretty high even if the probability of each one is quite low.

P.S not that I am saying they don't pair to mix countries, but using probabilities in that way is not rigourous.

no, you're in the exact right place.

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