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 Post subject: 10 year old Japanese pro
Post #1 Posted: Sat Jan 05, 2019 4:09 am 
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Younger than even Rina Fujisawa
https://www.japantimes.co.jp/news/2019/ ... yer-april/

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Post #2 Posted: Sat Jan 05, 2019 4:33 am 
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Perhaps the NHK TV tourney will need a seat adjustment. :tmbup:
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 Post subject: Re: 10 year old Japanese pro
Post #3 Posted: Sat Jan 05, 2019 7:35 am 
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Good to her. The Chinese have some very young pros (Wu Yimmin is around 11 if I remember correctly).
Does anybody know which one is she in this list: https://www.nihonkiin.or.jp/player/insei/joretu/index.html? You might have to go to the earlier months if she is not considered insei anymore after her promotion.

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Post #4 Posted: Sat Jan 05, 2019 9:32 am 
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silviu22 wrote:
Does anybody know which one is she in this list: https://www.nihonkiin.or.jp/player/insei/joretu/index.html? You might have to go to the earlier months if she is not considered insei anymore after her promotion.


Was she an insei, or did she become pro by a special recommendation rule, after playing some test game(s) with Cho U like the article suggests?

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 Post subject: Re: 10 year old Japanese pro
Post #5 Posted: Sat Jan 05, 2019 11:01 am 
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sorin wrote:
silviu22 wrote:
Does anybody know which one is she in this list: https://www.nihonkiin.or.jp/player/insei/joretu/index.html? You might have to go to the earlier months if she is not considered insei anymore after her promotion.


Was she an insei, or did she become pro by a special recommendation rule, after playing some test game(s) with Cho U like the article suggests?


I found Inseong's post here with more details: https://www.reddit.com/r/baduk/comments ... an/edb94ey
Looks like Nihon Ki-in has this new rule in an attempt to become more competitive on the international Go scene.

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 Post subject: Re: 10 year old Japanese pro
Post #6 Posted: Sat Jan 05, 2019 11:33 am 
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Sumire was selected as part of a new talent-spotting programme devised by the Nihon Ki-in.

The procedure is that at least two NK pros can nominate a candidate, who would normally be expected to be a primary school student. Then a panel of major title holders and national team coaches and board members scrutinise the nominee and make a recommendation based not just on current results but also on an assessment of future prospects. At least two thirds of the panel must favour appointment as pro for it to take effect (which as usual for new qualifications is the following first of April. Which means that as the new era name will be announced then, Sumire (which means Violet BTW) will also probably be the first pro under the new era. (Her birthday is 2 March.)

Sumire has been learning go since she was three. Her father Nakamura Shinya is a 9-dan in the Kansai (Osaka) Branch of the NK (not 5-dan as mistakenly given in the Japan Times article. Her mother Miyuki is a go instructor. Sumire would like to emulate Iyama Yuta, she said - Iyama of course also being a Kansai Branch player.

In other news from the NK, pro players are now required to deposit their mobile phones in a locker before playing games, and in the case of two-day title matches, each player has to go into lockdown with no means of communication overnight.

And for the Shibano Toramaru thread, he ended 2018 as the winner of prizes for most wins (46) and most games (69), both the for the second year in a row. But Fujita Akihiko 6-dan won the prize for best winning percentage (41-8; 83.7%). Koike Yoshihiro 3-dan won the prize for longest winning streak (19). Best female was Fujisawa Rina with a 43-23 record, the same as Ichiriki Ryo (and 43 wins is a record for a woman).

For comparison Iyama Yuta scored 35-26, though of course some were title wins! And worst of all, Cho Chikun scored 14-16, the first time since qualifying as a pro 51 years ago that he has had a negative score.

Although he didn't top any of the sections, Onishi Ryuhei 3-dan made a good showing in several, and so is also one to watch. The 6th Globis Cup is about to kick off, so another chance for Japan's under-20 players to show their mettle against international competition. Fujisawa Rina was their front-runner last year.


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 Post subject: Re: 10 year old Japanese pro
Post #7 Posted: Sat Jan 05, 2019 11:59 am 
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What isn't mentioned in that news report is that the girl has been trained in a Korean academy.

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 Post subject: Re: 10 year old Japanese pro
Post #8 Posted: Sat Jan 05, 2019 2:08 pm 
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John Fairbairn wrote:
Sumire has been learning go since she was three. Her father Nakamura Shinya is a 9-dan in the Kansai (Osaka) Branch of the NK (not 5-dan as mistakenly given in the Japan Times article. Her mother Miyuki is a go instructor. Sumire would like to emulate Iyama Yuta, she said - Iyama of course also being a Kansai Branch player.
Explains the 'Iyama vibes'... Who knows, she might win a title or two ;-).

John Fairbairn wrote:


And worst of all, Cho Chikun scored 14-16, the first time since qualifying as a pro 51 years ago that he has had a negative score.


Not that we need more evidence of his determination, but it took 51 years :).

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 Post subject: Re: 10 year old Japanese pro
Post #9 Posted: Sat Jan 05, 2019 7:59 pm 
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Macelee, the Japanese version of the article does describe in detail her training in South Korea. This includes, among others, her father's comment that the go (learning) environment is completely different, and he thought that he must have her study in South Korea if she is to have a shot in the international stage.

The Japanese go community has been in an sense of urgency since the turn of the century that we are slipping behind PRC and South Korea, and I believe this article intends to give another alarm on how we train promising kids. BTW, Fujisawa Rina, who currently holds the youngest age to become pro (age 11 and 6 months), was trained in Hong Dojo (located in Japan), run by a South Korean national and trained as South Korea Insei (currently 3p in Kansai Ki-in).

Below are the part of the article siting her training in South Korea.
プロ棋士の仲邑信也九段(45)と、囲碁の元インストラクターの幸(みゆき)さん(38)のひとりっ子。幸さんの手ほどきで3歳で碁を覚え、7歳から一家3人で韓国・ソウルに渡って修業。日本での義務教育履修のため日韓の往復生活を続けた。幸さんによると、菫さんはすぐに韓国語を覚え、両親の通訳にもなっているという。一昨年、現地の小学生低学年のチャンピオンに。昨年、韓国棋院のプロ候補生である研究生になった。
 韓国で“囲碁漬け”の日々を送ってきた。平日は名門「韓鐘振(ハンジョンジン)囲碁道場」で、週末は韓国棋院で対局を重ねてきた。現地のプロ志望の子どもたちは朝、学校に顔を出すとすぐに道場に向かい、夕方まで囲碁の勉強をする子が多い。
 「子どもたちの囲碁環境が日本と全く違う。あれを見て、菫が世界を狙うには韓国で勉強させなければと思った」と、父の信也九段が言う。根っからの負けず嫌いで、負けると大泣きする。その勝負魂が道場で高く評価されている。
 道場を主宰する韓鐘振九段は「菫の才能は、現在の女流世界一である韓国の崔精(チェジョン)九段(22)に劣らない。むしろ上達のスピードは崔より速い。このままいけば女流の世界チャンピオンになるのはもちろん、男性のトップ棋士とも対等に戦えると思う」と話す。


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 Post subject: Re: 10 year old Japanese pro
Post #10 Posted: Sun Jan 06, 2019 3:33 am 
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Details about Sumire are appearing piece-meal in the Japanese media, and not everything is clear as much of it is by and for people not really interested in go. It even made the BBC news over here!

As to her time in Korea, I'm not sure it is correct to say she has been trained in a Korean Academy since that (to me) sounds like she has effectively been produced by Korea. Maybe she has, but the other details don't seem to support that. For example, she apparently still goes to her primary school in Osaka (and finds combining an ordinary education with studying go very tough). I gather she went with her family to Seoul (she's an only child). The Japanese reports talk of going there and coming back repeatedly starting at age 7. I'm guessing that means she spent the summer holidays there, and by now that presumably means about three visits. At any rate, at the academy she has already picked up enough Korean to help interpret for her parents.

As to how strong she is, she played Iyama a year ago in an exhibition game in the Iyama Cup, a festival in Higashi-Osaka (Iyama's birthplace) on 2 stones. This week she played him there on Black, but the game was left unfinished as time ran out. In her trial game with Cho U she played taking Black with reverse komi. That suggests she may have improved a whole stone in the past year. At pro level that's astonishing.

It's not quite the same as when AlphaGo hit the scene, but still it's nice to have a bit of a buzz about a human for a change.

In that connection, as I was trawling through the Japanese reports I came across a recent story about an amateur 5-dan in Osaka who played Seto Taiki (a Kansai Ki-in 8-dan) in bed. But the twist was that Tanaka Hiroji has been bedridden since he was 7 (and is now 28, I think it was) with a muscle disease and is effectively paralysed. He can only communicate with his eyes, but has learned to convey his moves that way with some special apparatus (and human helper). I talked to a rehabilitation doctor about this ort of thing a few years ago, and saw some of the equipment in use (but not for go - just normal reading). it does seem quite remarkable, at both ends - the patient and the programmer.


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Post #11 Posted: Sun Jan 06, 2019 4:10 am 
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it does seem quite remarkable, at both ends - the patient and the programmer.
Yes. And Sir Stephen Hawking and Intel.

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 Post subject: Re: 10 year old Japanese pro
Post #12 Posted: Sun Jan 06, 2019 4:46 am 
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This appears to be the game between her and Iyama.



Ed: Stephen Hawking wasn't a Sir, he turned it down.


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 Post subject: Re: 10 year old Japanese pro
Post #13 Posted: Sun Jan 06, 2019 10:45 am 
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BBC article about this topic: https://www.bbc.com/news/world-asia-46773504

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 Post subject: Re: 10 year old Japanese pro
Post #14 Posted: Sun Jan 06, 2019 12:25 pm 
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The BBC news piece is good for promotion. But unfortunately they get the basic fact wrong.

According to Sensei's Library, in 1962 Cho Hunhyun "became the world's youngest pro at 9 years old via the Hankuk Kiwon".

Later the Chinese player Yang Dingxin (born in October 1998) passed the Chinese qualifying event in July 2008 to become professional. He was reported to be even younger.

There were other 9-year old professionals, such as Chang Hao (born 1976-11-07, becoming pro in 1986 - not sure the exact date, but Chinese promotion event were almost always held in summer).

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Post #15 Posted: Sun Jan 06, 2019 1:28 pm 
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You are probably right that the BBC report was sloppy. It looks like they just used the Kyodo agency story, which was written for a Japanese audience. But actually the way I read it was that Sumire would be the youngest pro in the world at the time she starts playing. In other words I think the normal native English locution for your meaning would probably be "youngest ever". But, yes, it was sloppy.

I have seen a source that Chang Hao was 10 when he became pro, and it seems there were also promotion games played at the year end in the early days. Also, he was taking 3 stones from Nie Weiping and Fujisawa Hideyuki in Spring 1986, so his must have zoomed up almost overnight later that year. But likewise I lack precise details.

Cho Hun-hyeon is an interesting case. Yes, he was 1-dan in Korea at age 9 but the following year, 1963, he moved to Japan and had to start at 4-kyu, not becoming 1-dan there until 1967.

I think Yang Dingxin can safely be called the "youngest ever" 1-dan. He became pro 1d at 9 years 9 months on 2008-07-24. His career since then has been surprisingly modest after such a stellar start, though he has notched up a few titles and is, of course, still only 20.

Historically Ogawa Doteki, 6-dan at age 13, in Japan and Huang Longshi, two stones to a guoshou at age 11, in China have already set a pretty impressive bar height. And for women, Yokozeki Iho was 1d at about age 15-16.

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Post #16 Posted: Sun Jan 06, 2019 10:52 pm 
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We might see a Japanese pro trained in Taiwan.

Did they start this system in just the last few months?

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Post #17 Posted: Mon Jan 07, 2019 5:16 am 
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And the guardian picked it up as well. I am impressed that so many western newspapers report on it.
https://www.theguardian.com/world/2019/ ... ofessional

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Post #18 Posted: Mon Jan 07, 2019 5:56 am 
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John Fairbairn wrote:
I think Yang Dingxin can safely be called the "youngest ever" 1-dan. He became pro 1d at 9 years 9 months on 2008-07-24. His career since then has been surprisingly modest after such a stellar start, though he has notched up a few titles and is, of course, still only 20.

He is doing well recently, got through to the final of the LG cup and will play Shi Yue in the final in February so has a decent chance to get his first international title, He's currently on a 9-game win streak (since November) and just got into the goratings top 10.

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Post #19 Posted: Mon Jan 07, 2019 3:26 pm 
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Some interesting discussion on Iyama's s12 peep, a common move from humans in this new joseki before sacrificing the 3 stones, which some versions of LeelaZero don't like over on facebook.

Here's my attempts at figuring out why LeelaZero #198 doesn't like it. First its suggested line for both (move 1 with 35k playouts, 10k at end). Some comments:
- 2 is one choice, cut is another but -3% now
- 4 is a nice tesuji, white is reluctant to atari at m18 because then after defending at L16 n13 works*
- 6 after making white make an ugly connection of 5 black's got some stones in sente which will be useful in making a mess on the top side later (compare to game where Iyama got m18 and made a big territory there)
- 7 gets good value out of losing the 3 stones, white can grow the middle later if that becomes big
White starts and ends this sequence with 59% (white then approaches at q5, in mainline white makes a group there, black then makes a group on top side, using k18 sente to help).

Click Here To Show Diagram Code
[go]$$Wc Dia 1
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . O . . . |
$$ | . . . . . . . . . 4 1 X . X . O X O . |
$$ | . . . O . . . . . , 5 O 2 . X X O O . |
$$ | . . . . . . . . . . . 3 9 O 0 O X X . |
$$ | . . . . . . . . . . . . 8 O 6 O O X . |
$$ | . . . . . . . . . . . 7 X X . X X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


* this is why n15 doesn't work without black tricking white into making black get a stone at n17:
Click Here To Show Diagram Code
[go]$$Wc Dia 1a
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . O . . . |
$$ | . . . . . . . . . . 1 X 8 X 9 O X O . |
$$ | . . . O . . . . . , . O 2 7 X X O O . |
$$ | . . . . . . . . . . . 3 4 O . O X X . |
$$ | . . . . . . . . . . . 6 5 O . O O X . |
$$ | . . . . . . . . . . . . X X . X X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]


If white peeps, the idea is white is going to sacrifice the 3 stones and then it's a good exchange as that one white stone could be helpful later in doing things on the right side (and it's not sente once 3 stones captured). However LZ 198 says it loses 10%, let's see what happens next.
- LZ says for 2 black won't n16 now (-7%) but will l16 crosscut instead
- white 3 at o16 is also good, but makes comparison harder to ignore that choice for now
- with 4 black trades, sacrificing the top for a ponnuki and sente
- the question is, is the marked exchange now good or bad?
White starts and ends this sequence with 49%.

Click Here To Show Diagram Code
[go]$$Wc Dia 2
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . 5 9 . . O . . . |
$$ | . . . . . . . . . . 1 8 3 X . O X O . |
$$ | . . . O . . . . . , 2 O 4 7 X X O O . |
$$ | . . . . . . . . . . . 6 . O . O X X . |
$$ | . . . . . . . . . . . . . O . O O X . |
$$ | . . . . . . . . . . . . X X . X X B . |
$$ | . . . . . . . . . . . . . . . . . W . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


Black could have chosen the crosscut if white didn't peep, but LZ thinks that's not so good. 2 lost 3%, so white ends this with 62%. The only difference between this diagram and the one above is the s12 s13 exchange.
Click Here To Show Diagram Code
[go]$$Wc Dia 3
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . 5 9 . . O . . . |
$$ | . . . . . . . . . . 1 8 3 X . O X O . |
$$ | . . . O . . . . . , 2 O 4 7 X X O O . |
$$ | . . . . . . . . . . . 6 . O . O X X a |
$$ | . . . . . . . . . . . . . O . O O X . |
$$ | . . . . . . . . . . . . X X . X X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


Is it really so bad? What's the difference?
- If the right side becomes black territory white lost 2 points vs playing endgame hane at a
- If white invades right side later then maybe she would peep at s12 anyway, but maybe not. You'd rather not pre-lose the points.
- Adds more liberties to q13 stones. It's kinda unlikely as terrible inside for outside exchanges, but say white wedged at p13 to create 2 cutting points, s12 actually means black can more easily answer on the outside with 4 and safely answer 5 at 6 as white can't s13 cut to capture the s14 stones (but white gets endgame squeeze, so black might actually atari under anyawy, depends on what's down the side, I'm just focusing on the local connectivity), without s12 maybe 4 would be at q11 and then there's a cutting point at o12 (probably used to peep as part of a reduction rather than to cut).

Click Here To Show Diagram Code
[go]$$Wc Dia 4
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . O O . . O . . . |
$$ | . . . . . . . . . . O X O X . O X O . |
$$ | . . . O . . . . . , X . X O X X O O . |
$$ | . . . . . . . . . . . X . O . O X X . |
$$ | . . . . . . . . . . . . . O 3 O O X . |
$$ | . . . . . . . . . . . . X X 1 X X X . |
$$ | . . . . . . . . . . . . . . 2 5 . O . |
$$ | . . . . . . . . . . . . . 4 . 6 . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


LZ 198 says yes, its -13% bad exchange, quite significant. You can even make the s12 exchange after the crosscut and ponnuki trade variation and see the same winrate drop. I guess it's mostly the chance of it ending up as mochikomi that causes the dislike. I like how LZ changed its answer to white l17 hane to turn s12 into a bad move instead of a good move, a common technique seen in high level probing play.

Edit: to further isolate the mochikomi aspect of the s12 s13 exchange I added some outside exchanges to make it more likely that right area will become a black territory so that the white peep won't be useful in a future invasion there (note this part of analysis is with <1k playouts). Starting from diagram 3 (black crosccuts for ponnuki, white hasn't peeped) it is black's move and he is at 38%. If I pass for black and allow white to reduce at 1 and have black answer at 2 and then pass for white to make it black to move again we now have black at 30%. So LZ thinks this is a good exchange for white (I thought it probably would be as black's answer seems soft, but I wasn't sure before checking with LZ as there is a downside of solidifying black). Note that neither of these moves are the best if they had a free choice, LZ 198 says approach (for 1) or enclose (for 2) at q5 is best. The purpose is to create a somewhat realistic whole board position in which LZ will think the right side is black territory (and also means p13 no longer creates 2 cutting points). o11 to q8 is a bad shape so I add another reducing exchange of 3-4 that's also slightly helping white: black is now down to 27-28% (LZ thinks black's best next move is either q5: very normal, or interestingly n5: weird shape to be 5th line, n4 is what I would expect if trying to be more ambitious than solid shimari). Then to try to get black's winrate back up closer to the 38% original I make the peep-connect exchange of 5-6 in reverse, in hypothetical play probably peep of 6 would come before defending with 4, though really if black attempted to peep there first LZ says white should just ignore and q5 approach. This makes white heavier and gets black an outside stone so now his winrate is up to 31% (with suggested next move at q5 again).
Click Here To Show Diagram Code
[go]$$Wc Dia 5
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . O O . . O . . . |
$$ | . . . . . . . . . . O X O X . O X O . |
$$ | . . . O . . . . . , X . X O X X O O . |
$$ | . . . . . . . . . . . X . O . O X X . |
$$ | . . . . . . . . . . . . . O . O O X . |
$$ | . . . . . . . . . . . . X X . X X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . 1 . 2 . . . . . |
$$ | . . . , . . . . . , 6 5 . . . , . . . |
$$ | . . . . . . . . . . . 3 . 4 . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]

So with the setting prepared, what difference to winrate does it make if we make the s12 s13 exchange? Answer: black is up to 53% (again q5 next move), so 22% mistake now instead of 13% when it's more even likely to be mochikomi. Having said that, LZ as white still wants to tease black's right side: after q5 enclose it wants to r7 invade and then just leave it for aji.
Click Here To Show Diagram Code
[go]$$Wc Dia 6 Black's move and ends at 53%
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . O O . . O . . . |
$$ | . . . . . . . . . . O X O X . O X O . |
$$ | . . . O . . . . . , X . X O X X O O . |
$$ | . . . . . . . . . . . X . O . O X X . |
$$ | . . . . . . . . . . . . . O . O O X . |
$$ | . . . . . . . . . . . . X X . X X 2 . |
$$ | . . . . . . . . . . . . . . . . . 1 . |
$$ | . . . . . . . . . . . O . X . . . . . |
$$ | . . . , . . . . . , X O . . . , . . . |
$$ | . . . . . . . . . . . O . X . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]

For completeness, what if white makes the endgame exchange? This is premature (losing a ko threat and the peep aji if an invasion did still happen) so loses some winrate for white, but isn't as bad as giving black 2 points and black ends at 42%, so white lost 11%. (Black's next move either q5 or n4 or n5 or m6 or m5 (#1 after a few k playouts)).
Click Here To Show Diagram Code
[go]$$Wc Dia 7 Black's move and ends at 42%
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . O O . . O . . . |
$$ | . . . . . . . . . . O X O X . O X O . |
$$ | . . . O . . . . . , X . X O X X O O . |
$$ | . . . . . . . . . . . X . O . O X X 1 |
$$ | . . . . . . . . . . . . . O . O O X . |
$$ | . . . . . . . . . . . . X X . X X 2 . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . O . X . . . . . |
$$ | . . . , . . . . . , X O . . . , . . . |
$$ | . . . . . . . . . . . O . X . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]


This post by Uberdude was liked by 4 people: Bill Spight, Elom, gamesorry, johnsmith
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 Post subject: Re: 10 year old Japanese pro
Post #20 Posted: Tue Jan 08, 2019 1:40 pm 
Dies with sente

Posts: 118
Liked others: 34
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Rank: KGS 6 dan
This analysis was so good. Very profesional mix of LZ opinion + human rationale. Please keep them coming.


This post by johnsmith was liked by: Uberdude
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