Life In 19x19

mhlepore wrote:Can someone explain the Lin Lixiang - Na Hyun game? I don't see how black is alive after he makes his final move in the corner, yet white resigned immediately thereafter. Blind spot? What am I missing?

Thanks.

My impression is that the move not only forces White to play the killing move, but it makes the corner a semedori for White to have to spend several stones to capture the group. So White not only has to fill inside his own territory eventually, but Black can make some nice endgame sequences from the outside to gain even more out of it. This may just be too much of a disadvantage for White to overcome.

I found the Hane Naoki - Eric Lui game interesting with its big moyo posing several tricky positional judgement problems. Eric played black and went for centre infleunce when Hane approach the top, then switched to a territorial move with enclosing the lower right and next expanding the lower side and preventing white's shoulder hit at a.

Click Here To Show Diagram Code

[go]$$Wcm22
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . 3 . . . |
$$ | . . . . . O . . . . . . . 1 . . 5 . . |
$$ | . . . O . . . . . , . . . . . X . . . |
$$ | . . O . . O . . . . . . 4 . . . . . . |
$$ | . . X X . . . . . . . . . . . 2 . . . |
$$ | . . . . . 7 . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X . . X . . . . . . . . . . . . . |
$$ | . O . , . . . . . , . . . . . , . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X O . . . . . 8 . . . . . . X . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . O , X . . . . a . . . . . X . . . |
$$ | . . . O X . . . X . . . . . 6 . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]

struck me as somewhat inconsistent with the moyo plan, though it is undeniably a huge move and works well with next. However, when watching the game my eye was drawn to the following. I liked this move for its large scale connectivity of the 2 marked black stones, and for preventing black's top left group becoming weak. It's a pretty unconventional opening move, being a 6th line shoulder hit (maybe AlphaGo or Takeymiya style?!), but I think black is happy to build the wall if white pushes at b-g etc. (I would not expected white to push but tenuki) as black's potential in the centre looks better than white's top side, which still has a hole in at h. The fact that Hane played his next move in this area, at a, which is a quiet but powerful influence point made me think my idea might not have actually been so crazy after all. What do others think? Is it a good move? Better than Eric's? Or some vague dame rubbish?

Click Here To Show Diagram Code

[go]$$Bcm27
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . O . . . |
$$ | . . . . . O . . . . . . h O . . O . . |
$$ | . . . O . . . . . , . . . . . X . . . |
$$ | . . O . . O b d f . . . # . . . . . . |
$$ | . . X X . . 1 c e g . . . . . X . . . |
$$ | . . . . . a . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X . . # . . . . . . . . . . . . . |
$$ | . O . , . . . . . , . . . . . , . . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X O . . . . . . . . . . . . X . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . O , X . . . . , . . . . . X . . . |
$$ | . . . O X . . . X . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]

When Hane invaded high on the right side, Eric played a shoulder hit which grew the lower side, but at the expense of weakening his top group and his moyo on the top side disappeared and turned into a weakish group, so I didn't like this for black (note the interesting technique of atari and then hanging connection which one might think of as bad style (helping opponent extend where he wants to), but here the solid extension would leave the vital point peep of q11 behind). I'm not sure what would be better, but my feeling was this problem arose from the inconsistency of going for a large-scale central moyo with but then switching to a smaller-scale lower side moyo with and .

Click Here To Show Diagram Code

[go]$$Wcm30
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . O . . . |
$$ | . . . . . O . . . . . . d O . . O . . |
$$ | . . . O . . . . . , . . . . . X . . . |
$$ | . . O . . O . . . . . . X . . . . . . |
$$ | . . X X . . . . . . . . . . . X . . . |
$$ | . . . . . O . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X . . X . . . . . . a . c . . . . |
$$ | . O . , . . . . . , . b 8 7 . , . . . |
$$ | . . . O . . . . . . . . 9 4 3 1 . . . |
$$ | . . . . . . . . . . . . . 0 2 5 . . . |
$$ | . . . . . . . . . . . . . . 6 . . . . |
$$ | . . X O . . . . . X . . . . . . X . . |
$$ | . . . O . . . . . . . . . . . . . . . |
$$ | . . O , X . . . . , . . . . . X . . . |
$$ | . . . O X . . . X . . . . . X . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]

Round of 16;

Kono Rin defeated Park Yeonghun by resign.
Ke Jie defeated Wang Yuanjun by 0.5.
Kim Jiseok defeated Mi Yuting by resign. ** What a game !! Lot of Ko !!!!!!!
Lee Sedol defeated Lin Lixiang by resign.
Kang Dongyun defeated Won Seongjin by resign.
Park Junghwan defeated Huang Yunsong by resign.
Tang Weixing defeated Hane Naoki by 3.
Shi Yue defeated Fan Tingyu by 1.


**** Myoungwan Kim 9p will broadcast Ing cup this Saturday.
http://www.usgo.org/news/2016/04/myungw ... -saturday/

Pairing for round of 8 -4/24 ;
Shi Yue vs Kono Rin
Kim Jiseok vs Tang Weixing
Kang Dongyoon vs Lee Sedol
Ke Jie vs Park Junghwan

Poor Huang Yunsong - he played an opening that Park Junghwan played 2 years ago and must have lots of experiences with. (http://www.go4go.net/go/games/sgfview/43328 http://www.go4go.net/go/games/sgfview/53678) In fact the two games are so similar, that it actually fails the so-called Dyer's Signature that uniquely identify SGF game records. My back-end system told me that I were attempting to input a duplicate game to the database.

The game of epic ko between Kim Jiseok and Mi Yuting:

So again Kono Rin pulls an upset (27% win chance vs Park, versus 35% vs Chen according to Remi's goratings). For me the crucial moment was Park's move 1 below, threatening to cut. I don't really understand this move, did he expect Kono to passively connect on dame in gote? In the game Kono resisted by extending outwards, and when Park cut Kono connected on the first line (which itself has some endgame value, maybe Park would like to cut there (which give him sente hane-connect against the corner) and force white to connect) and settled his cut group in the centre fairly easily and profitably, eventually surrounding some centre points with a and forcing black to connect miserably himself with b.

Click Here To Show Diagram Code

[go]$$B
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . . . . . . . X X O . |
$$ | . . O . . X . . X X . . . . . X O . . |
$$ | . . . O . . . . . O X . . . . X O . . |
$$ | . . . . . X . . . . . . . . . X O . . |
$$ | . . O . . . . . . . . . . . X O O . . |
$$ | . . . . . . . . . O . . . X X X X O O |
$$ | . . . . . O . . . . . . . . O . . X . |
$$ | . O O O . . . . . . . . . . . . X . . |
$$ | . X O X X . . . . , . . . . . O O . . |
$$ | . . X . . . . . 2 . . . . . . . . . . |
$$ | . . . . X . . X O . . a . . . . . . . |
$$ | . . X . . . . X O . . . . . O . O . . |
$$ | . . X O . . X O 4 . . X . . . . . . . |
$$ | . O O . O X 1 3 O X . X O O . . . . . |
$$ | . . . , O X . O 5 X . . . X O , X . . |
$$ | . . . O X X . . O X . O O O X X . . . |
$$ | . . . O . . . O . . X . b X O X . . . |
$$ | . . . . 6 . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]

I suppose all this arose because of Kono's sharp invasion here:

Click Here To Show Diagram Code

[go]$$W
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . . . . . . . X X O . |
$$ | . . O . . X . . X X . . . . . X O . . |
$$ | . . . O . . . . . O X . . . . X O . . |
$$ | . . . . . X . . . . . . . . . X O . . |
$$ | . . O . . . . . . . . . . . X O O . . |
$$ | . . . . . . . . . O . . . X X X X O O |
$$ | . . . . . O . . . . . . . . O . . X . |
$$ | . O O O . . . . . . . . . . . . X . . |
$$ | . X O X X . . . . , . . . . . O O . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . X . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . O . O . . |
$$ | . . X O . . X . . . . X . . . . . . . |
$$ | . O O . O 4 . . . . . X O O . . . . . |
$$ | . . . , O X . 3 . X . . . X O , X . . |
$$ | . . . O X X . . 1 2 . O O O X X . . . |
$$ | . . . O . . . 5 . . . . . X O X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]

Park did also play some nice endgame in the top right corner to remember (if you want more profit at the expense of sente):

Click Here To Show Diagram Code

[go]$$Bc
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . 9 6 . |
$$ | . . O X . . . . . . . . . . . X X O 5 |
$$ | . . O . . X . X X X . . . . . X O 7 3 |
$$ | . . . O . . . O . O X . . . . X O 4 . |
$$ | . . . . . X . . . . . . . . . X O 2 1 |
$$ | . . O . . . . O . . X X X . X O O . 8 |
$$ | . . . . . . X O . O O O O X X X X O O |
$$ | . . . . . O X O X . . O X X O . . X . |
$$ | . O O O . . X X O X . . O . . . X . . |
$$ | . X O X X . X O O , . . . . . O O . . |
$$ | . . X . . X O O O . . . . . . . . . . |
$$ | . . . . X . O X O . . O . . . . . . . |
$$ | . . X X . X X X O . . . . . O O O . . |
$$ | . . X O O . X O O . . X . . . X . . . |
$$ | . O O . O X X X O X . X O O . . . . . |
$$ | . . . , O X . O X X . . . X O , X . . |
$$ | . . . O X X . . O X . O O O X X . . . |
$$ | . . . O . . . O . . X . X X O X . . . |
$$ | . . . . O . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]

macelee wrote:In fact the two games are so similar, that it actually fails the so-called Dyer's Signature that uniquely identify SGF game records.

Nice. I added this example to http://www.cwi.nl/~aeb/go/misc/signatures.html. Clearly, games that coincide in their first 71 moves will have the same Dyer signature. Here, the games only agree for 62 moves, and happen to have the same move 71.

Uberdude wrote:
Park did also play some nice endgame in the top right corner to remember (if you want more profit at the expense of sente):

$$B
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . 9 6 . |
$$ | . . O X . . . . . . . . . . . X X O 5 |
$$ | . . O . c X . X X X . . . . . X O 7 3 |
$$ | . . . O . . . O . O X . . . . X O 4 . |
$$ | . . . . . X . . . . . . . . . X O 2 1 |
$$ | . . O . . . . O . . X X X . X O O . 8 |
$$ | . . . . . . X O . O O O O X X X X O O |
$$ | . . . . . O X O X . . O X X O . . X a |
$$ | . O O O . . X X O X . . O . . . X . . |
$$ | . X O X X . X O O , . . . . . O O . . |
$$ | . . X . . X O O O . . . . . . . . . . |
$$ | . . . . X . O X O . . O . . . . . . . |
$$ | . . X X . X X X O . . . . . O O O . . |
$$ | . . X O O . X O O . . X . . . X . b . |
$$ | . O O . O X X X O X . X O O . . . . . |
$$ | . . . , O X . O X X . . . X O , X . . |
$$ | . . . O X X . . O X . O O O X X . . . |
$$ | . . . O . . . O . . X . X X O X . . . |
$$ | . . . . O . . . . . . . . . . . . . . |
$$ +---------------------------------------+

Click Here To Show Diagram Code

[go]$$B
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . 9 6 . |
$$ | . . O X . . . . . . . . . . . X X O 5 |
$$ | . . O . c X . X X X . . . . . X O 7 3 |
$$ | . . . O . . . O . O X . . . . X O 4 . |
$$ | . . . . . X . . . . . . . . . X O 2 1 |
$$ | . . O . . . . O . . X X X . X O O . 8 |
$$ | . . . . . . X O . O O O O X X X X O O |
$$ | . . . . . O X O X . . O X X O . . X a |
$$ | . O O O . . X X O X . . O . . . X . . |
$$ | . X O X X . X O O , . . . . . O O . . |
$$ | . . X . . X O O O . . . . . . . . . . |
$$ | . . . . X . O X O . . O . . . . . . . |
$$ | . . X X . X X X O . . . . . O O O . . |
$$ | . . X O O . X O O . . X . . . X . b . |
$$ | . O O . O X X X O X . X O O . . . . . |
$$ | . . . , O X . O X X . . . X O , X . . |
$$ | . . . O X X . . O X . O O O X X . . . |
$$ | . . . O . . . O . . X . X X O X . . . |
$$ | . . . . O . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]

Uberdude, it is good to know this technique. However do you really think that it did any good in this game?

The simple 2-1 sente move leaves white with 6 points. The real sequence: white had 3 points, black got 4 extra. So the difference is 7 points. However, blocking at 'a' is no longer a sente move for black. So black's gain seems really limited (more like 6 points). I think there are still other big yose, such as 'b' and 'c'. 'c' is very large (>10 points).

macelee wrote: However do you really think that it did any good in this game?

Not particularly. I was just highlighting a possible endgame tesuji that probably I would find in a go problem but miss in a game because it is not internalised as part of my (and presumably some other readers') Go vocabulary.

Actually the thing that interested most in the endgame was the timing of when Kono played c18, rather than o12 which I thought he would from his previous moves. Park then played o12 (in sente!) and broke into some of that centre potential, but Kono kept some around the k10 area. My understanding of this was that Kono didn't want to build such a big centre because then he would be somewhat obliged to answer n7 at n8, but then o7 o8 and p6 and black cuts off and captures a load of white stones. So he went for the simple huge c18. That meant Park never got to save the q6 stone which was pretty big with the cutting aji it creates with n7. It seems like black played too many gotes with s10 and p10, maybe s10 should have been r6 as coupled with n7 that means black has a way into the centre?

Maybe he didn't want to answer at c because that means white got the good exchange of the corner block in sente, and fighting spirit prompted him to do something else, even if that something else is objectively smaller. I certainly suffer from this thinking sometimes.

Another endgame issue, it feels very un-honte and thin, but how about this strange answer to prevent the clamp capture of the single stone if white next blocks in the corner? Does it gain more points in the e18 area than it loses around h17? My instinct without careful counting is yes (black can also b18 next). I presume the reason Kono did that peep(?) before blocking the corner was precisely because if he did later clamp it would no longer be forcing.

Click Here To Show Diagram Code

[go]$$Wc
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . 2 . . . . . . . . . X X O . |
$$ | . . O . . X . . X X . . . . . X O . . |
$$ | . . . O . . . 1 . O X . . . . X O . . |
$$ | . . . . . X . . . . . . . . . X O . . |
$$ | . . O . . . . O . . X X X . X O O . . |
$$ | . . . . . . X O . O O O O X X X X O O |[/go]

Round 2 produced a lot of close, exciting games. What a treat! I expect round 3 will be good, too; there are a lot of good match-ups. It's hard to have a bad one when all but one player (Kono Rin) is in the top 15 on goratings.org. Kono's somewhat unexpected run in the tournament is a nice treat for anyone who likes to root for the underdog and/or Japanese go.

Quote from Lee Sedol, "동윤이도 힘든데 정환-커제까지, 낙이 없네" Even Dongyoon is difficult openent and the next either Park Jungjwan or Ke Jie. No way(while laughing).....

Round of 8;
Shi Yue defeated Kono Rin by resign.
Lee Sedol defeated Kang Dongyoon by 5.
Park Junghwan defeated Ke Jie by 1. Park was penalized 2 points for taking extra time.
Tang Weixing defeated Kim Jiseok by resign.

Semi Final(3 games match, 6/10, 6/12, and 6/14),
Lee Sedol vs Park Junghwan
Shi yue vs Tang Weixing

Nailbiting stuff in the Ke - Park game. Park (white) came out of the opening and first rounds of fighting with a territorial lead, and Ke faced a difficult task of enclosing endough (~15) points in the centre to make the game even. Park played several safe but perhaps slightly slack moves and it seemed Ke managed to pull ahead. At one point Myungwan Kim said it was now nearly impossible for Ke to lose, only 5% chance for Park to catch up, but Ke played a mistimed small rather than large knight's move on the left edge that Park ignored to reduce the centre, and in the following trades (involding ko) that followed Ke lost a few points, and Park ended up several points ahead so could even afford to give the 2 points penalty. I'm glad that penalty didn't change the game result, that would be awkward!



Also I think Lee Sedol will be happy with that result, he has a good record against Park (17 wins to 11 loses) despite being lower in the Korean and Remi's ratings, whereas Ke Jie has a big edge on Lee (8 wins, 2 loses). So I'm now rooting for Lee Sedol to win it (which would be nice for him after the AlphaGo match).

trout wrote:Round of 8;
Shi Yue defeated Kono Rin by resign.
Lee Sedol defeated Kang Dongyoon by 5.
Park Junghwan defeated Ke Jie by 1. Park was penalized 2 points for taking extra time.
Tang Weixing defeated Kim Jiseok by resign.

Semi Final(3 games match, 6/10, 6/12, and 6/14),
Lee Sedol vs Park Junghwan
Kono Rin vs Tang Weixing

Why the 3 game match system let Kono Rin play in four final player match?