Learning from the Master

Uberdude · Post by **Uberdude** » Mon May 08, 2017 7:54 am

Revilo wrote:
Uberdude wrote:
[2017-05-07] 1st ENN Cup, round 4
Zhou Ruiyang 9p (Black) vs. Shin Jinseo 8p (White) B+R
... Black seems to have taken a very close look at AlphaGo's games.

Indeed, Zhou Ruiyang was one of the 9p analysts for the Deepmind commentaries on the Lee Sedol and self-play games, so maybe he even got to see some inside stuff others didn't. He has also played the attachment into the Chinese opening like AlphaGo did in the self-play game a few times: http://www.lifein19x19.com/forum/viewto ... 33#p215933 (and link in following post).

P.S. the ending of that game was strange. Shin seemingly blundered and played his own ko threat without answering Zhou's larger one and retaking the ko first (as Bei Ge did in a British Championship match a few years ago), but I think he was losing anyway (Bei wasn't).

Revilo · Post by **Revilo** » Mon May 08, 2017 8:49 am

Uberdude wrote:
Revilo wrote:
Uberdude wrote:
P.S. the ending of that game was strange. Shin seemingly blundered and played his own ko threat without answering Zhou's larger one and retaking the ko first

Are you referring to White 298 (K13)? I obviously don't have much of a clue but doesn't this seem like "Looking for a place to resign"? Black seems ahead (I haven't counted exactly) and White just plays the last cheapo, hoping Black mechanically retakes the ko so that White can take the stones in the centre, and that he resigned immediately after Black had followed through on his own ko threat?

Uberdude · Post by **Uberdude** » Mon May 08, 2017 9:33 am

Revilo wrote: Are you referring to White 298 (K13)? I obviously don't have much of a clue but doesn't this seem like "Looking for a place to resign"? Black seems ahead (I haven't counted exactly) and White just plays the last cheapo, hoping Black mechanically retakes the ko so that White can take the stones in the centre, and that he resigned immediately after Black had followed through on his own ko threat?

Yes. It could be looking for a place to resign by seppuku, but it's a bit weird. Your proposed strategy doesn't work though because even if black retook the ko, white capture 4 stones in middle black would at least then surely realise white didn't answer his threat so then kill that group which was far bigger than the 4 stones. A video to see body language would help here.

Uberdude · Post by **Uberdude** » Tue May 09, 2017 7:19 am

More Master-esque play from Ke Jie (black) and Li Zhe in the ENN cup 5th round:

Attaching into micro Chinese opening like Master game #1 (human in that game played hane in corner).

Click Here To Show Diagram Code: [go]$$W $$ +---------------------------------------+ $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . X . . . . . X . . . . . . . | $$ | . . . O . . . . . , . . . . . 1 X . . | $$ | . . . . . . . . . . . . . . . . 2 . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , O . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O O . . | $$ | . . . . . . . . . . . . . . . O X . . | $$ | . . . O . . . . . , . . . . . O X . . | $$ | . . . . . . . . . . . . . X . X X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ +---------------------------------------+[/go]

This isn't a Master move and is sometime thought of as a trick, though iirc Ichiriki used it in a big match in Japan:

Click Here To Show Diagram Code: [go]$$B $$ +---------------------------------------+ $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . 1 . . . . . . . . . . . . . . . . | $$ | . . . . . X . . . . . X . . . . . . . | $$ | . . . O . . . . . , . . . . . O X . . | $$ | . . . . . . . . . . . . . . . . X . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . O O O X . | $$ | . . . . . . . . . . . . . . O X X . . | $$ | . . . . . . . . . . . . . . . . . X . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . O O . . | $$ | . . . . . . . . . . . . O . . O X . . | $$ | . . . O . . . . . , . . . . . O X . . | $$ | . . . . . . . . . . . . . X . X X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ +---------------------------------------+[/go]

Not Master-esque, but I like the shape tesuji 1-3 combo from Ke. And then early 3-3 for 9.

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

oren · Post by **oren** » Tue May 09, 2017 11:12 am

Uberdude wrote: This isn't a Master move and is sometime thought of as a trick, though iirc Ichiriki used it in a big match in Japan:

Ida played it in a Honinbo match is the event I think you're talking about.

Uberdude · Post by **Uberdude** » Fri May 12, 2017 4:27 am

Following Peng Liyao 6p beating Zhou Ruiyang 9p in the semi-final of the ENN/Xinao cup with a new move for white in what I'm calling the "Master orthodox opening" (Michael Redmond calls it 'Master's favourite opening" in his reviews) I thought I'd analyse it in detail with help from my merged Master's games sgf. The "orthodox opening" normally means a black 4-4 plus facing small shimari without caring about the white corners, but for this I mean the following whole board position:

Click Here To Show Diagram Code: [go]$$B Dia. 1 $$ +---------------------------------------+ $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . 2 . . . . . , . . . . . 1 . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , 3 . . | $$ | . . . 4 . . . . . . . . . 5 . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ +---------------------------------------+[/go]

Master played this as black 13 times in its 60 games and played against it as white 5 times.

As an aside, it's worth noting that if white 4 is at 4-4 as below Master doesn't play the big low shimari but always the big high at 5, which it did so 4 times, once exchanging a for b first (and if white answers with 6 at a as the humans did twice (Ke Jie and Gu Zihao) then Master played shoulder hit at c both times). I understand this as the 4-4 making the lower side a more interesting area for both (for starters black can approach the 4-4 from that side, but not the 3-4), so Master plays high to increase the development potential on that side which offers white the choice: either play a solid but slightly slow shimari there which I can efficiently shoulder hit, or if you go into the right side I get to play first on the lower side and a high shimari is then better.

Click Here To Show Diagram Code: [go]$$B Dia. 2 $$ +---------------------------------------+ $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . 2 . . . . . , . . . . . 1 . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . b . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . 4 . . c . . , . . . 5 . , 3 . . | $$ | . . . . . a . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ +---------------------------------------+[/go]

Anyway, how to continue in the Master orthodox opening? The continuations from the 60 games are marked below. In all cases the humans played on the right side of the board: wedge at a was played by humans 3 times, inside approach at b 7 times (bit more modern/active than wedge), outside approach at c once (by Nie Weiping). On the other hand Master never played on the right but always made its own shimari: 4 times small high at d and once small low at e (in this case the game was upside down which I wouldn't expect to make a difference, but coincidence?). This is very significant difference in direction and suggests our opening theory could be misguided. Master seems to be saying it's fine to allow black to take the very nice opening point in the middle of the right side (simultaneous extension from shimari and 4-4) or a shimari from the 4-4 (tighter modern style), I'll just go my own way and build my own thing too, thank you very much. Perhaps this is because the komi is large (Master/AlphaGo apparently slightly prefers white on an empty board)? Given (mostly as black) how much it likes to low approach its opponent's 3-4 points, it seems it places a very high value on preventing that as white in this opening.

Click Here To Show Diagram Code: [go]$$B Dia.3 $$ +---------------------------------------+ $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . c . . . . . | $$ | . . . O . . . . . , . . . . . X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . b . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , a . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . e d . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , X . . | $$ | . . . O . . . . . . . . . X . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ +---------------------------------------+[/go]

If white approaches the top right (squared white stone below) Master always answers with the knight's move (black square, 7 games). White sometimes then slides (a, 2 games) or extends to the middle of the side on the 3rd line (5 games). Master then always low approaches the bottom left. In the 2 games where white humans slid, they then took the 3-3 (b) and Master ignored again to play on the left. This could be seen as fighting spirit: we humans think of the slide as a big move, threatening to play the 3-3 which is the mutual base point so semi-sente (local answer for black is to extend at c to make a base and prevent white attacking around there). However, I suspect taking the 3-3 is slow: the shape is weak (the slide at a would be better placed one space to the left, you can tewari approaching a 3-3 stone) so it is not actually so easy to attack the black group: in both of the games Master didn't defend but played big moves elsewhere and then the humans tried to attack but failed to get a good result (#6 Li Xingyu and #24 Park Junghwan with the famous 2nd line crawl from Master). Consequently I think the slide is not a good move, as its threatened follow-up of the 3-3 doesn't seem so severe when ignored, this view is reinforced by the fact Master never (iirc) played the slide in the 60 games. So if white extends we end up with a similar position to if white simply wedged (3 games), but with the exchange of the squared stones (5 games). Master then low approaches the bottom left and in all but 1 of the games the human played the 3 space pincer (humans like the relationship of this with the 4-4) (the exception was with the wedge only, and the 'pincer' was one space further away). How Master continues depends on whether the squared exchange was made: if not then it plays the knight's press (2 games), if it was then the large taisha press (5 games). Michael Redmond talked about this in his recent video on Li Qincheng's game (wedge only).

Click Here To Show Diagram Code: [go]$$B Dia. 4: Master plays d if no squared stones, e if squared stones exchanged $$ +---------------------------------------+ $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . c . . # . . b . . | $$ | . . . O . . . . . , . . . . . X . a . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . @ . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , O . . | $$ | . . 2 . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . 1 . . . . . . . . . . . . . . . . | $$ | . . . , d e . . . , . . . . . , X . . | $$ | . . . O . . . . . . . . . X . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ +---------------------------------------+[/go]

Before trying to understand why this exchange makes a difference to which press Master plays, let's look at a typical continuation. With the knight's press (2 games) it ends up as below. In one game the human (Li Qincheng) played low for 8 and Master played shoulder hit for 9, in the other they played high and Master made a base with 9 on 3rd line. I can see some logic to this change: if white is low black has more centre potential (can shoulder hit at a) so it makes sense to go for a direction in which you might end up with a centre wall (Redmond showed some variations with this), if white is high the black group is under more pressure so Master plays more conservatively to make a base.

Click Here To Show Diagram Code: [go]$$B Dia. 5: Continuation after knight's press (no top right exchange); 2 games $$ +---------------------------------------+ $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . 8 . . . . . . . . . . . . . | $$ | . . . O . 8 a . . , . . . . . X . . . | $$ | . . 6 . . . . . . . . . . . . . . . . | $$ | . . 5 7 . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . 9 . . . . . . . . . . . . . . . . | $$ | . . . 9 . . . . . , . . . . . , O . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . X . . . . . . . . . . . . . . . . | $$ | . . . , 1 3 . . . , . . . . . , X . . | $$ | . . . O 2 . 4 . . . . . . X . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ +---------------------------------------+[/go]

With the taisha press the humans avoid the complicated taisha line and all 5 games proceeded as below. The normal joseki is then to jump to a and one human (#27 Fan Tingyu) did so. The problem with this is it is gote and black can then counter pincer white 2 having built up the wall as some strength in sente. So in the other 4 games the humans crawled one more time, hoping black would extend and then they could play on the left side (e.g. b which develops corner and extends a helping hand to the pincer stone such that with a black invasion between them it's black who is the weaker one). If you crawl 4 times and black extends then the black covering turn on the lower side is not so powerful on the corner group, e.g. c is not sente (Redmond talked about this in an older video).

Click Here To Show Diagram Code: [go]$$B Dia. 6: Continuation after taisha press (top right exchanged); 5 games $$ +---------------------------------------+ $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . X . . . . . | $$ | . . . O . . . . . , . . . . . X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . b . . . . . . . . . . . . . O . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , O . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . X . 3 . . . . . . . . . . . . . . | $$ | . . . , 2 1 5 7 9 , . . . . . , X . . | $$ | . c . O . 4 6 8 . a . . . X . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ +---------------------------------------+[/go]

Of course Master is aware (as far as an AI is!) that extending after the 4th crawl is slack, so immediately counter-pincers even though there is a locally urgent hane-at-the-head situation. In 2 of the games (#7, #9 Meng Tailing) the human immediately hanes and we get rather different results, but in the other 2 (#5, #28 Meng again) and Fan's jump we get very similar results as show below. Next Master extends to b/c on the top (aiming at d next) which develops the top side and gently reduces the influence of the white thickness and in the future could even ask questions about how alive it is (in game #5 Master killed it). This pattern of giving walls and then reducing their influence crops up many times in Master's games, such as with the push through the table shape in the magic sword joseki. In Fan's game he immediately defended at d, in the other 2 with the push on the lower side they played the urgent-looking liberty-taking hane at the lower side hoshi. During this sequence Master's slide of 5, allowing the seal at 6, is an interesting move. Professionals have played it before, but the jump out to 6 is more common. Master hitting the shape point at 7 seems to be a new move, though the similar idea at d has been played before.

Click Here To Show Diagram Code: [go]$$B Dia. 7: Continuation after taisha press part 2; 3 games (in 1 game white squared stone at a) $$ +---------------------------------------+ $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . d . . . . . . . X . . . . . | $$ | . 5 . O 0 7 . . b c . . . . . X . . . | $$ | . . 9 . . . . . . . . . . . . . . . . | $$ | . . 3 8 6 . . . . . . . . . . . O . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . 1 . 4 . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , O . . | $$ | . . O . 2 . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . X . X . . . . . . . . . . . . . . | $$ | . . . , O X X X X , . . . . . , X . . | $$ | . . . O . O O O @ a . . . X . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ +---------------------------------------+[/go]

So what difference does the exchange at the top right make to these results? Michael Redmond has a hypothesis that with the exchange a ladder in a taisha variation that was good for white becomes good for black, so black is happier to taisha:

Click Here To Show Diagram Code: [go]$$B Dia. 8: Redmond's taisha ladder, part 1 $$ +---------------------------------------+ $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . X . . . . . | $$ | . . . O . . . . . , . . . . . X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . O . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , O . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . 8 . . . . . . . . . . . . . . . | $$ | . . X 2 7 . . . . . . . . . . . . . . | $$ | . . 5 3 4 1 . . . , . . . . . , X . . | $$ | . . 9 O 6 0 . . . . . . . X . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ +---------------------------------------+[/go]

The normal joseki is to play 13 on the 2nd line one point to the left, allowing white a comfortable connection at 15, but if white can't capture the cutting stone with the ladder below (which he can't with the squared stone present) then black can play up onto the 3rd line giving white a hard time. White could fight with 18 one below but it's a good fight for black. Note white can't push through with 16 at 17 or he gets captured with a tombstone squeeze.

Click Here To Show Diagram Code: [go]$$Bm11 Dia. 9: Redmond's taisha ladder, part 2 $$ +---------------------------------------+ $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . # . . . . . | $$ | . . . O . . . . . , . . . . . X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . O . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , O . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . 6 5 8 . . . . . . . . . . . . . . | $$ | . . 3 4 . . . . . . . . . . . . . . . | $$ | . . 7 O . . . . . . . . . . . . . . . | $$ | . . X O X 1 . . . . . . . . . . . . . | $$ | . . X X O X . . . , . . . . . , X . . | $$ | . . X O O O . 2 . . . . . X . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ +---------------------------------------+[/go]

So white would likely have to concede with something like below, but that's also good for black who has a very thick shape on the left so pleasant centre fighting ahead.

Click Here To Show Diagram Code: [go]$$Bm11 Dia. 10: Redmond's taisha ladder, part 3, white concedes $$ +---------------------------------------+ $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . X . . . . . | $$ | . . . O . . . . . , . . . . . X . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . O . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , O . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . 3 . . . . . . . . . . . . . . . . | $$ | . . 5 O 4 6 . . . . . . . . . . . . . | $$ | . . X O X 1 . 7 . . . . . . . . . . . | $$ | . . X X O X . . . , . . . . . , X . . | $$ | . . X O O O . 2 . . . . . X . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ +---------------------------------------+[/go]

So that's Redmond's hypothesis for why Master doesn't taisha with the top right exchange not present (so the assumption seems to be the taisha wall is a better wall than the knight's press so you prefer it if you can get it without being scared of white fighting back and cutting). It seems plausible to me, but I have a slight feeling it is overly tactical, and I think Master's strength lies more in global judgement so looked for explanations in that vein.

Here is one such hypothesis. In both games without the exchange and the knight's press, Master approached the top left rather than counter pincer. This gives white a choice to pincer and black will probably take the corner. In his review of Li's game, after seeing Li's poor result on the side following the kick, Redmond thought that might have been be better. That would result in the following, note black ends up with a low stone on the top side at 10. I think that given this, if white approached at a now, black would't like to answer low at b, but maybe high, or invade, or kick, or something else. However, maybe my distaste for 2 low stones is too strong as I do see pros doing things like this quite often, but maybe they are playing bad moves at Master level. But if black does the top left approach and take corner with the approach-answer exchange already played he gets into this bad position. So if the top right exchange is made black doesn't want to take the corner after being pincered because it ends up double low, and if there's no other good response to being pincered (for simplicity's sake I only assume taking corner directly, high counter pincer could be a counter-strategy but probably white can fight back strongly given the 2 stones on the left) then you don't want to approach but counter pincer, and if you want to counter pincer you want a stronger/longer wall at lower left so prefer to play the taisha press. QED!

Click Here To Show Diagram Code: [go]$$W Dia. 11: Pincer instead of kick following knight's press $$ +---------------------------------------+ $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . 8 2 4 . 0 . . . . . . . b . . . . . | $$ | . 6 3 O 5 . . . . , . . . . . X . . . | $$ | . 7 9 . . . . . . . . . . . . . . . . | $$ | . . X . . . . . . . . . . . . . a . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . 1 . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , O . . | $$ | . . O . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . X . . . . . . . . . . . . . . . . | $$ | . . . , X X . . . , . . . . . , X . . | $$ | . . . O O . O . . . . . . X . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ +---------------------------------------+[/go]

Another idea I had is that in the taisha variation when Master extends on the top side to reduce the wall, the top right exchange is working well to support that extension. Without it such a play could come under attack:

Click Here To Show Diagram Code: [go]$$B Dia. 12: 1 weaker without support at 2 $$ +---------------------------------------+ $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . 2 . . . . . | $$ | . X . O O X . . 1 . 4 . . . . X . . . | $$ | . . X . . . . . . . . . . . . . . . . | $$ | . . X O O . . . . . . . . . . . 3 . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . X . O . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , O . . | $$ | . . O . O . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . X . X . . . . . . . . . . . . . . | $$ | . . . , O X X X X , . . . . . , X . . | $$ | . . . O . O O O O . . . . X . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ +---------------------------------------+[/go]

So with that introduction out of the way, onto Peng's move!

Click Here To Show Diagram Code: [go]$$B Dia. 13: $$ +---------------------------------------+ $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . 6 . . . . . . . . . . . . . | $$ | . . . 2 . . . . . , . . . . . 1 . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , 3 . . | $$ | . . . 4 . . . . . . . . . 5 . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ +---------------------------------------+[/go]

WIP

John Fairbairn · Post by **John Fairbairn** » Fri May 12, 2017 5:35 am

Re the Black low large shimari position, it is true that White playing on the right side is overwhelmingly popular among pros, but there has been a significant cluster of Master's shimari played by pros from about 2010. I infer that quite a few pros already suspected there was something amiss with the right-side plays.

Regarding the high large shimari by Black (and the particular fuseki shown here), this has occurred quite a lot since 1995, but interestingly is almost exclusively a Japanese thing. From the players involved, often participants in Go Seigen's seminars, I'm strongly inclined to sense the hand of Go yet again.

Uberdude · Post by **Uberdude** » Fri May 12, 2017 5:50 am

John Fairbairn wrote:Re the Black low large shimari position, it is true that White playing on the right side is overwhelmingly popular among pros, but there has been a significant cluster of Master's shimari played by pros from about 2010. I infer that quite a few pros already suspected there was something amiss with the right-side plays.

Interesting; I'm at work so only checked the smaller database at ps.waltheri.net rather than GoGoD, and it only has the high shimari in 2017. I'll take a look at those games at home.

dhu163 · Post by **dhu163** » Sat May 13, 2017 4:01 am

uberdude: 3 posts above, you've made some excellent points, and I strongly agree with all of them. I agree that diagram 10 is good for B. Diagram 11 you make a very interesting QED point that I hadn't noticed at all. I'm unsure as to how master would react to W continuing by approaching the top right though (perhaps it would still respond normally?)

There is one thing in Redmond's Li qincheng video I disagree with - after the shoulder hit on the left, I agree W should crawl first, but I think his suggestion of B double hane in the centre is dubious (I think B should extend and only then hane if W pushes). He then says this is probably W's best variation.

Bill Spight · Post by **Bill Spight** » Mon May 29, 2017 4:16 pm

In which I eat my words.

Click Here To Show Diagram Code: [go]$$Wcm28 AlphaGo self play, game 31 $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . 5 . . . . . . . O . O O . . | $$ | . . . O . . . . . , . . . O X X X . . | $$ | . . . . . . . . . . O O O X X . . . . | $$ | . . . . . . . . . . 1 X X O . . . . . | $$ | . . . . . . . . . . . . . X . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . X . . | $$ | . . . . a . . . . . . . . . . . . . . | $$ | . . 2 . . . . . . . . . . . . . . . . | $$ | . X O 3 . . . . . . . . . . . . . . . | $$ | . . X O . . . . . . . . . . . . . . . | $$ | . . X O . . . 6 . , . . . . . . . . . | $$ | . . X O . . . . . . . . . . . X . . . | $$ | . . 4 . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

Had I seen this sequence in a kyu vs kyu game, I would have praised White for the turn,

, but then have criticized

for allowing, nay, inviting

. There are people who would say that

kills the influence of the White wall. I don't go quite so far, but almost. This is the kind of wall, I would say, that cries out for eye shape. An extension on the bottom side, while not quite making territory because of

, at least provides support to the wall while reducing Black's potential on the bottom half of the board. If you don't like the extension because it does not make territory, at least play the keima at "a".

Click Here To Show Diagram Code: [go]$$Bcm41 See? $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . O . . . . . . . O . O O . . | $$ | . . . O . . . . . , . . . O X X X . . | $$ | . . . . . . . . . . O O O X X . . . . | $$ | . . . . . . . . . . O X X O . . . . . | $$ | . . . . . . . . . . . . . X . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . , . . . . . , . . . . . , . . . | $$ | . . . . . . . . . . . . . . . . X . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . X . . . 1 . . . . . . . . . . . . | $$ | . X O O . . . . . . . . . . . O . . . | $$ | . . X O . . . . . . . . . . . . . . . | $$ | . . X O . . . X . , . . . . X O O . . | $$ | . . X O . . . . . . . . . . X X X O . | $$ | . . X . . . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ ---------------------------------------[/go]

After

I would have said, "See? What could have been an asset has become a liability."

OC, White won a close game.

Life In 19x19

Learning from the Master

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Re: Learning from the Master

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Re: Learning from the Master

Re: Learning from the Master

Re: Learning from the Master

Re: Learning from the Master

Re: Learning from the Master

Re: Learning from the Master

Re: Learning from the Master