It is currently Thu Oct 31, 2024 3:57 pm

All times are UTC - 8 hours [ DST ]




Post new topic Reply to topic  [ 7 posts ] 
Author Message
Offline
 Post subject: Opening problems for AI: Problem 7
Post #1 Posted: Wed Jun 17, 2020 11:50 am 
Honinbo

Posts: 10905
Liked others: 3651
Was liked: 3374
Here is another surprisingly early move by Takagawa that Elf really, really does not like. It comes from GoGoD 1952-01-09a, vs. Kitani. Takagawa was on his way to his first Honinbo title.

Click Here To Show Diagram Code
[go]$$Bc Black to play
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . O . . . . . . . . . . . . . |
$$ | . . O , . . . . . , . . . . . X . . . |
$$ | . . X X . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O , X . . . . , . . . . . X . . . |
$$ | . . . . O X . . . . . . . . . . . . . |
$$ | . . . . O . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

The bottom left corner is pretty much a dead giveaway that Kitani was playing White. It is one of his trademark joseki.

There are many possibilities, so different AI may well have different preferences. But I doubt if any of them likes Takagawa's play.

_________________
The Adkins Principle:
At some point, doesn't thinking have to go on?
— Winona Adkins

Visualize whirled peas.

Everything with love. Stay safe.


Last edited by Bill Spight on Wed Jun 17, 2020 12:44 pm, edited 1 time in total.
Top
 Profile  
 
Offline
 Post subject: Re: Opening problems for AI: Problem 7
Post #2 Posted: Wed Jun 17, 2020 12:14 pm 
Honinbo

Posts: 10905
Liked others: 3651
Was liked: 3374
Click Here To Show Diagram Code
[go]$$Bcm13 Standard extension
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . O . . . . . . . . . . . . . |
$$ | . . O , . . . . . , . . . . . X . . . |
$$ | . . X X . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 1 . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O , X . . . . , . . . . . X . . . |
$$ | . . . . O X . . . . . . . . . . . . . |
$$ | . . . . O . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

:b13: is a standard, textbook play, but Elf reckons that it loses 21½% to a play against the bottom left corner.


Click Here To Show Diagram Code
[go]$$Bcm13 Bottom side moyo
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . O . . . . . . . . . . . . . |
$$ | . . O , . . . . . , . . . . . X . . . |
$$ | . . X X . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 4 . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . 3 . . . . . . . . . . . . . . |
$$ | . . O 2 X . . . . , . . . . . X . . . |
$$ | . . . . O X . . . . . . 5 . . . . . . |
$$ | . . . . O 1 . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

In Elf's mainline variation, :b13: blocks White's group from the bottom side, and after White solidifies the corner, :b17: stakes out the bottom side. It's an early moyo, but Elf still likes it. ;) I think that this line illustrates that the Black extension on the left side is just not big enough, by comparison.

Click Here To Show Diagram Code
[go]$$Wcm14 Elf's reply
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . O . . . . . . . . . . 5 . . |
$$ | . . O , . . . . . , . . . . . X . . . |
$$ | . . X X . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . O 2 X 1 . . . , . . . . . X . . . |
$$ | . . 3 . O X . . . . . . . 4 . . . . . |
$$ | . . . . O . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

In the actual game, Kitani played :w14: at 15, but Elf prefers the cut by 13%. :b17: still encloses the bottom right corner, but without forming a framework.

_________________
The Adkins Principle:
At some point, doesn't thinking have to go on?
— Winona Adkins

Visualize whirled peas.

Everything with love. Stay safe.

Top
 Profile  
 
Offline
 Post subject: Re: Opening problems for AI: Problem 7
Post #3 Posted: Wed Jun 17, 2020 1:55 pm 
Judan

Posts: 6230
Liked others: 0
Was liked: 793
"standard, textbook play" says nothing about whether it is a locally or globally considered play. The extension is mainly locally motivated.

My applicable global textbook-like advice is: defend the weakest important group first. The lower black group was weaker than the left black group.

Top
 Profile  
 
Offline
 Post subject: Re: Opening problems for AI: Problem 7
Post #4 Posted: Thu Jun 18, 2020 2:08 am 
Judan

Posts: 6725
Location: Cambridge, UK
Liked others: 436
Was liked: 3719
Rank: UK 4 dan
KGS: Uberdude 4d
OGS: Uberdude 7d
A year ago Jean-Sébastien Lechasseur found a very normal opening position in which LeelaZero with 2 million playouts preferred Kitani's exotic joseki:

https://www.facebook.com/groups/go.igo. ... 599366514/

Pics copied for those who avoid facebook:

Attachment:
lzkitani.jpg
lzkitani.jpg [ 92.74 KiB | Viewed 6268 times ]


mainline:
Attachment:
lzkitani2.jpg
lzkitani2.jpg [ 83.41 KiB | Viewed 6268 times ]


This post by Uberdude was liked by: Bill Spight
Top
 Profile  
 
Offline
 Post subject: Re: Opening problems for AI: Problem 7
Post #5 Posted: Thu Jun 18, 2020 3:47 am 
Honinbo

Posts: 10905
Liked others: 3651
Was liked: 3374
Thanks, Uberdude. :)

Interesting that White's reply to the Black sagari is to block on the 2d line. The main replies are the stand on the 5-5 or the hanging connection on the 5-6, but Kitani also shows the block in his book, Watashi no Go, vol. 2. :)

_________________
The Adkins Principle:
At some point, doesn't thinking have to go on?
— Winona Adkins

Visualize whirled peas.

Everything with love. Stay safe.

Top
 Profile  
 
Offline
 Post subject: Re: Opening problems for AI: Problem 7
Post #6 Posted: Fri Jun 19, 2020 8:56 am 
Lives in sente
User avatar

Posts: 918
Liked others: 395
Was liked: 163
Rank: German 2 dan
“Watashi no Go” is quite a title… ^^

_________________
A good system naturally covers all corner cases without further effort.

Top
 Profile  
 
Offline
 Post subject: Re: Opening problems for AI: Problem 7
Post #7 Posted: Fri Jun 04, 2021 9:56 am 
Lives in gote

Posts: 470
Liked others: 62
Was liked: 278
Rank: UK 2d Dec15
KGS: mathmo 4d
IGS: mathmo 4d
Speculatively:
Current position:
1. Locally, F2, F4, E5 come to mind. F2 seems to be most common to properly punish W's poor shape, but I worry about making it work with the left. How about F2 D4 E5 D6 C11 J4
2. On the left, D10 or C10 seem natural. D10 F4 O3

Opp to play
1. In lower left, W cut is a move but not very efficient when already on 2nd line. My instinct is C11/D12 ish

Past:
1. Lower left means B probably slightly ahead

Check:
1. close in some places

Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 7 posts ] 

All times are UTC - 8 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group