It is currently Thu Aug 16, 2018 8:59 am

All times are UTC - 8 hours [ DST ]




Post new topic Reply to topic  [ 8 posts ] 
Author Message
Offline
 Post subject: Opening for black?
Post #1 Posted: Sun May 13, 2018 8:34 am 
Lives in gote

Posts: 338
Liked others: 37
Was liked: 34
Rank: OGS 10 kyu
I was brushing up on my joseki a bit and I was wondering if this could be a decent opening strategy for black?
If white approaches the 3-4 stone, black can almost always make it work so that he gains some strength/influence over the left side, where he already has that D10 stone. So that makes is less interesting for white to approach the 3-4, maybe?

Just a thought I had, let me know what you think. Since this is no common opening, there's probably something wrong with it, so I'm interested to know what it is I'm missing :) It's close to sanren-sei, so maybe the sanren-sei does the same just a bit better?

And also: Would the opening be better/worse with other white stones, instead of niren-sei?

Also let's call this the Impolite Opening since black obviously didn't open at the upper right corner!


Click Here To Show Diagram Code
[go]$$c Opening for black?
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X , . . . . . , . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

Top
 Profile  
 
Offline
 Post subject: Re: Opening for black?
Post #2 Posted: Sun May 13, 2018 9:11 am 
Lives in gote

Posts: 346
Liked others: 138
Was liked: 158
The only way to know is to play. Chances are your opponent will play here. What are your thoughts?

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


You should also minimally prepare against this:

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


And because it's 2018 :)

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


This post by Calvin Clark was liked by: Akura
Top
 Profile  
 
Offline
 Post subject: Re: Opening for black?
Post #3 Posted: Sun May 13, 2018 9:26 am 
Judan

Posts: 7978
Liked others: 1408
Was liked: 1259
KGS: Kirby
Tygem: 커비라고해
I think it's inconsistent. The two star point stones aim for influence that has potential to make a nice shape on the top and bottom sides.

But the territorial 3-4 stone invites white to approach and spoil that influence.

I'd only recommend this opening if you had a special plan for white's approach.

If you're not going for San-ren-sei, the 3-4 stone should emphasize influence. You could even play around like this:

Click Here To Show Diagram Code
[go]$$c Opening for black?
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , B . . . . , . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

_________________
Focus on improving yourself rather than trying to improve others.


This post by Kirby was liked by: Calvin Clark
Top
 Profile  
 
Offline
 Post subject: Re: Opening for black?
Post #4 Posted: Sun May 13, 2018 10:13 am 
Judan

Posts: 7419
Liked others: 1931
Was liked: 2663
Ian Butler wrote:
I was brushing up on my joseki a bit and I was wondering if this could be a decent opening strategy for black?


This:
Click Here To Show Diagram Code
[go]$$c Opening for black?
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X , . . . . . , . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


Why not?
Quote:
If white approaches the 3-4 stone, black can almost always make it work so that he gains some strength/influence over the left side, where he already has that D10 stone. So that makes is less interesting for white to approach the 3-4, maybe?


No. One general rule in the opening is that box shapes are good. So if you have two stones forming one side of a box, you usually want to extend from them to form a triangle, which threatens to add another stone to form a box. In this position Black is threatening to form triangles on both the top and bottom sides, as well as a smaller triangle by enclosing the top left corner. So White will want to approach both left corners to prevent that, although he probably cannot prevent both triangles, by miai.

Another general rule is that the wider open space on the side makes plays there bigger. So White will usually prefer to approach the top left corner than the bottom left corner. BTW, you can see that rule in action in the corresponding position before :b5: at https://alphagoteach.deepmind.com . AlphaGo prefers to enclose the top left corner (top right in that case) or approach White's top corner than to approach White's bottom corner.

That said, I found 8 roughly similar position on Waltheri ( http://ps.waltheri.net ), with 4-4 results. So even if this opening is inferior, it is only a little inferior. :)

Click Here To Show Diagram Code
[go]$$Bc 2 space high approach
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . a . . . . . . . . . . . . . |
$$ | . . X , . 6 . . . , . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


White has a nice play at :w6:, or possibly the large knight's approach at "a".

Click Here To Show Diagram Code
[go]$$Bc Pincer
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X , 6 . . 7 . , . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 9 . 8 . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . B . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


:w6: invites the two space high pincer. The value of :bc: lies not so much in making territory as in attacking the White stones.

_________________
The Adkins Principle:

At some point, doesn't thinking have to go on?

— Winona Adkins

Top
 Profile  
 
Offline
 Post subject: Re: Opening for black?
Post #5 Posted: Sun May 13, 2018 11:07 am 
Lives in gote
User avatar

Posts: 668
Location: Earth
Liked others: 203
Was liked: 108
ELF thinks not:


Attachments:
fusekianswerelf.jpg
fusekianswerelf.jpg [ 171.05 KiB | Viewed 359 times ]


Last edited by Gomoto on Sun May 13, 2018 12:19 pm, edited 1 time in total.
Top
 Profile  
 
Offline
 Post subject: Re: Opening for black?
Post #6 Posted: Sun May 13, 2018 11:43 am 
Lives with ko

Posts: 238
Liked others: 0
Was liked: 53
Rank: KGS 2k
GD Posts: 100
KGS: Tryss
Doesn't ELF consider that Black has 47% winrate on an emptyboard?

For exemple, LeelaZero evaluate the sanrensei about the same as this opening (and its evaluation of this position is the same as in your screenshot).

So, it should be perfectly playable for humans

Top
 Profile  
 
Offline
 Post subject: Re: Opening for black?
Post #7 Posted: Sun May 13, 2018 12:11 pm 
Lives in gote
User avatar

Posts: 668
Location: Earth
Liked others: 203
Was liked: 108
ELF starts with 49.5% for black, 56.5% for white doesn't cut it for me.


Last edited by Gomoto on Sun May 13, 2018 12:20 pm, edited 1 time in total.
Top
 Profile  
 
Offline
 Post subject: Re: Opening for black?
Post #8 Posted: Sun May 13, 2018 12:13 pm 
Lives in gote
User avatar

Posts: 668
Location: Earth
Liked others: 203
Was liked: 108
ELF starts with 49.5% for black, 56.5% for white doesn't cut it for me.

(also have a look here: https://lifein19x19.com/forum/viewtopic.php?p=231137#p231137)


... and be assured you can feel the 7% difference in winning chance as human quite well over the board.

(@Tryss, thanks for your post, wrong Leela pic updated to Elf pic.)

Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 8 posts ] 

All times are UTC - 8 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 2 guests


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