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 Post subject: Opening problems for AI: Problem 45
Post #1 Posted: Sun Aug 16, 2020 12:11 pm 
Honinbo

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It is late in the opening.

Black to play.

As always, assume komi.

Click Here To Show Diagram Code
[go]$$Bcm43 Black to play
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . a . . . . . . . |
$$ | . . . . . . . . . X . . . . . X . . . |
$$ | . . . , . . . . . X O . . . . , . . . |
$$ | . . . . . . . . . b O . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . , . . . . . , . . . . . O X O . |
$$ | . . . . . . . . . . . . . . . X X O . |
$$ | . . . . . . . . . . . . . . X X O O . |
$$ | . . O . . . . . . . . X . X O O X . . |
$$ | . . . X . . . . . . . . . X . . . . . |
$$ | . . O . . . . . O . . O . O O O . . . |
$$ | . . . , X . . X O , . . . X . , O . . |
$$ | . . . X . . . X O . O . . . X O . . . |
$$ | . . . . . . . . . . . . . . . c . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

Which do you choose among a, b, or c? One is the human's play, one is Elf's top choice, and one is Elf's second choice, with basically the same winrate as its top choice. The human play is very likely a blunder, losing 23½% to Elf's top choice.

Enjoy!

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 Post subject: Re: Opening problems for AI: Problem 45
Post #2 Posted: Sun Aug 16, 2020 3:01 pm 
Gosei
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Just stopping by to say that I like this series, even though I get most answers wrong.

I am surprised none of the proposed answers consists in playing in the empty corner.

I don't understand answer "c", I don't see how Black can make life.

I like "b", which puts pressure on the two white stones and pushes them towards Black's thickness.
Playing at "a" would allow White "b" and make White's life too easy.

So I vote for "b". After that, not sure if Black should continue pushing, or play knight's move, or play elsewhere.


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 Post subject: Re: Opening problems for AI: Problem 45
Post #3 Posted: Sun Aug 16, 2020 6:28 pm 
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jlt wrote:
Just stopping by to say that I like this series, even though I get most answers wrong.

I am surprised none of the proposed answers consists in playing in the empty corner.


The top left became the last empty corner at move 6, and Elf preferred to occupy it then. Since then Elf has preferred to play there nearly half the time. I was a bit surprised that Elf did not prefer it for this move, as well. AFAIK, KataGo and other top bots prefer it now, too. Still, I am reasonably certain that they will greatly prefer Elf's top choice to the human move. :)


And thanks for the vote of confidence. :) Truth to say, I was about ready to end it some weeks ago for lack of interest. :-|

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 Post subject: Re: Opening problems for AI: Problem 45
Post #4 Posted: Sun Aug 16, 2020 7:11 pm 
Gosei

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One answer consists of playing in the upper left (b). It is just a matter of how to occupy the upper left in an optimal way.

I do not think moves like c are actually good moves although bots bring them up all the time. They don't hurt, but they are better left for later. Room to grow for neural networks.


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 Post subject: Re: Opening problems for AI: Problem 45
Post #5 Posted: Mon Aug 17, 2020 1:01 pm 
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Bill Spight wrote:
Click Here To Show Diagram Code
[go]$$Bcm43 Black to play
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . a . . . . . . . |
$$ | . . . . . . . . . X . . . . . X . . . |
$$ | . . . , . . . . . X O . . . . , . . . |
$$ | . . . . . . . . . b O . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . , . . . . . , . . . . . O X O . |
$$ | . . . . . . . . . . . . . . . X X O . |
$$ | . . . . . . . . . . . . . . X X O O . |
$$ | . . O . . . . . . . . X . X O O X . . |
$$ | . . . X . . . . . . . . . X . . . . . |
$$ | . . O . . . . . O . . O . O O O . . . |
$$ | . . . , X . . X O , . . . X . , O . . |
$$ | . . . X . . . X O . O . . . X O . . . |
$$ | . . . . . . . . . . . . . . . c . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


I think this has to be 'b'. To play 'a' just crawls low in an area of Black strength.

Far more interesting, though, is the reason for wanting to play 'c'. I don't see anything concrete, but there are so many tantalizing threads. A few thoughts:

Click Here To Show Diagram Code
[go]$$Bcm43 Black to play
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . X . . . . . X . . . |
$$ | . . . , . . . . . X O . . . . , . . . |
$$ | . . . . . . . . . . O . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . , . . . . . , . . . . . O X O . |
$$ | . . . . . . . . . . . . . . . X X O . |
$$ | . . . . . . . . . . . . . . X X O O . |
$$ | . . O . . . . . . . . X . X O O X . . |
$$ | . . . X . . . . . . . . . X . . d . . |
$$ | . . O . . . . . O . . O b O O O . . . |
$$ | . . . , X . . X O , . . . X . , O . . |
$$ | . . . X . . . X O . O . . . X O . c . |
$$ | . . . . . . . . . . . . . a . 1 2 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]



Assuming white responds in the obvious way, black has 'a' that creates eye shape. There's an interesting cut at 'b' that may be useful in combination with 'a'. Maybe white will have to pull those black stones off the board. Black 'c' may also be interesting, and may combine with 'd' in certain situations to allow black to threaten the four white stones on the side.

So many almosts and maybes, but nothing concrete. It's either an awe-inspiring move of profound subtlety, or it's a computer trying to delay figuring out what to do. The latter is actually quite comforting...I find myself doing the same far too often. :)


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 Post subject: Re: Opening problems for AI: Problem 45
Post #6 Posted: Tue Aug 18, 2020 6:26 am 
Oza
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The fundamental choice is between A or B, while C looks incidental to the game, a probe which only professionals or even AI can come up with. B is the more severe move, influencing the open corner and looks like an obvious preference over the more leisurely A.


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 Post subject: Re: Opening problems for AI: Problem 45
Post #7 Posted: Tue Aug 18, 2020 2:39 pm 
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The game is GoGoD 1806-01-06a, a Castle Game between Yasui Senchi Senkaku (W) and Hayashi Monetsu.

Click Here To Show Diagram Code
[go]$$Bcm43 Game record
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . 1 . . . . . . . |
$$ | . . . . . . . . . X . . . . . X . . . |
$$ | . . a , . . . . . X O . . . . , . . . |
$$ | . . . . . . . . . 2 O . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . , . . . . . , . . . . . O X O . |
$$ | . . . . . . . . . . . . . . . X X O . |
$$ | . . . . . . . . . . . . . . X X O O . |
$$ | . . O . . . . . . . . X . X O O X . . |
$$ | . . . X . . . . . . . . . X . . . . . |
$$ | . . O . . . . . O . . O . O O O . . . |
$$ | . . . , X . . X O , . . . X . , O . . |
$$ | . . . X . . . X O . O . . . X O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

:b43: was a likely blunder, even with no komi. With komi, Elf reckons that it lost 23½% to the push at 44. It also reckons that :w44: was a minor error, losing 7½% to occupying the last open corner at a.

The top left corner became the last open corner at move 5. Since then, Elf has preferred to occupy it almost half the time. It is surprising that the human players did not occupy it by now, as this was the 19th century, and the primacy of the corners had been established.

Next is Elf's mainline variation for :w44:

Click Here To Show Diagram Code
[go]$$Wcm44 Mainline variation for :w44:
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . X . . . . . . . |
$$ | . . . . . . . . . X . . . . . X . . . |
$$ | . . 1 , . . . . . X O . . . . , . . . |
$$ | . . . . . . . . 4 3 O . . . . . X . . |
$$ | . . . . . . . . 5 6 . . . . . . . . . |
$$ | . . . . . . . . . a 2 . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . , . . . . . , . . . . . O X O . |
$$ | . . . . . . . . . . . . . . . X X O . |
$$ | . . . . . . . . . . . . . . X X O O . |
$$ | . . O . . . . . . . . X . X O O X . . |
$$ | . . . X . . . . . . . . . X . . . . . |
$$ | . . O . . . . . O . . O . O O O . . . |
$$ | . . . , X . . X O , . . . X . , O . . |
$$ | . . . X . . . X O . O . . . X O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

:b45: attacks with a boshi, but a was also playable.
:w46: and :w48: create some aji.

Click Here To Show Diagram Code
[go]$$Wcm50 Mainline variation for :w44:, continued
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . X . . . . . . . |
$$ | . . . . . . . . . X . . . . . X . . . |
$$ | . . O , . . . . . X O . . . . , . . . |
$$ | . . . . . . . . X O O . . . . 4 X . . |
$$ | . . . . . . . . O X . . . . . 1 3 . . |
$$ | . . . . . . . . . . X . 2 . . . . . . |
$$ | . . . . . . . . . . . . . . . . 6 . . |
$$ | . . . . . . . . . . . . . . . . X 5 . |
$$ | . . . , . . . . . , . . . . . O X O . |
$$ | . . . . . . . . . . . . . . . X X O . |
$$ | . . . . . . . . . . . . . . X X O O . |
$$ | . . O . . . . . . . . X . X O O X . . |
$$ | . . . X . . . . . . . . . X . . . . . |
$$ | . . O . . . . . O . . O . O O O . . . |
$$ | . . . , X . . X O , . . . X . , O . . |
$$ | . . . X . . . X O . O . . . X O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

:w50: plays a shoulder hit against the corner. Then :b51: continues a large scale center oriented attack. :w52: pushes down and :b53: blocks from the corner. Then :w54: crawls on the 2d line, threatening to connect to the White corner stones. (Because Elf does not show its plays that get fewer than 1500 rollouts, we cannot be sure of its next choice for White.)

Elf's second choice

Click Here To Show Diagram Code
[go]$$Bcm43 Second choice
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . X . . . . . X . . . |
$$ | . . 5 , . . . . . X O . . . . , . . . |
$$ | . . . . . . . . . 3 O . . . . . X . . |
$$ | . . . . . . . . . . 4 . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . , . . . . . , . . . . . O X O . |
$$ | . . . . . . . . . . . . . . . X X O . |
$$ | . . . . . . . . . . . . . . X X O O . |
$$ | . . O . . . . . . . . X . X O O X . . |
$$ | . . . X . . . . . . . . . X . . . . . |
$$ | . . O . . . . . O . . O . O O O . . . |
$$ | . . . , X . . X O , . . . X . , O . . |
$$ | . . . X . . . X O . O . . . X O . . . |
$$ | . . . . . . . . . . . . . . . 1 2 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

:b43: plays sente in the corner, and then comes back to the top side to push towards the center, and then occupies the last open corner. In the actual game the exchange in the bottom right corner occurred at move 115 as a ko threat and reply.

Top choice: Build a wall, then occupy the corner

Click Here To Show Diagram Code
[go]$$Bcm43 Push towards the center
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . X . . . . . X . . . |
$$ | . . 3 , . . . . . X O . . . . , . . . |
$$ | . . . . . . . . . 1 O . . . . . X . . |
$$ | . . . . . . 9 7 5 4 2 . . . . . . . . |
$$ | . . . . . . . 8 6 . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . , . . . . . , . . . . . O X O . |
$$ | . . . . . . . . . . . . . . . X X O . |
$$ | . . . . . . . . . . . . . . X X O O . |
$$ | . . O . . . . . . . . X . X O O X . . |
$$ | . . . X . . . . . . . . . X . . . . . |
$$ | . . O . . . . . O . . O . O O O . . . |
$$ | . . . , X . . X O , . . . X . , O . . |
$$ | . . . X . . . X O . O . . . X O . . . |
$$ | . . . . . . . . . . . . . . . a . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

:b43: pushes towards the center with sente, then :b45: occupies the last open corner. (Finally! ;)) :b45: could also take the sente at a first. :w46: plays the turn in the center and then White strengthens the center while Black strengthens the top side.


Click Here To Show Diagram Code
[go]$$Wcm52 Mainline, continued
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . 2 . . . . . X . . . . . X . . . |
$$ | . . X 1 5 . . . . X O . . . . , . . . |
$$ | . 7 3 4 . . . . . X O . . . . . X . . |
$$ | . . 6 . . . X X X O O . . . . . . . . |
$$ | . . . . . . . O O . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . , . . . . . , . . . . . O X O . |
$$ | . . . . . . . . . . . . . . . X X O . |
$$ | . . . . . . . . . . . . . . X X O O . |
$$ | . . O . . . . . . . . X . X O O X . . |
$$ | . . . X . . . . . . . . . X . . . . . |
$$ | . . O . . . . . O . . O . O O O . . . |
$$ | . . . , X . . X O , . . . X . , O . . |
$$ | . . . X . . . X O . O . . . X O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

:w52: plays the attachment to the 3-4 stone in the corner, and the fighting starts. Again, Elf doe not show the rest.

Now let's look at variations for White for :w52: and :w50:.

Click Here To Show Diagram Code
[go]$$Wcm52 Variation for :w52:
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . X 1 . . . . X . . . |
$$ | . . X . . . . . . X O . . . . , . . . |
$$ | . . . 2 . . . . . X O . . . . . X . . |
$$ | . . . . . . X X X O O . . . . . . . . |
$$ | . . . . . . . O O . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . 3 , . . . . . , . . . . . O X O . |
$$ | . . . . . . . . . . . . . . . X X O . |
$$ | . . . . . . . . . . . . . . X X O O . |
$$ | . . O . . . . . . . . X . X O O X . . |
$$ | . . . X . . . . . . . . . X . . . . . |
$$ | . . O . . . . . O . . O . O O O . . . |
$$ | . . . , X . . X O , . . . X . , O . . |
$$ | . . . X . . . X O . O . . . X O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

:w52: is also a good play, pushing down in the middle of top side. :b53: encloses the top left, and then :w54: makes a base on the left side.

Click Here To Show Diagram Code
[go]$$Wcm50 Variation for :w50:
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 6 2 . . . . . X . . . . . X . . . |
$$ | . . X 1 5 . . . . X O . . . . , . . . |
$$ | . . 3 4 . . . . . X O . . . . . X . . |
$$ | . . . . . . a X X O O . . . . . . . . |
$$ | . . . . . . . . O . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . , . . . . . , . . . . . O X O . |
$$ | . . . . . . . . . . . . . . . X X O . |
$$ | . . . . . . . . . . . . . . X X O O . |
$$ | . . O . . . . . . . . X . X O O X . . |
$$ | . . . X . . . . . . . . . X . . . . . |
$$ | . . O . . . . . O . . O . O O O . . . |
$$ | . . . , X . . X O , . . . X . , O . . |
$$ | . . . X . . . X O . O . . . X O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

:w50: attaches to the corner stone and the fight develops. In this case, however, without the strength of a Black stone at a, :b55: solidly connects on the 3-3.

Click Here To Show Diagram Code
[go]$$Wcm56 Variation for :w50:, continued
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X X . . . . . X . . . . . X . . . |
$$ | . . X O O . . . . X O . . . . , . . . |
$$ | . . O X 3 . . . . X O . . . . . X . . |
$$ | . . . 4 5 . 2 X X O O . . . . . . . . |
$$ | . . . 6 7 . 9 1 O . . . . . . . . . . |
$$ | . . . 8 . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . , . . . . . , . . . . . O X O . |
$$ | . . . . . . . . . . . . . . . X X O . |
$$ | . . . . . . . . . . . . . . X X O O . |
$$ | . . O . . . . . . . . X . X O O X . . |
$$ | . . . X . . . . . . . . . X . . . . . |
$$ | . . O . . . . . O . . O . O O O . . . |
$$ | . . . , X . . X O , . . . X . , O . . |
$$ | . . . X . . . X O . O . . . X O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

Having gotten that concession, :w56: pushes again in the center and then :w58: - :w64: push out of the corner into the center in exchange for Black territory on the top left side. :w58: could also be at 59, for a driving tesuji.


To me, :b43: in the game, while a kind of joseki, also reflects a blindness to the value of the top left corner, which has afflicted both players for much of the game. Black, for instance, could have occupied the last corner instead of extending on the top side, and White could have done the same instead of playing the shoulder hit which led to the current situation. Pushing up with :b43: to build a wall and then occupy the corner seems like an ideal development for Black at this point in the game.

As for the sente in the bottom right, the bots seem to like to make such sente moves inside the opponent's territorial framework, as well as other kikashi, before returning to the main field of battle. Sakata used to play kikashi early, but the only pro I know of who used to make plays like the hane in the bottom right was Kitani Minoru. It is a style of play I do not understand, and so do not really have much to say about it. :-|

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 Post subject: Re: Opening problems for AI: Problem 45
Post #8 Posted: Tue Aug 18, 2020 6:30 pm 
Gosei

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C is not a probe, white has not several options to respond

C loses a ko threat

C is a bad move that does no harm immediatly

Humans can recognize C as a bad move

AI has problems to see C is bad


Last edited by Gomoto on Wed Aug 19, 2020 2:40 am, edited 1 time in total.
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Post #9 Posted: Wed Aug 19, 2020 1:40 am 
Oza

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Quote:
C is not a probe, white has not several options to respond


It is a probe. He does not need the opponent to have several options - two is enough: O2 and R2 will do

Quote:
C looses a ko threat


(a) loses - Dutch people, please note. No offence intended, but the non-word 'looses' really sounds like scratching down a window pane to many natives who would assume it rhymes with 'mooses'. American mis-spellings such as center when made by Brits are even more irritating. And more English speakers in the world follow British spelling then US spellings, I believe. At any rate it's more of an even split than you might imagine.

(b) but it also makes future ko threats bigger

Quote:
C is a bad move that does no harm immediatly


Lack of immediate effect sounds plausible but that doesn't make it bad - just wishy-washy

Quote:
Humans can recognize C as a bad move


Humans can also recognise C as not a bad move

Quote:
AI has problems to see C is bad


On behalf of the bots: "Sez you and whose army?"

My own perception is that A is not good. Many people amateurs play this automatically as a shape move, but pros seem to play it only when it is essential, and I see no urgency here.

I favour B for a slightly odd reason. Until last night I would have assumed a move in the upper-left corner was mandatory for a bot. But I saw a vaguely similar situation in a game by the utterly brilliant Huang Longshi where he played a B-like move, treating it as a probe to see which side the opponent would start off in the corner. Because this is not the fuseki, the principle of prior occupancy of an empty corner does not carry the same force as it would there. It can be treated as a miai situation here. And of course the elsewhere move, B, has a lot going for it in addition to its probing function. (That said, I'd still I'd be very surprised if a Black move in the UR corner is a bad move.)


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Post #10 Posted: Wed Aug 19, 2020 2:57 am 
Gosei

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O2 is not an option but a losing move. In this sense C would be a probe into the ability of the opponent or should we say a trick move.

I am fine with calling it wishy-washy over bad.

It will be interesting if further AI development will change the evaluation of this and similar moves.

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Post #11 Posted: Wed Aug 19, 2020 9:38 am 
Judan

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John Fairbairn wrote:
Quote:
C is not a probe, white has not several options to respond


It is a probe. He does not need the opponent to have several options - two is enough: O2 and R2 will do

(b) but it also makes future ko threats bigger


I'd say the most likely 2nd choice that makes this a probe is the tenuki choice (with O2 3rd), which links to the making a bigger ko threat point. This black 1 is a few points bigger as a ko threat than q2 as a ko threat (say 34 points versus 30 points, pulling numbers out of the air), so if there's a ko happening which needs a >30 and <=34 point threat then it's good if you have already made this exchange because it generated a valid threat where you otherwise wouldn't have one, but if it's a ko for which <30 is valid then it's bad to have wasted 1 threat, and if the ko needs >34 then it didn't matter now and depends on the size of future kos. But I don't yet foresee any such 30-34 point kos developing and doubt Elf does either, so it's probably more a horizon effect of making incidental exchanges to get more stones on the board and increase the confidence of the winrate.

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


The probe-do-you-wanna-tenuki is similar to why bots like to make this exchange early: if you do it latter when there's a big fight that you want it to be a sente exchange in there's a danger it's not big enough and gets tenukid.

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


John Fairbairn wrote:
Quote:
AI has problems to see C is bad


On behalf of the bots: "Sez you and whose army?"

I ne-er thought I'd see the day!

John Fairbairn wrote:
American mis-spellings such as center when made by Brits are even more irritating.

C'est moi?!


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Post #12 Posted: Wed Aug 19, 2020 10:48 am 
Honinbo

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John Fairbairn wrote:
American mis-spellings such as center when made by Brits are even more irritating. And more English speakers in the world follow British spelling then US spellings, I believe. At any rate it's more of an even split than you might imagine.


Online Etymology Dictionary wrote:
The spelling with -re was popularized in Britain by Johnson's dictionary (following Bailey's), though -er is older and was used by Shakespeare, Milton, and Pope.

:mrgreen:

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Post #13 Posted: Wed Aug 19, 2020 11:53 am 
Oza
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John Fairbairn wrote:

(a) loses - Dutch people, please note. No offence intended, but the non-word 'looses' really sounds like scratching down a window pane to many natives who would assume it rhymes with 'mooses'. American mis-spellings such as center when made by Brits are even more irritating. And more English speakers in the world follow British spelling then US spellings, I believe. At any rate it's more of an even split than you might imagine.


Is this a test for the Dutch speakers, John?


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Post #14 Posted: Wed Aug 19, 2020 1:58 pm 
Oza

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Quote:
The spelling with -re was popularized in Britain by Johnson's dictionary (following Bailey's), though -er is older and was used by Shakespeare


Well, Shakespeare couldn't even spell his own name consistently. And let us not forget that American spellings were popularised by a Scot.

Quote:
Is this a test for the Dutch speakers, John?


Sorry, but I don't understand the question. I'm just observing that Dutch people seem particularly prone to loose usage of lose. I've seen it picked up on several other non-go forums, so it's not just me being picky.

It's not really that it irritates me. It's more of a fascination. Dutch people are generally so superb at English (and other languages) that to see this blindspot over and over again makes me wonder what is going on. The irritation I feel is that, even as a linguist, I don't understand how it comes about. (The only other constant hiccup I can think of by Dutch people is "an applause". This is one of Andre Rieu's solecisms, who overuse of it makes me cringe, even though he is otherwise one of my favourite entertainers. But at least I can see where it comes from.)

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Post #15 Posted: Wed Aug 19, 2020 2:19 pm 
Honinbo

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John Fairbairn wrote:
Quote:
The spelling with -re was popularized in Britain by Johnson's dictionary (following Bailey's), though -er is older and was used by Shakespeare


Well, Shakespeare couldn't even spell his own name consistently.


Neither could Maleore. ;)

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Post #16 Posted: Wed Aug 19, 2020 2:41 pm 
Oza
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John Fairbairn wrote:
Quote:
The spelling with -re was popularized in Britain by Johnson's dictionary (following Bailey's), though -er is older and was used by Shakespeare


Well, Shakespeare couldn't even spell his own name consistently. And let us not forget that American spellings were popularised by a Scot.

Quote:
Is this a test for the Dutch speakers, John?


Sorry, but I don't understand the question. I'm just observing that Dutch people seem particularly prone to loose usage of lose. I've seen it picked up on several other non-go forums, so it's not just me being picky.

It's not really that it irritates me. It's more of a fascination. Dutch people are generally so superb at English (and other languages) that to see this blindspot over and over again makes me wonder what is going on. The irritation I feel is that, even as a linguist, I don't understand how it comes about. (The only other constant hiccup I can think of by Dutch people is "an applause". This is one of Andre Rieu's solecisms, who overuse of it makes me cringe, even though he is otherwise one of my favourite entertainers. But at least I can see where it comes from.)


I was just mocking your then/than mistake (in bold) :)

I beg to differ about the Dutch excellence at other languages. I've rather been awestruck by the Swedes in that regard, their fellow Scandinavians (a word they all hate) and likewise by Russians, Iranians (?), Syrians and in general people from the Middle East. I'm also making a modest case for us, Belgian Dutch speakers, who have been squeezed between and ruled by so many different cultures that we've become accustomed to acquire them. The Dutch have good command of English and German but we're more into the Roman languages - if I can be so awfully generalizing.

As to "loose/lose" - it continues to baffle me too how such an easy mistake is so stubborn to cure. In our region, which I praised a moment ago, there are other seemingly incurable errors, like the pronunciation of the verb "to interpret" (said: in-ter-PREET) or "to determine" (DEE-ter-mine, where mine is pronounced like the possessive).

And thanks for "an applause": it's something I didn't know to be wrong. Only recently I unlearned the phrase "according to me" after a native speaker had pointed it out as a rather awkward thing to say.

Cheers!

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Post #17 Posted: Wed Aug 19, 2020 2:50 pm 
Honinbo

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Knotwilg wrote:
Only recently I unlearned the phrase "according to me" after a native speaker had pointed it out as a rather awkward thing to say.


Phil Harris wrote:
We ain't just gonna keep on playin' this game accordin' to Mister Hoylee.
We gon' play this game accordin' to me!

;)

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Post #18 Posted: Thu Aug 20, 2020 2:44 pm 
Oza

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Bill

You mentioned Johnson's dictionary. He had a few notable opponents in Scotland, but the most notable was Robert Fergusson, who was a forerunner of Burns in writing Scots poetry. He is most famous for his "Ode to the Gowdspink" (the goldfinch) but he could match Johnson in both "normal" English and sarcasm. It took me a while to dig it out, but I think it was worth the time as you are one of the few here that might appreciate it. Note that it's (ostensibly) English but I see it got at least as many wavy wed lines from the spell checker as did To a Mouse.

There's a sly joke in the last line. You're not supposed to pronounce the final 'd' in Loch Lomond. Presumably Johnson did.

‘To Dr Samuel Johnson: Food for a New Edition of His Dictionary’
Robert Fergusson

Great Pedagogue! whose literarian lore,
With syllable on syllable conjoined,
To transmutate and varify, hast learned
The whole revolving scientific names
That in the alphabetic columns lie,
Far from the knowledge of mortalic shapes;
As we, who never can peroculate
The miracles by thee miraculized,
The Muse, silential long, with mouth apert,
Would give vibration to stagnatic tongue,
And loud encomiate thy puissant name,
Eulogiated from the green decline
Of Thames’s banks to Scoticanian shores,
Where Lochlomondian liquids undulize.


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Post #19 Posted: Mon Dec 26, 2022 9:47 am 
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Speculatively:
Current position:
1. Upper left is open. I can't understand why that isn't the biggest. So I would like to take sente at the least with b. This makes W heavier behind B's line and also helps B work with a move in the upper left, preventing W sacrifice stones too deep in B's area. c isn't even necessarily sente. I'm not sure why that is there. hmm, I guess it is probably around 30 points to live, so I guess it is sente. In that case, I think a is the worst of the options.

Opp to play
1. Even first to play L17 seems risky after K15 but perhaps it is still better than K15. Not sure though.

Past:
1. Why did W even start the fight in the upper right moyo when the upper left was open? Presumably enticed by the space due to the low and small R15 and the O8 cut. I can't approve though. There is not much aji on R15. And O8 is locally a net. With the big lower right corner, this position feels as though it should be much better for W. B's several extra centre stones don't seem to be doing anything. W has around 48 pts there. On the other hand I'd say B has around 3 stones worth in the upper right and 1 in the lower left, with sente. That should be theoretically around 63 stones. Probably W living in the centre reduces this more than this estimate otherwise it would be too good for B. It seems that I have underestimated how many moves W spend on the lower side. Perhaps B really is better. Ah, but I was using territory counting for one and stone counting for the other, so that is probably the main reason for the discrepancy.

Check:
1. I think c is like a probe. There isn't much there beyond making a very large ko threat.

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