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 Post subject: Retraining the Neural Network in My Head - Part 2
Post #1 Posted: Thu Apr 08, 2021 6:10 am 
Dies with sente

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This post follows on from the "which side to play atari" post. It shows
situations where White needs to save one or more stones in atari. He must
choose to extend or capture. The White player (me) usually makes
the wrong choice according to KataGo.

Click Here To Show Diagram Code
[go]$$ 79 moves from file e-or-c-01-move080.
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . X , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . X . . X . |
$$ | . . . . . . . . . . . . . . . @ @ @ @ |
$$ | . . . . . . . . . . . . . X X @ X X @ |
$$ | . . . , . . . . . , . . . . O X . . X |
$$ | . . . . . . . . . . . X X . O X X X . |
$$ | . . . . . . . . . O X . X . O X W a . |
$$ | . . . . . . . . . X . X O X O O X O . |
$$ | . . . . . . . . O X X O O O O X X b . |
$$ | . . . . . . . . O O O X O X X O O . . |
$$ | . . . O . . . . . X O X X X O , O . . |
$$ | . . . . . . . . O O X . X O O . O . . |
$$ | . . . . . . . . . X . X . X . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

In the above diagram, the circled stone is in atari. I played at a,
but b is 8.9 points better according to Katago. I was worried about
the potential (indirect?) ko if Black replies to b at a, but
failed to notice that Black can gain a liberty in the capturing race after
White a by playing b himself, which gives Black a better squeeze
on the squared white stones.

Click Here To Show Diagram Code
[go]$$ 239 moves from file e-or-c-02-move240.
$$ ---------------------------------------
$$ | . X X . X . . . X O . . . . . X . . . |
$$ | . O O X . . X . X O X X X . X . X . . |
$$ | . . . O X X . X X O O X O X X . X . . |
$$ | . . . O . O X O X X O O O O X X X X . |
$$ | . . . O . O O O . O O . X O O X O O . |
$$ | . . X O X O X O O O . . X X O X O . . |
$$ | . O O O O X X X X O X O X O X X O . . |
$$ | O . O X O X . X O X X O O O O O . . . |
$$ | . O X . X . X . O . X X . . O . O O . |
$$ | O X X X X X X X O X W W a O . O . X . |
$$ | X . X O O X O O X X W X b . O X X . . |
$$ | . X O O . O O X X . X O . O . O X . . |
$$ | . O . . O . O O X c X d X . O O X X . |
$$ | . . O . . . O X O O O . X O . X . . X |
$$ | . . . . . X X X X O X X X O X . X X . |
$$ | . . . O . . X O O X X O O X . X X O O |
$$ | . . . . . X X O X X O X . X X O O O . |
$$ | . . . O O X O O O O O X . X O O . . . |
$$ | . . . O . O . O . . . . . . . . . . . |
$$ ---------------------------------------[/go]

In the above diagram, the marked stones are in atari. I played
a, but b is 0.8 points better according to Katago. That is a
significant difference this late in the game. The reason is that White b
forces Black c, which I had not noticed. If Black does not answer
b at c, White makes further gains by pushing in at d.

I often have trouble seeing what is what late in the game when the visual field
is busy, as here. This is true whether playing online or over the board.
Katago sees clearly and invites me to think.

Click Here To Show Diagram Code
[go]$$ 27 moves from file e-or-c-04-move028.
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . c . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . X , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . X X W b . |
$$ | . . . , . . . . . , . . . . . O X O . |
$$ | . . . . . . . . . . . . . . . . a . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X . O . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . X . X . . . |
$$ | . . . . . O . . . . . X . O X X O . . |
$$ | . . . . . . . . . . . . . . X O . O . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ ---------------------------------------[/go]

In the above diagram, the marked stone is in atari. I played a,
which is 1.5 points better than b. However, KataGo thinks that White c
is best here. (Even when you are right, you are still wrong.)

Click Here To Show Diagram Code
[go]$$ 101 moves from file e-or-c-05-move102.
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . b a . . . . . . . |
$$ | . . O . . . . . . O X W X . . . . . . |
$$ | . X . O . O . . O , O X . . X , X . . |
$$ | . . . . . . . . . . O X . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . X . . . . . . . . X . . . . . |
$$ | . . . . . . O . . . X . X . X O O . . |
$$ | . . . . . X O . . . . . . X O X X . . |
$$ | . . X , . X O . . O . X O . O O O . . |
$$ | . . . . . . X . O . . X O . . . . . . |
$$ | . . X O . . . . . . . . X O . . . . . |
$$ | . . X O . X . . O . X . X O . O X . . |
$$ | . . O O . . . . . . . . X X O . . . . |
$$ | . . . . . X . . O O O X . X X O O O . |
$$ | . . . O . . . X X X O X O O O X O X . |
$$ | . . . O . X . . X O . O X X X X X . . |
$$ | . . . . . . . . X O . O O X O X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

In the above diagram, the marked stone is in atari. I played a, but b
is 3.8 points better according to Katago. This shape often occurs on
the second and third lines, and I have noticed that strong players usually
capture the opponent's stone.

Click Here To Show Diagram Code
[go]$$ 29 moves from file e-or-c-06-move030.
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . X , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X X . . |
$$ | . . . , . . . . . , . . . . O O X . . |
$$ | . . . . . . . . . . . . . . O X X . . |
$$ | . . . . . . . . . . . . . . O X W a . |
$$ | . . . . . . . . . . . . . O . O X b . |
$$ | . . . . . . . . . . . . . X O . O . . |
$$ | . . . . . . . . . . . . . X X O O . . |
$$ | . . . O . . . . . , . . . . O X . X . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

In the above diagram, the marked stone is in atari. I played
a, but b is 2.4 points better according to Katago. The
situation is similar to that in the previous diagram.

Review

There is not enough material to draw any general conclusions. However,
accurate reading always helps, and one should probably capture any cutting
stone on the third line immediately if possible.

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 Post subject: Re: Retraining the Neural Network in My Head - Part 2
Post #2 Posted: Thu Apr 08, 2021 6:57 am 
Gosei

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thirdfogie wrote:
There is not enough material to draw any general conclusions. However, accurate reading always helps, and one should probably capture any cutting stone on the third line immediately if possible.

In these sorts of atari situations, I believe that in general stronger (let's say 1d) players are much more likely to just capture a stone, and weaker (let's say 5k) players are more likely to extend instead of taking the stone off the board, which looks more efficient but often leads to the opponent getting forcing moves later or having some aji still around. I think that it is a good instinct for players of our level to first consider making the capture, unless there is clearly zero aji.

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 Post subject: Re: Retraining the Neural Network in My Head - Part 2
Post #3 Posted: Thu Apr 08, 2021 7:34 am 
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To decide whether to extend or capture, I try to imagine the followup. Consider the following diagram.


Click Here To Show Diagram Code
[go]$$ 101 moves from file e-or-c-05-move102.
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . b a . . . . . . . |
$$ | . . O . . . . . . O X W X . . . . . . |
$$ | . X . O . O . . O , O X . . X , X . . |
$$ | . . . . . . . . . . O X . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . X . . . . . . . . X . . . . . |
$$ | . . . . . . O . . . X . X . X O O . . |
$$ | . . . . . X O . . . . . . X O X X . . |
$$ | . . X , . X O . . O . X O . O O O . . |
$$ | . . . . . . X . O . . X O . . . . . . |
$$ | . . X O . . . . . . . . X O . . . . . |
$$ | . . X O . X . . O . X . X O . O X . . |
$$ | . . O O . . . . . . . . X X O . . . . |
$$ | . . . . . X . . O O O X . X X O O O . |
$$ | . . . O . . . X X X O X O O O X O X . |
$$ | . . . O . X . . X O . O X X X X X . . |
$$ | . . . . . . . . X O . O O X O X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


If White plays at "a" then :b2: is forcing. :b4: plays elsewhere because any local move is gote, then White comes back later to play :w5: with sente.

Click Here To Show Diagram Code
[go]$$Wc White plays at a
$$ ---------------------------------------
$$ | . . . . . . . . . . . 7 5 6 . . . . . |
$$ | . . . . . . . . . . 3 1 2 8 . . . . . |
$$ | . . O . . . . . . O X W X . . . . . . |
$$ | . X . O . O . . O , O X . . X , X . . |
$$ | . . . . . . . . . . O X . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . X . . . . . . . . X . . . . . |
$$ | . . . . . . O . . . X . X . X O O . . |[/go]


If White plays at "b" then :b2: plays elsewhere, but then White has sente endgame moves.

Click Here To Show Diagram Code
[go]$$Wc White plays at b
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . 9 7 8 . . . |
$$ | . . . . . . . . . . 1 . 3 5 6 0 . . . |
$$ | . . O . . . . . . O X W X 4 . . . . . |
$$ | . X . O . O . . O , O X . . X , X . . |
$$ | . . . . . . . . . . O X . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . X . . . . . . . . X . . . . . |
$$ | . . . . . . O . . . X . X . X O O . . |[/go]

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 Post subject: Re: Retraining the Neural Network in My Head - Part 2
Post #4 Posted: Thu Apr 08, 2021 10:21 am 
Gosei

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jlt wrote:
If White plays at "b" then :b2: plays elsewhere, but then White has sente endgame moves.

Click Here To Show Diagram Code
[go]$$Wc White plays at b
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . 9 7 8 . . . |
$$ | . . . . . . . . . . 1 . 3 5 6 0 . . . |
$$ | . . O . . . . . . O X W X 4 . . . . . |
$$ | . X . O . O . . O , O X . . X , X . . |
$$ | . . . . . . . . . . O X . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . X . . . . . . . . X . . . . . |
$$ | . . . . . . O . . . X . X . X O O . . |[/go]

I believe that for this reason Black usually forces with :b2: first, since White won't be able to make as much progress with a in the following diagram:

Click Here To Show Diagram Code
[go]$$Wc Force first
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . 1 2 a . . . . . . |
$$ | . . O . . . . . . O X W X . . . . . . |
$$ | . X . O . O . . O , O X . . X , X . . |
$$ | . . . . . . . . . . O X . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . X . . . . . . . . X . . . . . |
$$ | . . . . . . O . . . X . X . X O O . . |[/go]

Confirmation or disagreement from stronger players would be appreciated!

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 Post subject: Re: Retraining the Neural Network in My Head - Part 2
Post #5 Posted: Thu Apr 08, 2021 10:30 am 
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I am not sure that :b2: in your diagram is forcing. It's big, but how big compared to the rest of the board, I don't know.

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 Post subject: Re: Retraining the Neural Network in My Head - Part 2
Post #6 Posted: Thu Apr 08, 2021 10:37 am 
Gosei

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Good point. I just asked KataGo now and it wants to first play the double sente sequence starting with E2, then come back and play my :b2:.

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 Post subject: Re: Retraining the Neural Network in My Head - Part 2
Post #7 Posted: Thu Apr 08, 2021 11:33 am 
Dies with sente

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It was the prospect of a ko if white plays elsewhere after :b2: that made me extend
instead of capturing during the game.

Click Here To Show Diagram Code
[go]$$Wc Force first
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . 1 2 a . . . . . . |
$$ | . . O . . . . . . O X W X . . . . . . |
$$ | . X . O . O . . O , O X . . X , X . . |
$$ | . . . . . . . . . . O X . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . X . . . . . . . . X . . . . . |
$$ | . . . . . . O . . . X . X . X O O . . |[/go]

Extending was clearly a mistake in this game because White is so strong to the left of the
potential ko that he has nothing to fear from Black starting it. In the general case, it
feels burdensome to have to evaluate a potential ko before making the "extend or capture"
decision, so I will adopt the "Ape stronger players" policy and hope to learn by
experience if any exceptions do appear.

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 Post subject: Re: Retraining the Neural Network in My Head - Part 2
Post #8 Posted: Thu Apr 08, 2021 1:54 pm 
Lives with ko

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Click Here To Show Diagram Code
[go]$$Wc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . X , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . X 6 4 X . |
$$ | . . . . . . . . . . . . . . . @ @ @ @ |
$$ | . . . . . . . . . . . . . X X @ X X @ |
$$ | . . . , . . . . . , . . . . O X . . X |
$$ | . . . . . . . . . . . X X . O X X X 7 |
$$ | . . . . . . . . . O X . X . O X W 1 8 |
$$ | . . . . . . . . . X . X O X O O X O 5 |
$$ | . . . . . . . . O X X O O O O X X 2 0 |
$$ | . . . . . . . . O O O X O X X O O 3 . |
$$ | . . . O . . . . . X O X X X O , O . . |
$$ | . . . . . . . . O O X . X O O . O . . |
$$ | . . . . . . . . . X . X 9 X . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

This ko is difficult, it's certainly a gain for black in terms of points. Perhaps white 5 is premature here.
The difference is to go from winning the race with the T8 tesuji to pretty much losing the capture race. White is lucky to have such a big ko threat to prevent collapse.
Black already has an eye, so just needs to prevent white from approaching the outside liberty (it acts like a temporary eye, and two 'eyes' is all you need).
Still, admittedly black has worryingly little on the rest of the board, and P16 is overconcentrated.


Click Here To Show Diagram Code
[go]$$Wc
$$ ---------------------------------------
$$ | . X X . X . . . X O . . . . . X . . . |
$$ | . O O X . . X . X O X X X . X . X . . |
$$ | . . . O X X . X X O O X O X X . X . . |
$$ | . . . O . O X O X X O O O O X X X X . |
$$ | . . . O . O O O . O O . X O O X O O . |
$$ | . . X O X O X O O O . . X X O X O . . |
$$ | . O O O O X X X X O X O X O X X O . . |
$$ | O . O X O X . X O X X O O O O O . . . |
$$ | . O X . X . X . O . X X . . O . O O . |
$$ | O X X X X X X X O X W W 1 O . O . X . |
$$ | X . X O O X O O X X W X . . O X X . . |
$$ | . X O O . O O X X . X O 5 O . O X . . |
$$ | . O . . O . O O X 4 X 3 X 2 O O X X . |
$$ | . . O . . . O X O O O 6 X O . X . . X |
$$ | . . . . . X X X X O X X X O X . X X . |
$$ | . . . O . . X O O X X O O X . X X O O |
$$ | . . . . . X X O X X O X . X X O O O . |
$$ | . . . O O X O O O O O X . X O O . . . |
$$ | . . . O . O . O . . . . . . . . . . . |
$$ ---------------------------------------[/go]

This seems to be the main problem. I'm surprised that the difference is so small.
Now it looks like white has a tesuji to play d to prevent :b2: in sente, but it might not gain and also black can still respond at :b4:.
White makes 4 points in the region at b like this but there is a 5 point move left open at :b2:. Lets count it as 4 - (5/2)=1.5 in the usual way.
(edit: the :w3: :b4: :w5: :b6: sequence is questionable as white can use black's shortage of liberties around E5 instead.)
In the game, we can expect black to play c eventually in sente and white defends at :b2: (note black has to capture the cutting stones at c eventually so playing d is pointless). So white has one point at B, an extra half point at a, and in most variations another half point which either comes from playing N8 or getting forcing moves around E5. That's 2 points.
So the difference really is pretty small locally. Globally, perhaps b makes it harder for B to hane at A18, but my feeling is that though black has ko threats at A7 and E3 they aren't big enough since F17 will die at the end of the ko. There is also the big move at E5 which seems around 4 points also, but no other very big moves (A11 is B's right).
At this stage of the game, adding a new 5 point move for your opponent to attack your position is often very bad, but when there is only one big move left, at E5 of similar size, it might actually make your move a good move in order to fight for tedomari. I can't see any move bigger than two points other than those I've already mentioned.
My understanding is that this position is a bit unusual and your move at a is a good trick move. If black plays in the normal way to punish directly as in the above diagram, you get the last big point at E5 and I think you have made a gain. 4-5+4-2/4 > 2-4+2/4 (the 2 in the 2/4 is if the next biggest endgame is 2 points).
However, my guess is that black should patiently take a two points reverse sente by playing as below. This way black gets tedomari.
Click Here To Show Diagram Code
[go]$$Wc
$$ ---------------------------------------
$$ | . X X . X . . . X O . . . . . X . . . |
$$ | . O O X . . X . X O X X X . X . X . . |
$$ | . . . O X X . X X O O X O X X . X . . |
$$ | . . . O . O X O X X O O O O X X X X . |
$$ | . . . O . O O O . O O . X O O X O O . |
$$ | . . X O X O X O O O . . X X O X O . . |
$$ | . O O O O X X X X O X O X O X X O . . |
$$ | O . O X O X . X O X X O O O O O . . . |
$$ | . O X . X . X . O . X X . . O . O O . |
$$ | O X X X X X X X O X W W 1 O . O . X . |
$$ | X . X O O X O O X X W X 3 . O X X . . |
$$ | . X O O . O O X X . X O 2 O . O X . . |
$$ | . O . . O . O O X 4 X . X 5 O O X X . |
$$ | . . O . . . O X O O O . X O . X . . X |
$$ | . . . . 6 X X X X O X X X O X . X X . |
$$ | . . . O . . X O O X X O O X . X X O O |
$$ | . . . . . X X O X X O X . X X O O O . |
$$ | . . . O O X O O O O O X . X O O . . . |
$$ | . . . O . O . O . . . . . . . . . . . |
$$ ---------------------------------------[/go]

I'm not that confident about the size of E5 though.


next diagram - interesting. Difficult problem.
next diagram - explained very well by others. Even if black were solid elsewhere on the board, I would be very reluctant to sacrifice the chance to get into black's upper right corner just to avoid a (medium size) ko that black has to spend 2 moves to start. The ko isn't that small, but black is so thin in the upper right. In this game, black's shape on the left seems to have some problems and some ko threats, or at least threats to set up ko threats (in order to profit), or to get endgame such as E2.

Click Here To Show Diagram Code
[go]$$Wc
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . X , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . X X . . |
$$ | . . . , . . . . . , . . . . O O X . . |
$$ | . . . . . . . . . . . . . . O X X 2 . |
$$ | . . . . . . . . . . . . . . O X W 1 . |
$$ | . . . . . . . . . . . . . O . O X 3 . |
$$ | . . . . . . . . . . . . . X O . O . . |
$$ | . . . . . . . . . . . . . X X O O 4 . |
$$ | . . . O . . . . . , . . . . O X . X . |
$$ | . . . . . . . . . . . . . . . X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

This is the main local sequence I am worried about from playing a. Black is getting thicker on both sides and can preserve several ko threats. If you capture at b, black has no forcing moves, and by attacking black, you may be able to S9 yourself in sente, or attack more strongly with O3.
The only draw back of b is of course the potential for black to play S8. However, this is risky for black, and in the worst case white can just connect and still be alive locally. Most of the time, W can be flexible and tenuki. B has to add a move at R7, and white still has the option to make ko for life locally. Even if B adds another move at R8 ending the ko, white still can make an eye with S5. If B tries to take with S6 instead of R8, this seems crazy because if white wins the ko, S6 becomes a wasted move, and if black wins, black has to add yet another move in such a small area.


Last edited by dhu163 on Sun Apr 11, 2021 8:24 am, edited 1 time in total.

This post by dhu163 was liked by 2 people: dfan, thirdfogie
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 Post subject: Re: Retraining the Neural Network in My Head - Part 2
Post #9 Posted: Fri Apr 09, 2021 6:40 am 
Oza

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An interesting exercise.

Quote:
The White player (me) usually makes the wrong choice according to KataGo.


Have you got any inkling as to why this bias may be so. E.g. did someone give you bum information in the past, or did you lack playing over enough pro games (i.e. you did not previously train your neural network on the basis of pro games)? Or perhaps there are other psychological factors, such a being more concerned with depriving the opponent of something rather than attending to your own concerns? (I happen to believe this last point is something that applies to ALL amateur play.)


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 Post subject: Re: Retraining the Neural Network in My Head - Part 2
Post #10 Posted: Sat Apr 10, 2021 1:39 am 
Dies with sente

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Thanks to everyone who commented.

John Fairbairn

It feels like the mistakes spring from the last of your causes: giving too
little priority to weaknesses in my own positions. I haven't played over
any professional games on a real board since September 2013, when my wife
was away for a month. Watching professional games online is clearly not
the same thing.

We are told that passive play is a sure road to defeat, and it may be that
I take that advice too simplistically. Sometimes, "reculer pour mieux sauter"
should be the motto. Or one could simply blame egotism.

dhu163

Thanks for the detailed analyses. I am amazed that anyone could apply end-game
mathematics to the game shown below, given that he must first identify all the
candidate sequences. On the other hand, people have composed great music using
six-part counterpoint and performed highly abstract mathematics in a way which
makes me gasp for breath, so what do I know? The diagram shows KataGo's best moves
following White's mistake. Model b40c256-s6485784576-d1573360039 was used
with about 30,000 visits per move, though the number of visits seems to make
little difference this late in the game. White has a lead of about 11 points,
but KataGo still picks the mathematically best moves as far as I can tell.

Click Here To Show Diagram Code
[go]$$ File e-or-c-02-move240 continued by KataGo
$$ ---------------------------------------
$$ | . X X . X . . . X O . . . . . X . . . |
$$ | . O O X . . X . X O X X X . X . X . . |
$$ | . . . O X X . X X O O X O X X . X . . |
$$ | . . . O . O X O X X O O O O X X X X . |
$$ | . . . O . O O O . O O . X O O X O O . |
$$ | . . X O X O X O O O . . X X O X O . . |
$$ | . O O O O X X X X O X O X O X X O . . |
$$ | O 0 O X O X . X O X X O O O O O . . . |
$$ | 9 O X . X . X . O . X X . . O . O O 4 |
$$ | O X X X X X X X O X O O O O . O . X . |
$$ | X . X O O X O O X X O X . . O X X . . |
$$ | . X O O . O O X X . X O . O 6 O X . . |
$$ | . O . . O . O O X . X . X 1 O O X X . |
$$ | . . O . . 3 O X O O O . X O 5 X . . X |
$$ | . . . . 2 X X X X O X X X O X . X X . |
$$ | . . . O . . X O O X X O O X . X X O O |
$$ | . . . 8 7 X X O X X O X . X X O O O . |
$$ | . . . O O X O O O O O X . X O O . . . |
$$ | . . . O . O . O . . . . . . . . . . . |
$$ ---------------------------------------[/go]

In the actual game, black played 1 and I replied with a grotesque self-atari
(white at black 5). After that, I was lucky to win by 2 points.


In the following game, my original comment on the situation was wrong.
I should have analysed more with KataGo before posting. The continuation
is what actually happened. Black's terrible mistake at 5 may be
instructive for some.
Click Here To Show Diagram Code
[go]$$ Actual game from file e-or-c-01-move080
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . . . . . , . . . . X , X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . X 5 1 X . |
$$ | . . . . . . . . . . . . . . . O O O O |
$$ | . . . . . . . . . . . . . X X O X X O |
$$ | . . . , . . . . . , . . . . O X 3 2 X |
$$ | . . . . . . . . . . . X X . O X X X 6 |
$$ | . . . . . . . . . O X . X . O X O O 4 |
$$ | . . . . . . . . . X . X O X O O X O . |
$$ | . . . . . . . . O X X O O O O X X . . |
$$ | . . . . . . . . O O O X O X X O O . . |
$$ | . . . O . . . . . X O X X X O , O . . |
$$ | . . . . . . . . O O X . X O O . O . . |
$$ | . . . . . . . . . X . X . X . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

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 Post subject: Re: Retraining the Neural Network in My Head - Part 2
Post #11 Posted: Sat Apr 10, 2021 3:09 am 
Oza

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Quote:
We are told that passive play is a sure road to defeat, and it may be that
I take that advice too simplistically. Sometimes, "reculer pour mieux sauter"
should be the motto. Or one could simply blame egotism.


This interests me because it is a language thing rather than a maths thing. Without getting into Sapir-Whorf arguments I do believe there is a link between language and actions.

The reason this particular post of yours interests me is that you say someone has been telling you that passive play is to be avoided. But who? I've racked my brains but I can't recall the word passive being used in oriental texts. Very occasionally there are words that tend in that direction (e.g. "negative"), but these are very occasional, and my gut feeling is that such comments are applied to beginners far, far more than to stronger players.

But, in contrast, what I notice is ultra-common in pro talk are references to timing.

To be specific, if we take the atari on the outside and the atari on the inside in your first example, what came over to me was an attempt to say one is better than the other in some static way. In your case this may be because you apparently perceive one as potentially aggressive or passive, but I could easily imagine others may say it's a matter of good and bad shape, for example.

However, my impression from pro talk is that neither is better or worse than the other in such terms. Nor is it, perhaps strangely, a matter of reading. Rather, it is a matter of timing. We can infer this from the fact there are so many comments of the type "Black should first play A, then B". In other words, purely in shape terms B is not at all inferior - it's just inferior at this particular moment in terms of timing. Furthermore, this can be but does not have to be the same as gote no sente (or reculer pour mieux sauter). That is, timing issues are pervasive - they are not just honte moments.

As some mild proof of that, I used Kombilo to check the position of two different-coloured ikken-tobis side by side with one side wedging between the opposing ikken. Kombilo came up with lots of examples in the 110,000-game GoGo database - and the inside and outside ataris as played by pros came up exactly even!

In short, I think we vastly overate shape and underestimate timing in go. It may be time to revisit Juergen Mattern's Der richtige Zeitpunky? It's a very long time since I read that and I can't remember what's in it. Does anyone have a more recent memory?

But, in general, what do you think of exploring the notion of timing more.

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 Post subject: Re: Retraining the Neural Network in My Head - Part 2
Post #12 Posted: Sat Apr 10, 2021 2:36 pm 
Judan

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John Fairbairn wrote:
Quote:
We are told that passive play is a sure road to defeat, and it may be that
I take that advice too simplistically. Sometimes, "reculer pour mieux sauter"
should be the motto. Or one could simply blame egotism.


<snip>
But, in contrast, what I notice is ultra-common in pro talk are references to timing.


I think the relative abundance of discussions on timing in pro commentaries in pro games, does not necessarily mean it should be of the same abundance and importance in commentaries on kyu games. Kyus make gross mistakes (chief categories being massive underplays aka passive play, and also massive overplays / over-aggression) that pros left behind many years ago when still little kids. So of course pros aren't going to be talking about things like wasting a move to live with a group that was already alive, or how to kill a bulky 5, or not playing a 2 point move in the opening when there are 30 point moves up for grabs, because that's super easy and obvious for them. Timing is one of the more advanced topics which they can still get wrong and differ in opinions, so they talk about it more.
This is not to discourage more talk of timing here, it's a fascinating topic and indeed one of my favourite books "Beyond forcing moves" could be subtitled "the importance of timing". Here's a thread about a critical timing issue in a common post-joseki joseki https://lifein19x19.com/viewtopic.php?f=17&t=5150.

I find it interesting that thirdfogie says he was trying to avoid passive play as his justification for the extend here (or maybe in general and not this example?):
Click Here To Show Diagram Code
[go]$$Wc 101 moves from file e-or-c-05-move102.
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . 1 . . . . . . . |
$$ | . . O . . . . . . O X W X . . . . . . |
$$ | . X . O . O . . O , O X . . X , X . . |
$$ | . . . . . . . . . . O X . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . X . . . . . . . . X . . . . . |
$$ | . . . . . . O . . . X . X . X O O . . |
$$ | . . . . . X O . . . . . . X O X X . . |
$$ | . . X , . X O . . O . X O . O O O . . |
$$ | . . . . . . X . O . . X O . . . . . . |
$$ | . . X O . . . . . . . . X O . . . . . |
$$ | . . X O . X . . O . X . X O . O X . . |
$$ | . . O O . . . . . . . . X X O . . . . |
$$ | . . . . . X . . O O O X . X X O O O . |
$$ | . . . O . . . X X X O X O O O X O X . |
$$ | . . . O . X . . X O . O X X X X X . . |
$$ | . . . . . . . . X O . O O X O X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


I would characterise this mistake as being passive! To illustrate, with a simple tewari: white instead captures at 1, black descends at 2, white then answers at 3, kindly giving black the large endgame move at 2 in sente. 3 is, I think we can all agree, terribly passive, much better to tenuki and play elsewhere. But by extending at 3 first, this is the result you get.

Click Here To Show Diagram Code
[go]$$Wc 101 moves from file e-or-c-05-move102.
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . 1 3 2 . . . . . . |
$$ | . . O . . . . . . O . W X . . . . . . |
$$ | . X . O . O . . O , O X . . X , X . . |
$$ | . . . . . . . . . . O X . . . . . . . |
$$ | . . X . . . . . . . . . . . . . . . . |
$$ | . . . . X . . . . . . . . X . . . . . |
$$ | . . . . . . O . . . X . X . X O O . . |
$$ | . . . . . X O . . . . . . X O X X . . |
$$ | . . X , . X O . . O . X O . O O O . . |
$$ | . . . . . . X . O . . X O . . . . . . |
$$ | . . X O . . . . . . . . X O . . . . . |
$$ | . . X O . X . . O . X . X O . O X . . |
$$ | . . O O . . . . . . . . X X O . . . . |
$$ | . . . . . X . . O O O X . X X O O O . |
$$ | . . . O . . . X X X O X O O O X O X . |
$$ | . . . O . X . . X O . O X X X X X . . |
$$ | . . . . . . . . X O . O O X O X . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]


So the only reason to not capture for 1, is if you think black won't play descend for 2, but will play the atari for a ko and you don't like that.

Quote:
It was the prospect of a ko if white plays elsewhere after :b2: that made me extend
instead of capturing during the game.


But if you are scared of ko don't play go! as the saying goes. So I would actually say the descend is more accurately described not as avoiding passive play, but avoiding a scary looking ko (which stronger players know isn't scary, because wimping out of that ko is admitting defeat without a fight).

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 Post subject: Re: Retraining the Neural Network in My Head - Part 2
Post #13 Posted: Sun Apr 11, 2021 5:29 am 
Lives with ko

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Quote:
I am amazed that anyone could apply end-game
mathematics to the game shown below, given that he must first identify all the
candidate sequences.


Its late enough in the game that I think CGT theorists could solve it perfectly with some time and maybe a computer. As for me:

Well, the KG diagram means I got it wrong all over the place. I haven't put in enough study of the endgame myself and I'm learning here too. I normally only use approximations, which is insufficient for accuracy on the whole board. But there are also several things I still don't understand with KG's diagram.

I didn't notice the tesuji that means :w4: is big. The tesuji is black can play two spaces above :w4: , that gains around 1 1/3 in sente or 4 in gote with a crude atari. The fact there is this big move breaks my argument already.
I didn't notice black could clamp in the upper left gaining around 1 2/3 in sente locally, but a bit less as it concerned the ko to the right of it.
White connecting in the centre is a 2 point reverse sente, so isn't immediately clear why :w4: is better (or perhaps it is just a matter of style and both are fine).
The descent in the lower right is also big, and as far as I can tell black hane is 3 to 4 points in gote.

I guess there isn't much point for black to take a reverse sente when white can also take a reverse sente, so my logic for my diagram was wrong.

E5 still seems hard to evaluate. Because even after the :w2: :b3: exchange in your diagram, the next move is still pretty big, 3 points gote at E6.

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 Post subject: Re: Retraining the Neural Network in My Head - Part 2
Post #14 Posted: Sun Apr 18, 2021 2:18 am 
Dies with sente

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This post is to tidy up some loose ends and act as a reference if I ever need to revisit
the topics.

dhu63
Quote:
I didn't notice the tesuji that means :w4: is big. The tesuji is black can play
two spaces above :w4:

My opponent found :w4: during the game. He has started looking for moves like
this on the first line.

John Fairbairn
Quote:
I used Kombilo to check the position of two different-coloured ikken-tobis
side by side with one side wedging between the opposing ikken. Kombilo came up
with lots of examples in the 110,000-game GoGo database - and the inside and outside
ataris as played by pros came up exactly even!

Thanks for checking with Kombilo. Your results were salutary. One difference
is that my opponent plays the wedge when it is a bad move. The
professional-standard moves you examined would presumably not be giving the
opponent a chance to make a big gain.

Quote:
The reason this particular post of yours interests me is that you say someone
has been telling you that passive play is to be avoided. But who? I've racked
my brains but I can't recall the word passive being used in oriental texts.
Very occasionally there are words that tend in that direction (e.g.
"negative"), but these are very occasional, and my gut feeling is that such
comments are applied to beginners far, far more than to stronger players.

You perhaps inferred too much. My word "simplistically" should have been
"idiotically". The kind of advice I had in mind is "Do not follow
the opponent around the board" and "If the opponent plays a so-called
double-sente move, look for a similar move you can play elsewhere". No doubt
both rules are too simple as stated, but I have certainly found them useful. I
cannot read oriental texts, so cannot quote original professional-level
material if that is what you were asking for. Yoon YoungSun does have a recent
post (https://www.youtube.com/watch?v=8LrJF6huDso) with the strap-line
"Effective and Aggressive Haengma", where she discusses responses to an
opponent's peep. She is really explaining efficient responses, but the word
"aggressive" is there, alongside a cartoon crocodile.

Be that as it may, John's reply prompted a wider survey on my side. A search
of 64 older games against the same opponent were found to contain 26 wedge moves
by him and 7 by me. Details of the search are hidden below.

Kombilo is available for Linux. It built according to the
instructions at https://dl.u-go.net/kombilo/doc/manual.html#linux, but the
result did not run on Debian Bullseye. So I wrote some custom code to do the
searching. Writing the code needed decisions on exactly which moves count as
wedges. The diagram shows the rules used for the purposes of this exercise.
As usual, rotations, reflections and colour reversals do not change the results.

Click Here To Show Diagram Code
[go]$$ What is a wedge anyway?
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . X . |
$$ | . . O . . . X X . . O O . X X . . X . |
$$ | . . B , . . W . . , B . . . W , . W . |
$$ | . . O . . . X . . O O . . X X . . X . |
$$ | . . . . . . . . . . . . . . . . . X . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . O X , . . O X O , . O O O . O O O . |
$$ | . a W . . . . W . . . . B . . . B . . |
$$ | . O X . . . O X . . . O O . . O O O . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . X . . . . . . |
$$ | . . . , . . . . X . . X O X . . . O . |
$$ | X . . . . . . X W X . O B O . . X W X |
$$ | W . . . . . . . . . . . . . . . . . . |
$$ | X . . O B O . . b . . . c . . . . d . |
$$ ---------------------------------------[/go]

All the marked stones along the top of the diagram were treated as wedges.

The marked stone on the middle of the left side is a wedge, but not of interest
because Black is unlikely to play at a. The other marked stones in the
middle row are not regarded as wedges because an enemy stone is placed in
atari or the move is more likely to be nakade.

At the bottom, the marked moves on the edge of the board are classed as
throw-ins rather than wedges. The same is true of the marked stone above b.
The marked stone above c is not counted as a wedge because it
captures an enemy stone. The marked stone above d is not a wedge
because it is in contact with a friendly stone

In the 64 games examined, there were 26 wedge moves by him and 7 by me.
All but 2 wedges were bad according to KataGo. It would be too much work to
make a diagram for all of them, and one should not spam the forum with
examples of bad play. Excruciating details are hidden below.

jc-tf-14-dec-2020.sgf black 87. Wedge lost 6.7, reply good outside, difference 6.9.
tf-jc-04-nov-2020-game-2.sgf black 113. Wedge lost 12.8, reply good, no outside, difference 5.4.
tf-jc-07-dec-2020-game-1.sgf black 35. Wedge lost 1.5, reply good outside, difference 1.8.
tf-jc-07-dec-2020-game-2.sgf black 77. Wedge lost 6.7, reply good outside, difference 6.9.
tf-jc-08-feb-2021-game-1.sgf white 160. Wedge lost 4.1, reply good, no outside, difference 1.2. I wedged.
tf-jc-11-jan-2021-game-2.sgf black 107. Wedge lost 4.3, reply bad outside, difference 4.2.
tf-jc-16-nov-2020-game-1.sgf black 133. Wedge lost 1.9, reply good outside, difference 0.1.
tf-jc-16-nov-2020-game-2.sgf white 146. Wedge lost 3.7, reply good inside, difference 1.1.
tf-jc-19-oct-2020-game-2.sgf black 59. Wedge lost 7.0, reply good outside, difference 5.6.
tf-jc-23-nov-2020-game-1.sgf black 33. Wedge lost 4.4, reply bad outside, difference 0.4.
tf-jc-23-nov-2020-game-2.sgf black 105. Wedge lost 4.8, reply good outside, difference 4.2.
tf-jc-23-nov-2020-game-2.sgf white 186. Wedge lost 0.0, reply good outside, difference 0.5. I wedged.
tf-jc-25-jan-2021-game-1.sgf black 47. Wedge lost 6.1, reply good, no outside, difference 6.7.
tf-jc-30-nov-game-2.sgf black 65. Wedge lost 3.9, reply bad outside, difference 6.4.
Tf-Jc-07-sep-20-game-2.sgf black 57. Wedge lost 2.1, reply good outside, difference 0.6.
Tf-Jc-07-sep-20-game-2.sgf black 141. Wedge lost 0.6, reply good outside, difference 12.1. Obvious.
Tf-Jc-100.sgf black 59. Wedge lost 4.6, reply good inside, difference 1.3.
Tf-Jc-104.sgf white 26. Wedge lost 1.1, reply bad inside, difference 1.4. I wedged.
Tf-Jc-13-july-2020a.sgf black 49. Wedge lost 6.2, reply good outside, difference 12.9. Obvious.
Tf-Jc-13-july-2020b.sgf white 74. Wedge lost 3.3, reply good outside, difference 4.2. I wedged. All moves bad.
Tf-Jc-14-sep-2020-game-1.sgf black 59. Wedge lost 5.1, reply bad inside, difference 6.0.
Tf-Jc-14-sep-2020-game-2.sgf black 95. Wedge lost 2.6, reply good outside, difference 5.1.
Tf-Jc-2-07-jul-22020b.sgf black 39. Wedge lost 3.2, reply good outside, difference 9.5.
Tf-Jc-21-sep-2020-game-1.sgf white 84. Wedge lost 0.0, reply good, no outside, difference 0.1. I wedged.
Tf-Jc-21-sep-2020-game-1.sgf black 127. Wedge lost 3.5, reply good outside, difference 0.6.
Tf-Jc-21-sep-2020-game-2.sgf black 17. Wedge lost 0.7, reply good inside, difference 1.6.
Tf-Jc-21-sep-2020-game-2.sgf white 56. Wedge lost 0.5, reply good outside, difference 6.2. I wedged. Obvious.
Tf-Jc-aug-03a.sgf white 44. Wedge lost 4.7, reply good outside, difference 10.5. I wedged. Obvious-ish.
Tf-Jc-aug-03b.sgf black 31. Wedge lost 0.4, reply bad inside, difference 1.1.
Tf-Jc-aug-10-2020a.sgf black 71. Wedge lost 2.6, best reply is not an atari.
Tf-Jc-jul-07-2020.sgf black 91. Wedge lost 4.6, reply bad inside, difference 2.1.

File names were adjusted for brevity.

Of the 23 non-obvious cases where my opponent wedged, 7 of my replies were
wrong and 16 were right. One reason I did better against this collection of
wedges than in the original 4, is that 7 wedges in the second set happened in
shapes that are familiar from joseki or middle-game joseki, and all my replies
were correct in those cases. (I know very few joseki but my opponent
makes a virtue of knowing none.)

Of the same 23 cases, the "outside" move was correct in 13 cases, the "inside"
move was correct in 9 cases. In the other 2 cases, it was not possible to say
which side was "outside". Taken together with the 4 cases in the original
post, there may yet be some value in my original idea that "playing the
outside atari" is often better against this particular opponent. My
idea of "outside" is a vague blend of "towards the centre of the board" and
"away from the opponent's strength".

In the 7 cases where I wedged, 2 were correct. In 2 of the other 5, the best
move for white was actually a clamp. That discovery alone justifies the
exercise.

I don't regret spending time on the research, but it has now been overtaken by
events. My opponent has access to these findings and has stopped playing
wedges. He now favours lots of invasions on the first line, which are easier
to read out. Meanwhile, I am blundering away won games by not counting
liberties when tired near the end of the game. It is unclear how to cure that
ill.

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 Post subject: Re: Retraining the Neural Network in My Head - Part 2
Post #15 Posted: Sun Apr 18, 2021 5:18 am 
Dies in gote

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thirdfogie wrote:
I don't regret spending time on the research, but it has now been overtaken by
events. My opponent has access to these findings and has stopped playing
wedges. He now favours lots of invasions on the first line, which are easier
to read out. Meanwhile, I am blundering away won games by not counting
liberties when tired near the end of the game. It is unclear how to cure that
ill.


Maybe you need to retrain your neural network to play so as to win games early and decisively.

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 Post subject: Re: Retraining the Neural Network in My Head - Part 2
Post #16 Posted: Sun Apr 18, 2021 5:39 am 
Lives in sente
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Even pros are not immune to that disease: https://lifein19x19.com/viewtopic.php?p=233171#p233171

In principle, one way to avoid that kind of accident is, at every stage of the endgame, read what happens when the opponent pushes in every hole, makes all possible ataris and fills all liberties. But that's theory...

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 Post subject: Re: Retraining the Neural Network in My Head - Part 2
Post #17 Posted: Sun Apr 18, 2021 6:02 pm 
Honinbo

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thirdfogie wrote:
In the 7 cases where I wedged, 2 were correct. In 2 of the other 5, the best move for white was actually a clamp. That discovery alone justifies the exercise.


Very good. :)

thirdfogie wrote:
I don't regret spending time on the research, but it has now been overtaken by events. My opponent has access to these findings and has stopped playing wedges. He now favours lots of invasions on the first line, which are easier to read out. Meanwhile, I am blundering away won games by not counting liberties when tired near the end of the game. It is unclear how to cure that ill.


It doesn't hurt to start with the straightforward approach. Always count liberties. Even if that means doing less reading in the early and middle game. As a result you may make worse plays from time to time. But you won't throw away games from miscounting liberties late in the game. My guess is that you will win more games. :)

In addition, practice makes perfect. Your skill at counting liberties will improve, and will probably take less time as you get better at it. :)

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Everything with love. Stay safe.

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 Post subject: Re: Retraining the Neural Network in My Head - Part 2
Post #18 Posted: Tue Jul 13, 2021 4:45 pm 
Lives with ko

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Just had some thoughts on Uberdude's point about passive play. My thoughts are about defining such human concepts in terms of shape.

A definition of "passive" vs aggressive (or vs active) is probably about taking less risk with your own groups by playing close to them for safety, prioritising reinforcement as opposed to impact on the opponent or unoccupied areas). It is fairly independent of the component of quality/size of a move. But when it is a criticism, it generally means the opponent profits from it, either by taking a bigger move globally (since you didn't need to defend yet) or taking advantage locally. This case can be said to be that the descent allows black to seal off the upper right in sente, so the exchange seems timid.

Here I think thirdfogie describes the capture as passive since it removes the chance of the cutting stone escaping. Whereas descending plays more close to Black's area, which seems more confrontational at first sight. However, with some reading (since black playing on White's liberty shortage of L16 seems much less likely that using the N18 sente immediately), there is no chance of the cutting stone escaping if white plays descend.

In fact, compared to capturing, descending adds a second buffer zone between the cutting stone and Black's upper right (other than the capture move) making it more difficult for black to encroach.

Unfortunately this protection comes at a heavy price, namely the cost of another move given that white is forced to capture the stone anyway pretty much immediately.

Uberdude prefers to say the direct capture is not as passive. This is because the main line risks a ko, simply because Black's atari on the ko shape is not sente.

I'm sure this distinction between types of passiveness recurs throughout Go. It is related to concepts of gote no sente or sente no gote, or whether to defend a shape with one move or two.

.

Can this sort of analysis be done with other common words, such as light/heavy?

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