Life In 19x19

Posted: **Mon Mar 29, 2021 2:00 am**

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

After the marked black move White can make the natural answer at ''a'', flatten Black's moyo while attacking the lower right group with ''b'' or play ''c''. Which one is better?

Posted: **Tue Mar 30, 2021 5:30 am**

I don't know how to treat this kind of question but I'll say something, hoping that someone will give a better response. First I don't like "c", I think the moyo in the bottom has more potential than the top right, so I have to decide between "a" and "b". I compare White playing in one area and Black in the other and vice-versa.

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

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

Which one do I prefer?... I don't know. Maybe the second diagram because Black's moyo in the first diagram looks pretty big. But I am not sure!

Posted: **Tue Mar 30, 2021 7:30 am**

I like the lower side, too, but I'm still not sure if 'b' is the best move there. I'd be more inclined to play the keima there. How does Black respond? What happens if Black cuts 'b'?

Posted: **Thu Apr 01, 2021 2:16 am**

"Solution"

Click Here To Show Diagram Code: [go]$$W Mistake $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . O . O . O . . X . . . O O . . | $$ | . . O O X . . X . . O X X O O X O . . | $$ | . . O X X . X . . O O O X X . X O O . | $$ | . . . . . . . O . O . X . . . X X X . | $$ | . . O . . . . . O X O . . . . . . . . | $$ | . . . . X . . X X X X . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . 2 . . . . . . . . . . . . X . . | $$ | . . 3 O B . . . . , . . . . . c . . . | $$ | . . O X . . . . . . . . . . . . . . . | $$ | . . O . X . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . O X X . . . . . . . . . . . . O . . | $$ | . O O X . . . . . . . . . . . X O . . | $$ | . O X O . . . . . 4 . 1 . O O O . O . | $$ | . . X X X . . . . . . 5 X . X X O . O | $$ | . . . . . . . . . . . . 6 . X . X O . | $$ | . . . . . . . . . . . . . . . X . . . | $$ ---------------------------------------[/go]

I played

. Whether

is forcing or not can be debated, but assuming it is, then

still builds a decent moyo and Black's lower right group can still live.

Click Here To Show Diagram Code: [go]$$W Proper move $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . O . O . O . . X . . . O O . . | $$ | . . O O X . . X . . O X X O O X O . . | $$ | . . O X X . X . . O O O X X . X O O . | $$ | . . . . . . . O . O . X . . . X X X . | $$ | . . O . . . . . O X O . . . . . . . . | $$ | . . a . X . . X X X X . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . 1 . . . . . . . . . . . . X . . | $$ | . . . O B . . . . , . . . . . . . . . | $$ | . . O X . . . . . . . . . . . . . . . | $$ | . . O . X . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . O X X . . . . . . . . . . . . O . . | $$ | . O O X . . . . . c . 2 . . . X O . . | $$ | . O X O . . . . . . . . . O O O . O . | $$ | . b X X X . . e . . d . X . X X O . O | $$ | . . . . . . . . . . . . . . X . X O . | $$ | . . . . . . . . . . . . . . . X . . . | $$ ---------------------------------------[/go]

makes a big difference on the left side. Black can't destroy the potential easily with "a" because of the aji of his upper group.

can expand but the moyo can be reduced by "b" or "c" or even invaded at "d", using the aji of the lower right group.

Posted: **Thu Apr 01, 2021 5:20 am**

Your proper move strikes me as proper from the perspective of AI, who can easily find a living sequence while invading a moyo. I'm not sure a human can as easily deal with moyos (at least not me).

Also, maybe you can consider reporting what KataGo says the point gain/loss differential is in the various move considerations.

Anyway, I'm enjoying this series.

Posted: **Thu Apr 01, 2021 8:11 am**

Click Here To Show Diagram Code: [go]$$W Proper move $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . O . O . O . . X . . . O O . . | $$ | . . O O X . . X . . O X X O O X O . . | $$ | . . O X X . X . . O O O X X . X O O . | $$ | . . . . . . . O . O . X . . . X X X . | $$ | . . O . . . . . O X O . . . . . . . . | $$ | . . a . X . . X X X X . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . 1 2 . . . . . . . . . . . X . . | $$ | . . . O B . . . . , . . . . . . . . . | $$ | . . O X . . . . . . . . . . . . . . . | $$ | . . O . X . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . O X X . . . . . . . . . . . . O . . | $$ | . O O X . . . . . 3 . . . . . X O . . | $$ | . O X O . . . . . . . . . O O O . O . | $$ | . b X X X . . . . 4 . . X . X X O . O | $$ | . . . . . . . . . . . . . . X . X O . | $$ | . . . . . . . . . . . . . . . X . . . | $$ ---------------------------------------[/go]

Some more about

- it seems KataGo looks at this at a local sente. Then the reduction point is

Click Here To Show Diagram Code: [go]$$W Proper move $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . O . O . O . . X . . . O O . . | $$ | . . O O X . . X . . O X X O O X O . . | $$ | . . O X X . X . . O O O X X . X O O . | $$ | . . . . . . . O . O . X . . . X X X . | $$ | . . O . . . . . O X O . . . . . . . . | $$ | . . a . X . . X X X X . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . 1 . . . . . . . . . . . . X . . | $$ | . . . O B . . . . , . . . . . . . . . | $$ | . . O X . . . . . . . . . . . . . . . | $$ | . . O . X . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . O X X . . . . . . . . . . . . O . . | $$ | . O O X . . . . 5 . . 2 . . . X O . . | $$ | . O X O . . . . . . . . . O O O . O . | $$ | . b X X X . . . . . . 3 X . X X O . O | $$ | . . . . . . . . . . . . 4 . X . X O . | $$ | . . . . . . . . . . . . . . . X . . . | $$ ---------------------------------------[/go]

If

as ambitious as here, then

is a forcing move that helps

later I guess

Click Here To Show Diagram Code: [go]$$W Proper move $$ --------------------------------------- $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . . O . O . O . . X . . . O O . . | $$ | . . O O X . . X . . O X X O O X O . . | $$ | . . O X X . X . . O O O X X . X O O . | $$ | . . . . . . . O . O . X . . . X X X . | $$ | . . O . . . . . O X O . . . . . . . . | $$ | . . a . X . . X X X X . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . . . 1 3 . . . . . . . . . . . X . . | $$ | . . . O B . . . . , . . . . . . . . . | $$ | . . O X . . . . . . . . . . . . . . . | $$ | . . O . X . . . . . . . . . . . . . . | $$ | . . . . . . . . . . . . . . . . . . . | $$ | . O X X . . . . . . . . . . . . O . . | $$ | . O O X . . . . . . . . . . . X O . . | $$ | . O X O . . . . . 2 . . . O O O . O . | $$ | . b X X X . . . . . . . X . X X O . O | $$ | . . . . . . . . . . . . . . X . X O . | $$ | . . . . . . . . . . . . . . . X . . . | $$ ---------------------------------------[/go]

If

expands in a more modest fashion, then turning at

seems to be enough

Life In 19x19

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Re: Dieter's ABC of mistakes - 3

Re: Dieter's ABC of mistakes - 3

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