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 Post subject: Re: Kirby's Study Journal
Post #841 Posted: Tue Aug 16, 2016 11:22 pm 
Honinbo

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I played a game today, and tried streaming again. I'm a little bit of a noob at streaming, so I screwed up the first 10 minutes of the video (I wasn't showing the board). So I won't include the video here for now.

I also didn't do a review, yet. I didn't have time after the game, and I had to attend to some medical stuff for my family today - so I'm a bit tired to do a review right now.

But here it is, for your viewing pleasure.


While I didn't review this game, I think I was a bit too casual with how I handled his group on top. Maybe I was thinking too much about the streaming, but I didn't really count liberties or anything, and assumed my group would be fine. It turned into the situation where I was the one running and being attacked.

Luckily for me, he let me break into the side and kill him. So it worked out in terms of game result, even if not in terms of game quality.

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Post #842 Posted: Wed Aug 17, 2016 12:53 am 
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Hi Brian,

Not crazy about :b31: ...

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Post #843 Posted: Wed Aug 17, 2016 9:48 am 
Oza
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EdLee wrote:
Hi Brian,

Not crazy about :b31: ...


Brian is white...

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 Post subject: Re: Kirby's Study Journal
Post #844 Posted: Fri Aug 19, 2016 10:58 pm 
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Haven't reviewed or played any more games yet due to some medical stuff, but I have been doing some go problems now and then, when I get a few minutes.

I ran across one problem that I liked, which I wanted to share:
Click Here To Show Diagram Code
[go]$$B
$$ ---------------------------------------
$$ | . . . . . . . . . . . O O O . X X X . |
$$ | . . . . . . . . . X . O X . O O O O X |
$$ | . . . . . . . . . . X X . . . . O X . |
$$ | . . . , . . . . . , . . X . O O X . O |
$$ | . . . . . . . . . . . . . X X X . X X |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]


I like this problem because:
1.) There aren't that many possible moves, so it shouldn't take long to iterate all possibilities.
2.) I was still stumped by it for awhile :-)

I'll add the reason I was stumped in hide tags, in case anyone is interested in the problem without hints.

Maybe a couple of years ago, I ran across a go blog, which stated that in life and death problems, if you capture any shape consisting of 3-stones, it's enough space to make an eye. I remember being quite interested in this, because I hadn't realized it before. I thought, "Wow, I guess that's right", and couldn't think of an exception.

As a result, when I do life and death problems, my mind stops reading when I see a 3-stone group that will be captured, and I assume that it implies that the opponent will get an eye there. So basically, seeing 3-stones that would be captured was equivalent to an eye in my mind.

However, this problem proves that this heuristic that I've been using is wrong! Indeed, I assumed that the three black stones on top were definitely an eye for white:
Click Here To Show Diagram Code
[go]$$B
$$ ---------------------------------------
$$ | . . . . . . . . . . . O O O . B B B . |
$$ | . . . . . . . . . X . O X . O O O O X |
$$ | . . . . . . . . . . X X . . . a O X . |
$$ | . . . , . . . . . , . . X . O O X . O |
$$ | . . . . . . . . . . . . . X X X . X X |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]


Furthermore, since I could not take away the eye at 'a', and because I couldn't create a shortage of liberties to prevent white from capturing the three black stones... I was at a loss.

So I'm glad I ran into this problem. It showed me that the heuristic that I had been using is incorrect. Also, while I was looking for that blog where I found this, I noticed this SL page, which indeed, indicates that there are exceptions to the rule.


Anyway, that's all I have for this problem. It's a pretty simple problem, which showed a flaw in the basic reasoning I utilize doing go problems.

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Post #845 Posted: Fri Aug 19, 2016 11:29 pm 
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Click Here To Show Diagram Code
[go]$$B
$$--------------------------
$$ . . . . O O O . X X X . |
$$ . . X . O X . O O O O X |
$$ . . . X X . . . . O X . |
$$ . . , . . X . O O X . O |
$$ . . . . . . X X X . X X |
$$ . . . . . . . . . . . . |[/go]
Click Here To Show Diagram Code
[go]$$B
$$--------------------------
$$ . . . . O O O 4 X X X 6 |
$$ . . X . O X . O O O O X |
$$ . . . X X . 1 2 . O X 5 |
$$ . . , . . X . O O X 3 O |
$$ . . . . . . X X X . X X |
$$ . . . . . . . . . . . . |[/go]
Click Here To Show Diagram Code
[go]$$B :w1: :b3: W lives
$$--------------------------
$$ . . . . O O O 4 . 8 7 O |
$$ . . X . O X . O O O O X |
$$ . . . X X . X O . O X X |
$$ . . , . . X . O O X X . |
$$ . . . . . . X X X . X X |
$$ . . . . . . . . . . . . |[/go]
Click Here To Show Diagram Code
[go]$$B
$$--------------------------
$$ . . . . O O O . X X X . |
$$ . . X . O X . O O O O X |
$$ . . . X X . 2 1 4 O X . |
$$ . . , . . X 3 O O X . O |
$$ . . . . . . X X X . X X |
$$ . . . . . . . . . . . . |[/go]
Click Here To Show Diagram Code
[go]$$B :b1: W lives
$$--------------------------
$$ . . . . O O O . X X X . |
$$ . . X . O X 6 O O O O X |
$$ . . . X X 5 O . O O X . |
$$ . . , . . X X O O X . O |
$$ . . . . . . X X X . X X |
$$ . . . . . . . . . . . . |[/go]
Click Here To Show Diagram Code
[go]$$B
$$--------------------------
$$ . . . . O O O 2 X X X 6 |
$$ . . X . O X 1 O O O O X |
$$ . . . X X 5 4 3 . O X . |
$$ . . , . . X . O O X . O |
$$ . . . . . . X X X . X X |
$$ . . . . . . . . . . . . |[/go]
Click Here To Show Diagram Code
[go]$$B :b3:
$$--------------------------
$$ . . . . O O O O . 8 7 O |
$$ . . X . O X X O O O O X |
$$ . . . X X X O X . O X 9 |
$$ . . , . . X . O O X . O |
$$ . . . . . . X X X . X X |
$$ . . . . . . . . . . . . |[/go]
Click Here To Show Diagram Code
[go]$$Wm10 :b3: :w1:
$$--------------------------
$$ . . . . O O O O . O X 1 |
$$ . . X . O X X O O O O X |
$$ . . . X X X O X . O X X |
$$ . . , . . X . O O X 2 O |
$$ . . . . . . X X X . X X |
$$ . . . . . . . . . . . . |[/go]
Click Here To Show Diagram Code
[go]$$B
$$--------------------------
$$ . . . . O O O 3 X X X 4 |
$$ . . X . O X 1 O O O O X |
$$ . . . X X . . 2 . O X . |
$$ . . , . . X . O O X . O |
$$ . . . . . . X X X . X X |
$$ . . . . . . . . . . . . |[/go]
Click Here To Show Diagram Code
[go]$$B :b4:
$$--------------------------
$$ . . . . O O O 7 . 6 5 O |
$$ . . X . O X X O O O O X |
$$ . . . X X . . O . O X . |
$$ . . , . . X . O O X . O |
$$ . . . . . . X X X . X X |
$$ . . . . . . . . . . . . |[/go]
Click Here To Show Diagram Code
[go]$$B :b4: :w1:
$$--------------------------
$$ . . . . O O O X . O X 8 |
$$ . . X . O X X O O O O X |
$$ . . . X X . . O . O X . |
$$ . . , . . X . O O X . O |
$$ . . . . . . X X X . X X |
$$ . . . . . . . . . . . . |[/go]


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 Post subject: Re: Kirby's Study Journal
Post #846 Posted: Sat Aug 20, 2016 12:16 am 
Judan

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Nice problem, but is only ko right?


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 Post subject: Re: Kirby's Study Journal
Post #847 Posted: Sat Aug 20, 2016 12:21 am 
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The answer is ko, yes.

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Post #848 Posted: Sat Aug 20, 2016 7:16 am 
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Kirby wrote:
Haven't reviewed or played any more games yet due to some medical stuff, but I have been doing some go problems now and then, when I get a few minutes.

I ran across one problem that I liked, which I wanted to share:
Click Here To Show Diagram Code
[go]$$B
$$ ---------------------------------------
$$ | . . . . . . . . . . . O O O . X X X . |
$$ | . . . . . . . . . X . O X . O O O O X |
$$ | . . . . . . . . . . X X . . . . O X . |
$$ | . . . , . . . . . , . . X . O O X . O |
$$ | . . . . . . . . . . . . . X X X . X X |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]


Thank you. A very nice problem. :)


Kirby wrote:
Maybe a couple of years ago, I ran across a go blog, which stated that in life and death problems, if you capture any shape consisting of 3-stones, it's enough space to make an eye. I remember being quite interested in this, because I hadn't realized it before. I thought, "Wow, I guess that's right", and couldn't think of an exception.


I'll come back to that below. :)

Quote:
As a result, when I do life and death problems, my mind stops reading when I see a 3-stone group that will be captured, and I assume that it implies that the opponent will get an eye there. So basically, seeing 3-stones that would be captured was equivalent to an eye in my mind.

However, this problem proves that this heuristic that I've been using is wrong! Indeed, I assumed that the three black stones on top were definitely an eye for white:
Click Here To Show Diagram Code
[go]$$B
$$ ---------------------------------------
$$ | . . . . . . . . . . . O O W b B B B . |
$$ | . . . . . . . . . X . O X . W O O O X |
$$ | . . . . . . . . . . X X . . . a O X . |
$$ | . . . , . . . . . , . . X . O O X . O |
$$ | . . . . . . . . . . . . . X X X . X X |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]


Furthermore, since I could not take away the eye at 'a', and because I couldn't create a shortage of liberties to prevent white from capturing the three black stones... I was at a loss.
(White markings and "b" added by me.)

Wow! That's three heuristics violated by this problem. :)

1) Capturing a three stone string produces an eye.
2) White has an eye at "a".
3) The :wc: stones are connected.

Oops! Sorry. The first heuristic is not violated. If White captures the marked three stone string White indeed has an eye there. What is violated is this heuristic:

Capturing a four stone string produces an eye. :lol:

If White captures only the three marked stones he has an eye there. So that heuristic is not violated. :)

BTW, I never learned that capture three heuristic. I figured out something better for myself, which says that in this position if White plays at "b" he can capture the three :bc: stones for an eye.

I never learned the heuristic about White having an eye at "a", because it is simply false. ;)

And everybody knows that the diagonal connection can sometimes be cut. :)

Now to return to the theme of thinking of an exception to the capture three heuristic. It is no secret that I do not belong to the reading über alles persuasion. ;) I think that both knowledge and heuristics are important. (And, OC, knowledge trumps heuristics. :)) Now, thinking of an exception to a heuristic is not a reading problem per se; it is more difficult, as you have to imagine a position and then read it out. There is no shame in not thinking of an exception. IMO, when you are learning, thinking is not enough. Do what children do and play with stones on the board. :) Let's play around a bit.

Remember that bit of go knowledge that eight stones in a row on the second line are alive?

Click Here To Show Diagram Code
[go]$$B Eight lives
$$ ------------------------------
$$ . . . . 1 2 C C C C 4 3 . . . .
$$ . X . X O O O O O O O O X . X .
$$ . . . X X X X X X X X X X . . .
$$ . . . . . . . . . . . . . . . .[/go]


Even when Black plays first, White has a four point linear eye, which is enough to live.

Click Here To Show Diagram Code
[go]$$B Eight lives, variation
$$ ------------------------------
$$ . . . . 1 3 4 C C C C 2 . . . .
$$ . X . X O O O O O O O O X . X .
$$ . . . X X X X X X X X X X . . .
$$ . . . . . . . . . . . . . . . .[/go]



Click Here To Show Diagram Code
[go]$$B Eight lives with hanes
$$ ------------------------------
$$ . . . O 1 3 . . . . . 2 O . . .
$$ . X . X O O O O O O O O X . X .
$$ . . . X X X X X X X X X X . . .
$$ . . . . . . . . . . . . . . . .[/go]


Hmmm. With the hanes White does not have to answer :b3:. I have learned something today by playing around. :D

Click Here To Show Diagram Code
[go]$$B Eight lives with hanes, continued
$$ ------------------------------
$$ . . . O B X 2 . 4 1 . O O . . .
$$ . X . X O O O O O O O O X . X .
$$ . . . X X X X X X X X X X . . .
$$ . . . . . . . . . . . . . . . .[/go]

:b3: throws in at :bc:

:b1: does not work, since capturing the two stones gives White a half eye. With one and a half eyes in the four point eye, White is alive. :) If :b3: at 4, :w4: at :bc:, OC.

Does that mean that seven lives with hanes? Let's play around and see. :)

Click Here To Show Diagram Code
[go]$$B Does seven live with hanes?
$$ ------------------------------
$$ . . . O 1 a . . 3 . 2 O . . .
$$ . X . X O O O O O O O X . X .
$$ . . . X X X X X X X X X . . .
$$ . . . . . . . . . . . . . . .[/go]


Nope. :b3: kills. :b3: at "a" would be a mistake, OC.

Isn't go fun? :D

Back to eight lives.

Click Here To Show Diagram Code
[go]$$W Capture eight and live
$$ ------------------------------
$$ . . . 1 X X X X X X X X O . . .
$$ . X . X O O O O O O O O X . X .
$$ . . . X X X X . X X X X X . . .
$$ . . . . . . . . . . . . . . . .[/go]


Playing around a bit, we find that capturing eight stones lives. And it lives by making a four point eye. (We have just seen that capturing seven does not live.)

Well, 8 - 4 = 4. Does that mean that capturing five stones makes a one point eye? 'Deed it does. :)

Click Here To Show Diagram Code
[go]$$W Capture 5 for an eye
$$ ------------------------
$$ . . . 1 X X X X X O . . .
$$ . X . X O O O O O X . X .
$$ . . . X O . O X X X . . .
$$ . . . X X O O X . . . . .
$$ . . . . . X X X . . . . .
$$ . . . . . . . . . . . . .[/go]


Click Here To Show Diagram Code
[go]$$W Capture 5 for an eye, continued
$$ ------------------------
$$ . . . O 2 3 . 5 4 O . . .
$$ . X . X O O O O O X . X .
$$ . . . X O . O X X X . . .
$$ . . . X X O O X . . . . .
$$ . . . . . X X X . . . . .
$$ . . . . . . . . . . . . .[/go]


Click Here To Show Diagram Code
[go]$$W Capture 5 for an eye, variation
$$ ------------------------
$$ . . . O 2 4 . . 3 O . . .
$$ . X . X O O O O O X . X .
$$ . . . X O . O X X X . . .
$$ . . . X X O O X . . . . .
$$ . . . . . X X X . . . . .
$$ . . . . . . . . . . . . .[/go]


White can ignore :b4:. :)

Well, if you have to capture five in a row to make an eye, where did the capture three heuristic come from?

Click Here To Show Diagram Code
[go]$$W Capture 3 for an eye
$$ ------------------------
$$ . . . 1 X X X O . . . .
$$ . X . X O O O W X . X .
$$ . . . X O . O X X . . .
$$ . . . X X O O X . . . .
$$ . . . . . X X X . . . .
$$ . . . . . . . . . . . .[/go]


The heuristic came from ignoring the go knowledge that the corner of the eye has to be occupied or controlled, as indicated by the :wc: stone. Away from the edge there are other corners to consider, as the SL page ( http://senseis.xmp.net/?CaptureThreeToMakeAnEye ) discusses.

BTW, I am annoyed at the SL page, which talks about the heuristic as a proverb and mentions exceptions to it. The correct go knowledge is no more esoteric than the knowledge that eight in a row on the second line lives. Knowledge trumps heuristics. :)

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Everything with love. Stay safe.


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 Post subject: Re: Kirby's Study Journal
Post #849 Posted: Sat Aug 20, 2016 11:14 pm 
Honinbo

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At the hospital right now, so I haven't done much studying. Also haven't reviewed much. But I decided to try to level up my Tygem account, which is currently 3d. I think 1d on KGS can be at least 4d on Tygem, so the games were not that bad.

I played three games and won them all by a good margin, against the same opponent. He challenged me again for a 4th game, but I got too tired and stopped.

In the game where I only won by 18.5, I was careless and got cut off in the center - so he killed it all there. Luckily, I killed the left side, so it was all good.

Here are the games.






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Post #850 Posted: Sat Aug 20, 2016 11:15 pm 
Honinbo

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Bill Spight wrote:
Kirby wrote:
Haven't reviewed or played any more games yet due to some medical stuff, but I have been doing some go problems now and then, when I get a few minutes.

I ran across one problem that I liked, which I wanted to share:
Click Here To Show Diagram Code
[go]$$B
$$ ---------------------------------------
$$ | . . . . . . . . . . . O O O . X X X . |
$$ | . . . . . . . . . X . O X . O O O O X |
$$ | . . . . . . . . . . X X . . . . O X . |
$$ | . . . , . . . . . , . . X . O O X . O |
$$ | . . . . . . . . . . . . . X X X . X X |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]


Thank you. A very nice problem. :)


Kirby wrote:
Maybe a couple of years ago, I ran across a go blog, which stated that in life and death problems, if you capture any shape consisting of 3-stones, it's enough space to make an eye. I remember being quite interested in this, because I hadn't realized it before. I thought, "Wow, I guess that's right", and couldn't think of an exception.


I'll come back to that below. :)

Quote:
As a result, when I do life and death problems, my mind stops reading when I see a 3-stone group that will be captured, and I assume that it implies that the opponent will get an eye there. So basically, seeing 3-stones that would be captured was equivalent to an eye in my mind.

However, this problem proves that this heuristic that I've been using is wrong! Indeed, I assumed that the three black stones on top were definitely an eye for white:
Click Here To Show Diagram Code
[go]$$B
$$ ---------------------------------------
$$ | . . . . . . . . . . . O O W b B B B . |
$$ | . . . . . . . . . X . O X . W O O O X |
$$ | . . . . . . . . . . X X . . . a O X . |
$$ | . . . , . . . . . , . . X . O O X . O |
$$ | . . . . . . . . . . . . . X X X . X X |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]


Furthermore, since I could not take away the eye at 'a', and because I couldn't create a shortage of liberties to prevent white from capturing the three black stones... I was at a loss.
(White markings and "b" added by me.)

Wow! That's three heuristics violated by this problem. :)

1) Capturing a three stone string produces an eye.
2) White has an eye at "a".
3) The :wc: stones are connected.

Oops! Sorry. The first heuristic is not violated. If White captures the marked three stone string White indeed has an eye there. What is violated is this heuristic:

Capturing a four stone string produces an eye. :lol:

If White captures only the three marked stones he has an eye there. So that heuristic is not violated. :)

BTW, I never learned that capture three heuristic. I figured out something better for myself, which says that in this position if White plays at "b" he can capture the three :bc: stones for an eye.

I never learned the heuristic about White having an eye at "a", because it is simply false. ;)

And everybody knows that the diagonal connection can sometimes be cut. :)

Now to return to the theme of thinking of an exception to the capture three heuristic. It is no secret that I do not belong to the reading über alles persuasion. ;) I think that both knowledge and heuristics are important. (And, OC, knowledge trumps heuristics. :)) Now, thinking of an exception to a heuristic is not a reading problem per se; it is more difficult, as you have to imagine a position and then read it out. There is no shame in not thinking of an exception. IMO, when you are learning, thinking is not enough. Do what children do and play with stones on the board. :) Let's play around a bit.

Remember that bit of go knowledge that eight stones in a row on the second line are alive?

Click Here To Show Diagram Code
[go]$$B Eight lives
$$ ------------------------------
$$ . . . . 1 2 C C C C 4 3 . . . .
$$ . X . X O O O O O O O O X . X .
$$ . . . X X X X X X X X X X . . .
$$ . . . . . . . . . . . . . . . .[/go]


Even when Black plays first, White has a four point linear eye, which is enough to live.

Click Here To Show Diagram Code
[go]$$B Eight lives, variation
$$ ------------------------------
$$ . . . . 1 3 4 C C C C 2 . . . .
$$ . X . X O O O O O O O O X . X .
$$ . . . X X X X X X X X X X . . .
$$ . . . . . . . . . . . . . . . .[/go]



Click Here To Show Diagram Code
[go]$$B Eight lives with hanes
$$ ------------------------------
$$ . . . O 1 3 . . . . . 2 O . . .
$$ . X . X O O O O O O O O X . X .
$$ . . . X X X X X X X X X X . . .
$$ . . . . . . . . . . . . . . . .[/go]


Hmmm. With the hanes White does not have to answer :b3:. I have learned something today by playing around. :D

Click Here To Show Diagram Code
[go]$$B Eight lives with hanes, continued
$$ ------------------------------
$$ . . . O B X 2 . 4 1 . O O . . .
$$ . X . X O O O O O O O O X . X .
$$ . . . X X X X X X X X X X . . .
$$ . . . . . . . . . . . . . . . .[/go]

:b3: throws in at :bc:

:b1: does not work, since capturing the two stones gives White a half eye. With one and a half eyes in the four point eye, White is alive. :) If :b3: at 4, :w4: at :bc:, OC.

Does that mean that seven lives with hanes? Let's play around and see. :)

Click Here To Show Diagram Code
[go]$$B Does seven live with hanes?
$$ ------------------------------
$$ . . . O 1 a . . 3 . 2 O . . .
$$ . X . X O O O O O O O X . X .
$$ . . . X X X X X X X X X . . .
$$ . . . . . . . . . . . . . . .[/go]


Nope. :b3: kills. :b3: at "a" would be a mistake, OC.

Isn't go fun? :D

Back to eight lives.

Click Here To Show Diagram Code
[go]$$W Capture eight and live
$$ ------------------------------
$$ . . . 1 X X X X X X X X O . . .
$$ . X . X O O O O O O O O X . X .
$$ . . . X X X X . X X X X X . . .
$$ . . . . . . . . . . . . . . . .[/go]


Playing around a bit, we find that capturing eight stones lives. And it lives by making a four point eye. (We have just seen that capturing seven does not live.)

Well, 8 - 4 = 4. Does that mean that capturing five stones makes a one point eye? 'Deed it does. :)

Click Here To Show Diagram Code
[go]$$W Capture 5 for an eye
$$ ------------------------
$$ . . . 1 X X X X X O . . .
$$ . X . X O O O O O X . X .
$$ . . . X O . O X X X . . .
$$ . . . X X O O X . . . . .
$$ . . . . . X X X . . . . .
$$ . . . . . . . . . . . . .[/go]


Click Here To Show Diagram Code
[go]$$W Capture 5 for an eye, continued
$$ ------------------------
$$ . . . O 2 3 . 5 4 O . . .
$$ . X . X O O O O O X . X .
$$ . . . X O . O X X X . . .
$$ . . . X X O O X . . . . .
$$ . . . . . X X X . . . . .
$$ . . . . . . . . . . . . .[/go]


Click Here To Show Diagram Code
[go]$$W Capture 5 for an eye, variation
$$ ------------------------
$$ . . . O 2 4 . . 3 O . . .
$$ . X . X O O O O O X . X .
$$ . . . X O . O X X X . . .
$$ . . . X X O O X . . . . .
$$ . . . . . X X X . . . . .
$$ . . . . . . . . . . . . .[/go]


White can ignore :b4:. :)

Well, if you have to capture five in a row to make an eye, where did the capture three heuristic come from?

Click Here To Show Diagram Code
[go]$$W Capture 3 for an eye
$$ ------------------------
$$ . . . 1 X X X O . . . .
$$ . X . X O O O W X . X .
$$ . . . X O . O X X . . .
$$ . . . X X O O X . . . .
$$ . . . . . X X X . . . .
$$ . . . . . . . . . . . .[/go]


The heuristic came from ignoring the go knowledge that the corner of the eye has to be occupied or controlled, as indicated by the :wc: stone. Away from the edge there are other corners to consider, as the SL page ( http://senseis.xmp.net/?CaptureThreeToMakeAnEye ) discusses.

BTW, I am annoyed at the SL page, which talks about the heuristic as a proverb and mentions exceptions to it. The correct go knowledge is no more esoteric than the knowledge that eight in a row on the second line lives. Knowledge trumps heuristics. :)


Bill, I was a bit imprecise in my description - thanks for clarifying. Also, nice examples.

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 Post subject: Re: Kirby's Study Journal
Post #851 Posted: Sun Aug 21, 2016 2:40 am 
Oza
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Here's a problem that is a good deal easier than the one you posted, but it stumped me at first for a similar reason: “It ain’t what you don’t know that gets you into trouble. It’s what you know for sure that just ain’t so.” -Mark Twain

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


This wasn't a dead shape in my book...

Click Here To Show Diagram Code
[go]$$B
$$ +-------------------+
$$ | . . . . . . . . . |
$$ | . . . . . . . . . |
$$ | . . . . X . . . . |
$$ | . . X X X X . . . |
$$ | . . . . . . . . . |
$$ | . . . . . . . . . |
$$ +-------------------+[/go]

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This post by daal was liked by 3 people: Bill Spight, EdLee, Kirby
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Post #852 Posted: Sun Aug 21, 2016 8:46 am 
Honinbo

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In general, an interesting thing about go is how the "rules" change. As I've gained experience, I've learned rules that have helped guide play - even with more global shapes like josekis, etc.: "This is good for black, this would be good for white. If it's a shape like this, black will get territory in this area."

But depending on the nuances of the situation (weak groups, moves the opponent must respond to, etc.), these "rules" change. Maybe on an empty board, that wide extension wouldn't be territory. But because of the nearby stones, it's going to be territory, etc.

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Post #853 Posted: Sun Aug 21, 2016 9:44 am 
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Click Here To Show Diagram Code
[go]$$B
$$ | ...........
$$ | ......X....
$$ | XXXXX..XX,.
$$ | XOOOOOOOX..
$$ | OOOXOXXX...
$$ | ..XXXO.....
$$ +------------[/go]
Click Here To Show Diagram Code
[go]$$B
$$ | ...........
$$ | ......X....
$$ | XXXXX..XX,.
$$ | XOOOOOOOX..
$$ | OOOXOXXX...
$$ | 21XXXO.....
$$ +------------[/go]
Click Here To Show Diagram Code
[go]$$B :b4: (a),(b) miai
$$ | ...........
$$ | ......X....
$$ | XXXXX..XX,.
$$ | XOOOOOOOX..
$$ | OOO.OXXX...
$$ | O.a3bO.....
$$ +------------[/go]
Click Here To Show Diagram Code
[go]$$W
$$ | ...........
$$ | ......X....
$$ | XXXXX..XX..
$$ | XOOOOOOOX,.
$$ | OOOXOXXX...
$$ | .1XXXO.....
$$ +------------[/go]
Instant life for W, so if :b1: at :w1: doesn't kill, then probably hopeless. :)

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Post #854 Posted: Sun Aug 21, 2016 11:17 am 
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EdLee wrote:
Click Here To Show Diagram Code
[go]$$B
$$ | ...........
$$ | ......X....
$$ | XXXXX..XX..
$$ | XOOOOOOOX..
$$ | OOOXOXXX...
$$ | ..XXXO.....
$$ +------------[/go]
Click Here To Show Diagram Code
[go]$$B
$$ | ...........
$$ | ......X....
$$ | XXXXX..XX..
$$ | XOOOOOOOX..
$$ | OOOXOXXX...
$$ | 21XXXO.....
$$ +------------[/go]
Click Here To Show Diagram Code
[go]$$B :b4: (a),(b) miai
$$ | ...........
$$ | ......X....
$$ | XXXXX..XX..
$$ | XOOOOOOOX..
$$ | OOO.OXXX...
$$ | O.a3bO.....
$$ +------------[/go]
Click Here To Show Diagram Code
[go]$$W
$$ | ...........
$$ | ......X....
$$ | XXXXX..XX..
$$ | XOOOOOOOX..
$$ | OOOXOXXX...
$$ | .1XXXO.....
$$ +------------[/go]
Instant life for W, so if :b1: at :w1: doesn't kill, then probably hopeless. :)


Click Here To Show Diagram Code
[go]$$B 1.5 eyes
$$ | ...........
$$ | ......X....
$$ | XXXXX..XX..
$$ | XOOOOOOOX..
$$ | OOO.OXXX...
$$ | O....O.....
$$ +------------[/go]


Click Here To Show Diagram Code
[go]$$B 1.5 eyes
$$ | ...........
$$ | ......X....
$$ | XXXXX..XX..
$$ | XOOOOOOOX..
$$ | OOOOOOXXX..
$$ | O.....O....
$$ +------------[/go]

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Post #855 Posted: Sun Aug 21, 2016 12:24 pm 
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Hi Bill,
Quote:
1.5 eyes
Back to the basics question: 0.5 eyes means it's possible to get a real eye there with 2 moves ?

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Post #856 Posted: Sun Aug 21, 2016 4:53 pm 
Oza
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EdLee wrote:
Hi Bill,
Quote:
1.5 eyes
Back to the basics question: 0.5 eyes means it's possible to get a real eye there with 2 moves ?

In Japanese 半眼 (half eye) means you have a shape where you can complete an eye with one more move, i.e. in gote. If you can force another eye in sente, you can come back and live by completing your gote eye. I think Bill's 0.5 means the same thing. His 1.5 shape is one move away from completing 2 eyes.

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Post #857 Posted: Sun Aug 21, 2016 7:10 pm 
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EdLee wrote:
Hi Bill,
Quote:
1.5 eyes
Back to the basics question: 0.5 eyes means it's possible to get a real eye there with 2 moves ?


1.5 eyes: White can make 2 eyes in gote; Black can hold White to 1 eye in gote.

1.5 eyes + 0.5 eyes = 2 eyes

Example:

Click Here To Show Diagram Code
[go]$$B Black mistake
$$ ------------------------------
$$ . . . O 1 3 4 . . . 2 O . . .
$$ . X . X O O O O O O O X . X .
$$ . . . X X X X X X X X X . . .
$$ . . . . . . . . . . . . . . .[/go]


:b3: is a mistake, because after :w4: White has 2 eyes.

Click Here To Show Diagram Code
[go]$$B 2 eyes
$$ ------------------------------
$$ . . . O . a O . b . O O . . .
$$ . X . X O O O O O O O X . X .
$$ . . . X X X X X X X X X . . .
$$ . . . . . . . . . . . . . . .[/go]


White has 0.5 eyes at "a" plus 1.5 eyes at "b". :)

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Everything with love. Stay safe.


This post by Bill Spight was liked by: EdLee
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Post #858 Posted: Sun Aug 21, 2016 9:24 pm 
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Thanks, Dave, Bill.

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 Post subject: Re: Kirby's Study Journal
Post #859 Posted: Mon Aug 22, 2016 9:56 pm 
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Still not at home, yet. So I played two more games on Tygem once my son went to bed. I don't plan to review them. They weren't as one sided as the other day, but still lower level than KGS 1d, I think.

Maybe I will start reviewing once I get to Tygem 4d. It says 3 wins to get to 4d, and 7 wins to jump up two and get to 5d:
Image

Here are the games.




First guy was a little rude. The game was over, so I requested to count, and he refused in order to make me wait until his time ran out (something like 6 or 7 minutes left, plus the byo-yomi).

I noticed there is a new feature, at least on the Korean client, which allows you to indicate whether your opponent had good manners and you enjoyed playing against him. I like the idea, though, it seems to make the system a bit more complicated.

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Post #860 Posted: Mon Aug 22, 2016 10:06 pm 
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To elaborate on the manner system that they seem to have added, here is a screenshot:

Image

Basically, after the game, there's a dialog with the option to indicate that your opponent had good manners. If you have less than 30, you have the default icon by your name. At 30, you get the one with a "1", at 50 you get the one with a "2", etc., until you have over 700. At that point, you are a "Manner King" (with icon rainbow-colored and stamped with a "K").

It's an interesting idea, but:
1.) I haven't even played 30 games since they've introduced this feature.
2.) I'd rather identify people having bad manners than people having good manners - good manners should be the default behavior.
3.) Manner King? Seriously?

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