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115 - robinz v. 1986

https://lifein19x19.com/viewtopic.php?t=3740

Page 25 of 31

Re: 115 - robinz v. 1986

Posted: Fri Jul 08, 2011 10:49 am
by robinz
Click Here To Show Diagram Code
[go]$$Bcm195 :w28: :b8:
$$ +---------------------------------------+
$$ | . . . . . . . X . X . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . X O . . O . . X X X |
$$ | . . O . O . . . . O . O O . O X . . X |
$$ | . . O X . . . . . . . . . . . X X X . |
$$ | . O X O O O O . . . . . . . X . X . X |
$$ | . O X X . X X X . . . . . X . X . . . |
$$ | . . X , X . . . . , O . X X X X X . X |
$$ | . . X X X . . . . . . . X . . . X . X |
$$ | . 1 . O . . . . . . . O O X X . . . . |
$$ | . . O . X X X X . X . . . O X . X . . |
$$ | . O O . X O O X O . . . . O X X X X . |
$$ | X X O X . . . O X X . . O . O X . X . |
$$ | . . X O O O . . O , . . . O O X O X X |
$$ | X X X O X O . . . . O . . O . O X X . |
$$ | X O O X X O . . . . . . . . . O X O X |
$$ | . . . O . . . . . . . . . . . O O O O |
$$ +---------------------------------------+[/go]


OK, a day later - and I still think this works. Let's see if he has anything planned.

Basically, this move prevents an eye for him in the ensuing capturing race. Since I have an eye and he doesn't, I get to count any shared liberties - which here is just A6 - as liberties for me but not for him. In that case, he has just 4 liberties, while I have A6, 2 inside the eye, A1, and also the two necessary approach moves before A1 becomes possible: B1 and E1. So I have 6 effective liberties to his 4, which indicates I should win this even if I tenuki on the next move. I'm not quite sure if I believe that, so will need to read carefully next time - but it surely gives justifiable grounds for optimism :D

Re: 115 - robinz v. 1986

Posted: Fri Jul 08, 2011 6:23 pm
by ez4u
Obs:
robinz wrote:[hide]OK, a day later - and I still think this works. Let's see if he has anything planned.

Basically, this move prevents an eye for him in the ensuing capturing race. Since I have an eye and he doesn't, I get to count any shared liberties - which here is just A6 - as liberties for me but not for him. In that case, he has just 4 liberties, while I have A6, 2 inside the eye, A1, and also the two necessary approach moves before A1 becomes possible: B1 and E1. So I have 6 effective liberties to his 4, which indicates I should win this even if I tenuki on the next move. I'm not quite sure if I believe that, so will need to read carefully next time - but it surely gives justifiable grounds for optimism :D


We have to look carefully but the situation is perhaps more straightforward than it seems.
Click Here To Show Diagram Code
[go]$$Bcm195 :w28: :b8:
$$ +---------------------------------------+
$$ | . . . . . . . X . X . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . X O . . O . . X X X |
$$ | . . O . O . . . . O . O O . O X . . X |
$$ | . . O X . . . . . . . . . . . X X X . |
$$ | . O X O O O O . . . . . . . X . X . X |
$$ | . O X X . X X X . . . . . X . X . . . |
$$ | . . X , X . . . . , O . X X X X X . X |
$$ | . . X X X . . . . . . . X . . . X . X |
$$ | . B M O . . . . . . . O O X X . . . . |
$$ | . M O M X X X X . X . . . O X . X . . |
$$ | T O O M X O O X O . . . . O X X X X . |
$$ | X X O X . . . O X X . . O . O X . X . |
$$ | C X X O O O . . O , . . . O O X O X X |
$$ | X X X O X O . . . . O . . O . O X X . |
$$ | X O O X X O . . . . . . . . . O X O X |
$$ | C C . O C . . . . . . . . . . O O O O |
$$ +---------------------------------------+[/go]

Remember that White will always throw in during any fight and reduce the Black eye to a single point. Black therefore has five liberties, the four points marked with circles and the shared point marked with a triangle. Meanwhile White has five liberties as well, the four points marked "x" and the triangle point. As long as Black filled a White liberty, he would win. The marked stone ( :b95: ) did not fill a liberty. If White now plays at the triangle point, he will reduce Black to four liberties while retaining five himself. White is now in a position to win the fight without needing to play the ko.

Robinz has misunderstood the meaning of a shared liberty in a fight. The triangle point is on the external border of the groups. It will be filled first rather than last. In the situation below both sides have five liberties but White can not win (as long as Black does not fill the triangle point himself). The triangle point is a shared, internal liberty. If White plays at the triangle point, he reduces his own liberties as well as Black's. The game situation is fundamentally different.
Click Here To Show Diagram Code
[go]$$Bcm195 :w28: :b8:
$$ +---------------------------------------+
$$ | . . . . . . . X . X . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . X O . . O . . X X X |
$$ | . . O . O . . . . O . O O . O X . . X |
$$ | . . O X . . . . . . . . . . . X X X . |
$$ | . O X O O O O . . . . . . . X . X . X |
$$ | . O X X . X X X . . . . . X . X . . . |
$$ | . . X , X . . . . , O . X X X X X . X |
$$ | X . X X X . . . . . . . X . . . X . X |
$$ | M B M O . . . . . . . O O X X . . . . |
$$ | O O O M X X X X . X . . . O X . X . . |
$$ | T O O M X O O X O . . . . O X X X X . |
$$ | X X O X . . . O X X . . O . O X . X . |
$$ | C X X O O O . . O , . . . O O X O X X |
$$ | X X X O X O . . . . O . . O . O X X . |
$$ | X O O X X O . . . . . . . . . O X O X |
$$ | C C . O C . . . . . . . . . . O O O O |
$$ +---------------------------------------+[/go]

Re: 115 - robinz v. 1986

Posted: Sat Jul 09, 2011 8:12 pm
by 1986
Click Here To Show Diagram Code
[go]$$Wcm196 Prisoner Count :w28: :b8:
$$ +---------------------------------------+
$$ | . . . . . . . X . X . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . X O . . O . . X X X |
$$ | . . O . O . . . . O . O O . O X . . X |
$$ | . . O X . . . . . . . . . . . X X X . |
$$ | . O X O O O O . . . . . . . X . X . X |
$$ | . O X X . X X X . . . . . X . X . . . |
$$ | . . X , X . . . . , O . X X X X X . X |
$$ | . . X X X . . . . . . . X . . . X . X |
$$ | . X . O . . . . . . . O O X X . . . . |
$$ | . . O . X X X X . X . . . O X . X . . |
$$ | 1 O O . X O O X O . . . . O X X X X . |
$$ | X X O X . . . O X X . . O . O X . X . |
$$ | . . X O O O . . O , . . . O O X O X X |
$$ | X X X O X O . . . . O . . O . O X X . |
$$ | X O O X X O . . . . . . . . . O X O X |
$$ | . . . O . . . . . . . . . . . O O O O |
$$ +---------------------------------------+[/go]


interesting im thinking he is playing in the wrong direction because why would he play there e18 looks much better, if he tries a capturing race, with the a6 stones i win by one liberty, oh well its sente maybe he is just setting me up for a play on the upper side

Re: 115 - robinz v. 1986

Posted: Sun Jul 10, 2011 4:17 am
by robinz
Click Here To Show Diagram Code
[go]$$Bcm197 Prisoner Count :w28: :b8:
$$ +---------------------------------------+
$$ | . . . . . . . X . X . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . X O . . O . . X X X |
$$ | . . O . O . . . . O . O O . O X . . X |
$$ | . . O X . . . . . . . . . . . X X X . |
$$ | . O X O O O O . . . . . . . X . X . X |
$$ | . O X X . X X X . . . . . X . X . . . |
$$ | . . X , X . . . . , O . X X X X X . X |
$$ | . . X X X . . . . . . . X . . . X . X |
$$ | . X . O . . . . . . . O O X X . . . . |
$$ | . . O . X X X X . X . . . O X . X . . |
$$ | O O O . X O O X O . . . . O X X X X . |
$$ | X X O X . . . O X X . . O . O X . X . |
$$ | . . X O O O . . O , . . . O O X O X X |
$$ | X X X O X O . . . . O . . O . O X X . |
$$ | X O O X X O . . . . . . . . . O X O X |
$$ | . 1 . O . . . . . . . . . . . O O O O |
$$ +---------------------------------------+[/go]


OK, that clarifies things - but unfortunately what it reveals isn't good at all :sad: At first I thought it was 5 liberties each (counting the approach moves necessary for white), but that was before I realised that A4 or B4 for white was atari on my 2 stones. If I respond to it, white gains sente and wins the race, while if I don't, I lose the two stones and, shortly afterwards, the whole group.

So I'm having to change tack - playing this move first in sente means that I at least get a ko, so some compensation for my group dying. Unfortunately, it's a 3-step ko for me, so it's inconceivable that I can win it. I do have a few ko threats, but even following up on those (bearing in mind that white can quite happily ignore the first couple) is going to leave me about 20 points behind, which is probably too much for this stage of the game. But I'll see what comes out of this and then do a careful count - there's no point throwing in the towel just yet.

Re: 115 - robinz v. 1986

Posted: Sun Jul 10, 2011 11:44 am
by 1986
Click Here To Show Diagram Code
[go]$$Wcm198 Prisoner Count :w28: :b11:
$$ +---------------------------------------+
$$ | . . . . . . . X . X . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . X O . . O . . X X X |
$$ | . . O . O . . . . O . O O . O X . . X |
$$ | . . O X . . . . . . . . . . . X X X . |
$$ | . O X O O O O . . . . . . . X . X . X |
$$ | . O X X . X X X . . . . . X . X . . . |
$$ | . . X , X . . . . , O . X X X X X . X |
$$ | . . X X X . . . . . . . X . . . X . X |
$$ | . X . O . . . . . . . O O X X . . . . |
$$ | . . O . X X X X . X . . . O X . X . . |
$$ | O O O . X O O X O . . . . O X X X X . |
$$ | X X O X . . . O X X . . O . O X . X . |
$$ | . . X O O O . . O , . . . O O X O X X |
$$ | X X X O . O . . . . O . . O . O X X . |
$$ | X O O . . O . . . . . . . . . O X O X |
$$ | . X . O 1 . . . . . . . . . . O O O O |
$$ +---------------------------------------+[/go]


i dont know why he is playing here, i still have one more liberty if he tries to capture my a6 stones, but its still his sente and he still has better moves on the board so i just have to wait for the chance to take the initiative

Re: 115 - robinz v. 1986

Posted: Sun Jul 10, 2011 2:01 pm
by robinz
Click Here To Show Diagram Code
[go]$$Bcm199 Prisoner Count :w28: :b11:
$$ +---------------------------------------+
$$ | . . . . . . . X . X . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . X O . . O . . X X X |
$$ | . . O . O . . . . O . O O . O X . . X |
$$ | . . O X . . . . . . . . . . . X X X . |
$$ | . O X O O O O . . . . . . . X . X . X |
$$ | . O X X . X X X . . . . . X . X . . . |
$$ | . . X , X . . . . , O . X X X X X . X |
$$ | . . X X X . . . . . . . X . . . X . X |
$$ | . X . O . . . . . . . O O X X . . . . |
$$ | 1 . O . X X X X . X . . . O X . X . . |
$$ | O O O . X O O X O . . . . O X X X X . |
$$ | X X O X . . . O X X . . O . O X . X . |
$$ | . . X O O O . . O , . . . O O X O X X |
$$ | X X X O . O . . . . O . . O . O X X . |
$$ | X O O . . O . . . . . . . . . O X O X |
$$ | . X . O O . . . . . . . . . . O O O O |
$$ +---------------------------------------+[/go]


So here goes the final push - towards a ko I surely can't gain anything much out of, but where I'll have a <insert expletive of choice> good try ;-)

Posted: Thu Jul 14, 2011 4:22 pm
by EdLee
robinz, 1986:
These are now unhidden, after :black:191: Posts 244, 251, 262, 263, 269, 271, 279, 306. :)

Re: 115 - robinz v. 1986

Posted: Fri Jul 15, 2011 2:20 pm
by 1986
i apologize for the inconvience
i had a busy work week
next week i will be busy too but by firday i will be back online, i will just get a laptop so sorry for the wait without notice

Click Here To Show Diagram Code
[go]$$Wcm200 Prisoner Count :w28: :b11:
$$ +---------------------------------------+
$$ | . . . . . . . X . X . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . X O . . O . . X X X |
$$ | . . O . O . . . . O . O O . O X . . X |
$$ | . . O X . . . . . . . . . . . X X X . |
$$ | . O X O O O O . . . . . . . X . X . X |
$$ | . O X X . X X X . . . . . X . X . . . |
$$ | . . X , X . . . . , O . X X X X X . X |
$$ | . . X X X . . . . . . . X . . . X . X |
$$ | . X . O . . . . . . . O O X X . . . . |
$$ | X . O . X X X X . X . . . O X . X . . |
$$ | O O O . X O O X O . . . . O X X X X . |
$$ | X X O X . . . O X X . . O . O X . X . |
$$ | . 1 X O O O . . O , . . . O O X O X X |
$$ | X X X O . O . . . . O . . O . O X X . |
$$ | X O O . . O . . . . . . . . . O X O X |
$$ | . X . O O . . . . . . . . . . O O O O |
$$ +---------------------------------------+[/go]



im still waiting for him to play a different area of the board like e18 im sure this capturing race dosen't work out for him, its still about even on the score, so lets get it on

Re: 115 - robinz v. 1986

Posted: Fri Jul 15, 2011 2:57 pm
by robinz
No problem with the delay :)

@EdLee: thanks for unhiding those comments; what you say makes sense, although I will save a lengthy postmortem for when the game is actually over. (At the point that I made the offending move, I still believed I had things 100% in control - what was fatal for me was somehow missing the potential for a ko on the bottom, which made me change my planned sequence when I spotted it.)

As an aside, I doubt that many Malkovich games have reached 200, and certainly not with still so much fighting going on rather than small endgame moves :lol:

Click Here To Show Diagram Code
[go]$$Bcm201 Prisoner Count :w29: :b11:
$$ +---------------------------------------+
$$ | . . . . . . . X . X . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . X O . . O . . X X X |
$$ | . . O . O . . . . O . O O . O X . . X |
$$ | . . O X . . . . . . . . . . . X X X . |
$$ | . O X O O O O . . . . . . . X . X . X |
$$ | . O X X . X X X . . . . . X . X . . . |
$$ | . . X , X . . . . , O . X X X X X . X |
$$ | . . X X X . . . . . . . X . . . X . X |
$$ | . X . O . . . . . . . O O X X . . . . |
$$ | X . O . X X X X . X . . . O X . X . . |
$$ | O O O . X O O X O . . . . O X X X X . |
$$ | X X O X . . . O X X . . O . O X . X . |
$$ | 1 . X O O O . . O , . . . O O X O X X |
$$ | X X X O . O . . . . O . . O . O X X . |
$$ | X O O . . O . . . . . . . . . O X O X |
$$ | . X . O O . . . . . . . . . . O O O O |
$$ +---------------------------------------+[/go]


Although I doubt I can justify continuing this game much longer. It's silly to resign when I might get something out of this ko (and there are still big openish areas on the board), but I'm sure I can't get remotely enough if 1986 handles it right. This move is obviously forced (perhaps this time I would even be justified in saying that no thought is required ;-)), so no more comment needed.

I bet Ed sticks in a hidden comment now just to make me feel paranoid :lol:

Re: 115 - robinz v. 1986

Posted: Fri Jul 15, 2011 3:34 pm
by jts
"A three-step ko isn't a ko." Agree or disagree?

Posted: Fri Jul 15, 2011 3:35 pm
by EdLee
jts wrote:"A three-step ko isn't a ko." Agree or disagree?
Here it's very good for W. :)

Re: 115 - robinz v. 1986

Posted: Sat Jul 16, 2011 1:00 am
by 1986
Click Here To Show Diagram Code
[go]$$Wcm202 Prisoner Count :w29: :b11:
$$ +---------------------------------------+
$$ | . . . . . . . X . X . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . X O . . O . . X X X |
$$ | . . O . O . . . . O . O O . O X . . X |
$$ | . . O X . . . . . . . . . . . X X X . |
$$ | . O X O O O O . . . . . . . X . X . X |
$$ | . O X X . X X X . . . . . X . X . . . |
$$ | . . X , X . . . . , O . X X X X X . X |
$$ | . . X X X . . . . . . . X . . . X . X |
$$ | . X . O . . . . . . . O O X X . . . . |
$$ | X . O . X X X X . X . . . O X . X . . |
$$ | O O O . X O O X O . . . . O X X X X . |
$$ | X X O X . . . O X X . . O . O X . X . |
$$ | X . X O O O . . O , . . . O O X O X X |
$$ | X X X O . O . . . . O . . O . O X X . |
$$ | X O O . . O . . . . . . . . . O X O X |
$$ | . X 1 O O . . . . . . . . . . O O O O |
$$ +---------------------------------------+[/go]


this moved was forced based on the capturing race going on in the corner

Re: 115 - robinz v. 1986

Posted: Sat Jul 16, 2011 3:40 am
by robinz
Click Here To Show Diagram Code
[go]$$Bcm203 Prisoner Count :w29: :b11:
$$ +---------------------------------------+
$$ | . . . . . . . X . X . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . X O . . O . . X X X |
$$ | . . O . O . . . . O . O O . O X . . X |
$$ | . . O X . . . . . . . . . . . X X X . |
$$ | . O X O O O O . . . . . . . X . X . X |
$$ | . O X X . X X X . . . . . X . X . . . |
$$ | . . X , X . . . . , O . X X X X X . X |
$$ | . . X X X . . . . . . . X . . . X . X |
$$ | . X 1 O . . . . . . . O O X X . . . . |
$$ | X . O . X X X X . X . . . O X . X . . |
$$ | O O O . X O O X O . . . . O X X X X . |
$$ | X X O X . . . O X X . . O . O X . X . |
$$ | X . X O O O . . O , . . . O O X O X X |
$$ | X X X O . O . . . . O . . O . O X X . |
$$ | X O O . . O . . . . . . . . . O X O X |
$$ | . X O O O . . . . . . . . . . O O O O |
$$ +---------------------------------------+[/go]


Again, not much choice here - it was this or D7, and both are essentially dame points, whatever the result of the ko :sad:, but I think this one has the greater chance actually worth a point. Although I really don't think it matters much, if at all.

It's time to start thinking about which ko threat I should use first - I have several promising ones (which is good, as I desparately need them!). G18 is clearly a huge move in its own right, as well as having some largeish followups (H16 and E18 spring to mind), but I'm not sure if those followups are large enough. P2 threatens to capture 7 stones, so must come in for consideration too. And I'm sure there are others. I suspect it'll be G18, though, as I think it also gives me later ko threats involving using the aji of D13.

Re: 115 - robinz v. 1986

Posted: Sat Jul 16, 2011 4:50 am
by 1986
Click Here To Show Diagram Code
[go]$$Wcm204 Prisoner Count :w29: :b11:
$$ +---------------------------------------+
$$ | . . . . . . . X . X . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . X O . . O . . X X X |
$$ | . . O . O . . . . O . O O . O X . . X |
$$ | . . O X . . . . . . . . . . . X X X . |
$$ | . O X O O O O . . . . . . . X . X . X |
$$ | . O X X . X X X . . . . . X . X . . . |
$$ | . . X , X . . . . , O . X X X X X . X |
$$ | . . X X X . . . . . . . X . . . X . X |
$$ | . X X O . . . . . 1 . O O X X . . . . |
$$ | X . O . X X X X . X . . . O X . X . . |
$$ | O O O . X O O X O . . . . O X X X X . |
$$ | X X O X . . . O X X . . O . O X . X . |
$$ | X . X O O O . . O , . . . O O X O X X |
$$ | X X X O . O . . . . O . . O . O X X . |
$$ | X O O . . O . . . . . . . . . O X O X |
$$ | . X O O O . . . . . . . . . . O O O O |
$$ +---------------------------------------+[/go]


this move was inspiried by ez4u's game it looks like something he would play i dont know how to fish though, i was going to play f18 because u know i been thinking about e18, but the center looks more important right now so i will see if i can get f18 in later  

Re: 115 - robinz v. 1986

Posted: Sat Jul 16, 2011 5:03 am
by robinz
Click Here To Show Diagram Code
[go]$$Bcm205 Prisoner Count :w29: :b11:
$$ +---------------------------------------+
$$ | . . . . . . . X . X . O . . . . . . . |
$$ | . . . . . . . O X . . O X X X . . . . |
$$ | . . . . O X . O X . X X O O O O O O . |
$$ | . . . O . X . . . X X O O X X X X O . |
$$ | . . . . . . . O . X O . . O . . X X X |
$$ | . . O . O . . . . O . O O . O X . . X |
$$ | . . O X . . . . . . . . . . . X X X . |
$$ | . O X O O O O . . . . . . . X . X . X |
$$ | . O X X . X X X . . . . . X . X . . . |
$$ | . . X , X . . . . , O . X X X X X . X |
$$ | . . X X X . . . . . . . X . . . X . X |
$$ | . X X O . . . . . O . O O X X . . . . |
$$ | X . O 1 X X X X . X . . . O X . X . . |
$$ | O O O . X O O X O . . . . O X X X X . |
$$ | X X O X . . . O X X . . O . O X . X . |
$$ | X . X O O O . . O , . . . O O X O X X |
$$ | X X X O . O . . . . O . . O . O X X . |
$$ | X O O . . O . . . . . . . . . O X O X |
$$ | . X O O O . . . . . . . . . . O O O O |
$$ +---------------------------------------+[/go]


Eh? I'm very surprised - why didn't he take the ko? OK, that move isn't exactly small, but not only is it surely not the biggest move on the board (G18 must win that prize, or at least come very close), it totally ignores the ko. Now it's only a 2-step ko for me as opposed to a 3-step - yes, that's still bad, but it's a lot less bad than it might have been.
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