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Intra Ranch Go Game!

Bert Bates
author
Sheriff

Joined: Oct 14, 2002
Posts: 8815
    
    5
w j7 - and here I thought we were doing a furikawari


Spot false dilemmas now, ask me how!
(If you're not on the edge, you're taking up too much room.)
Ryan McGuire
Ranch Hand

Joined: Feb 18, 2005
Posts: 1007
    
    3
I'll move later. I just wanted to get the pictures as close to the top of page 5 as possible.

Moves 1-100:


Moves 101 on

Prisoners taken: White: 1, Black: 1

[ April 27, 2006: Message edited by: Ryan McGuire ]
[ May 03, 2006: Message edited by: Ryan McGuire ]
Bert Bates
author
Sheriff

Joined: Oct 14, 2002
Posts: 8815
    
    5
Thanks Ryan,

For those of you following along I thought I'd define a few terms:

furikawari - the swapping of large scale groups and/or territories. For instance, the white group in the lower right side is almost certainly lost, but white is hoping that, in exchange for that loss, he'll get a few stones and some territory in the center...kind of a horse trade.

aji - the potential of (often almost dead) trapped stones. The almost dead white stones on the right side have aji, because if white could have two moves in a row, he could perhaps save them. At some point in the future, a Ko fight might be started. When a move that's a Ko threat in a Ko fight is ignored, a player can, in effect, get two moves in a row in a local situation. This is just a small potential at this point, it's nothing that black wants to spend time squishing right now, he has bigger fish to fry, so it will remain on the board as a small potential until much later...
Ryan McGuire
Ranch Hand

Joined: Feb 18, 2005
Posts: 1007
    
    3
b - L8

I'll be offline over the weekend. See ya Monday.

Note to self: Keep counting liberties on the center black group. Make sure you have enough to kill S4, etc.
Bert Bates
author
Sheriff

Joined: Oct 14, 2002
Posts: 8815
    
    5
w - k7
Ryan McGuire
Ranch Hand

Joined: Feb 18, 2005
Posts: 1007
    
    3
I just can't take it any more!!!

b - d2

<pant pant/> There, I feel better now.
Bert Bates
author
Sheriff

Joined: Oct 14, 2002
Posts: 8815
    
    5
Welcome back Ryan,

w - c2
fred rosenberger
lowercase baba
Bartender

Joined: Oct 02, 2003
Posts: 11352
    
  16

in case you were wondering, there is at least one person following along.

not that i understand all the strategy, but i do try to figure out why you both are making the moves you are...


There are only two hard things in computer science: cache invalidation, naming things, and off-by-one errors
Bert Bates
author
Sheriff

Joined: Oct 14, 2002
Posts: 8815
    
    5
That's cool Fred - it would be great to hear your comments and questions! This is kind of an open teaching game after all
fred rosenberger
lowercase baba
Bartender

Joined: Oct 02, 2003
Posts: 11352
    
  16

well, strategy is really lost on me. like chess, i understand the rules, and have a BASIC idea of strategy (two eyes are good, the middle is hard to control, etc).

but some things are lost on me. how do you KNOW that "the white group in the lower right side is almost certainly lost". i assume you are talking about the group that contains O5...

how would two moves in a row garantee their safety?

why did black choose D2, instead of, say, E2? that stone is now hanging off by itself. white could now play at E2, and if black tries to surround those, wouldn't white just keep playing down to connect to K3?

although, i THINK i see how black would end that... by playing at F2, white can't get around to meet his other stones. but (and this is probably just my lack of experience) i think there would be a battle down there, each side trying to gain a stone or two. it wouldn't be too hard to get something down there in Atari, i just can't see who would end up winning...

Now, aren't you sorry you asked for my questions?
[ April 03, 2006: Message edited by: fred rosenberger ]
Bert Bates
author
Sheriff

Joined: Oct 14, 2002
Posts: 8815
    
    5
well, strategy is really lost on me. like chess, i understand the rules, and have a BASIC idea of strategy (two eyes are good, the middle is hard to control, etc).

but some things are lost on me. how do you KNOW that "the white group in the lower right side is almost certainly lost". i assume you are talking about the group that contains O5...


well the o5 group doesn't have any eyes and only 3 liberties - it's looking very sad - it's in a competition with black's o8 group, but while black's o8 group doesn't officially have any eyes yet it has 6 or 7 liberties

how would two moves in a row garantee their safety?


imagine if white could play s6 and s7...

why did black choose D2, instead of, say, E2? that stone is now hanging off by itself. white could now play at E2, and if black tries to surround those, wouldn't white just keep playing down to connect to K3?

although, i THINK i see how black would end that... by playing at F2, white can't get around to meet his other stones. but (and this is probably just my lack of experience) i think there would be a battle down there, each side trying to gain a stone or two. it wouldn't be too hard to get something down there in Atari, i just can't see who would end up winning...


Like in software there are repeating "patterns" (they're called "shapes") in Go. A lot of these shapes occur on the 2nd and 3rd lines (from the edge), and with some practice you just come to see which ones will work and which ones won't work. In this case it "won't work for black to play e2 - one way to determine this is to count the liberties (open adjacent spaces) of the two competing stones. For example, if white played e2, then his e2 stone would have 2 liberties and black's d2 stone would have 2 liberties, BUT it's black's turn, so if he played f2 white would be down to 1 liberty and "behind in the liberty race". This is twice that "liberty races" have come up in this thread - these liberty race calculations happen all the time, almost at every move...

Now, aren't you sorry you asked for my questions?


No, this is fun to talk about!
Mark Spritzler
ranger
Sheriff

Joined: Feb 05, 2001
Posts: 17250
    
    6

Still sounds like French to me. I just like looking at the pretty picture with the stones.

Mark


Perfect World Programming, LLC - Two Laptop Bag - Tube Organizer
How to Ask Questions the Smart Way FAQ
fred rosenberger
lowercase baba
Bartender

Joined: Oct 02, 2003
Posts: 11352
    
  16

I just like looking at the pretty picture with the stones.

i agree on that. i think Go is one of the prettiest games to watch or just look at.
Ryan McGuire
Ranch Hand

Joined: Feb 18, 2005
Posts: 1007
    
    3
Your move at c2 was obvious enough that I should have pre-loaded this move, which also should be no surprise to anyone.

B - e1

But I will admit that I'm not exactly sure what White will do next.

Originally posted by Mark Spritzler:
Still sounds like French to me. I just like looking at the pretty picture with the stones.


So start making some of your own.
Bert Bates
author
Sheriff

Joined: Oct 14, 2002
Posts: 8815
    
    5
Well I counted the board and it seems like there is no peaceful solution

It seems like if the black stones on the bottom left live, black will have more territory

So white has to see if he can kill those black stones


w - f2

black has a couple of ways to prevent w-e2, if black does choose to prevent w-e2, then w - j2

Seems like the furikawari continues!

For those of you keeping score at home, for white to succeed in killing the black stones, he has to make sure that black can only get one eye. (An eye is a surrounded space like at n18, although an eye can be bigger, it can be up to 5 contiguous surrounded open spaces. If black can break up the space his stones are surrounding into 2 separate spaces (eyes) then he will live. The other possibility for black is that if he can capture any of the white stones that are surrounding his group he will also be alive, and, in fact, some of the surrounding white stones have weaknesses.

White is making a gamble here. if black can capture any of the surrounding white stones, then white's big potential territory on the left side will probably be destroyed. This could be become an all or nothing kind of battle for white. White would prefer that the stakes weren't so high, but it seems that because of the score on the rest of the board, he has to fight this dangerous fight.
[ April 04, 2006: Message edited by: Bert Bates ]
Ryan McGuire
Ranch Hand

Joined: Feb 18, 2005
Posts: 1007
    
    3
Indeed, the cut at Whites move 112 was freakin' huge. Looking back, I'm not sure I had to play 111 in the corner in order to keep White's eyeless group from getting away. Heck, even better would have been to just connect at K3 when White played L3 back at moves 88 and 89. Oh well, hindsight is 20/20.

Now can I come up with a sequence where the last move threatens to take something big in the middle AND simultaneously takes away a vital liberty from one of White's little groups? Anyhow, I've updated the diagram, but I'm going to have to go meditate on top of a mountain somewhere to come up with the next move.

Re: The Furikawari
Depending on whether you considered the center of the board to be White's beforehand, the moves starting with the cut of move 79 have grabbed a pretty nice white group on the right side and spoiled some of White's center at the cost of pretty much the whole bottom side (assuming White kills those black stones). By my count, Black was behind and made up some* ground but still has a ways to go.

* "some": Given the way I was counting it before the cut, Black has gained 6-10 points, even if he loses the whole bottom side.
Bert Bates
author
Sheriff

Joined: Oct 14, 2002
Posts: 8815
    
    5
Indeed, the cut at Whites move 112 was freakin' huge. Looking back, I'm not sure I had to play 111 in the corner in order to keep White's eyeless group from getting away. Heck, even better would have been to just connect at K3 when White played L3 back at moves 88 and 89. Oh well, hindsight is 20/20.


I LOVE this quote. It really speaks to one of the coolest parts of Go. Playing Go is kind of like being one of those plate spinners that used to be on the Ed Sullivan show You know, they'd get a bunch of plates spinning on the tops of sticks, and pretty soon they'd be racing back and forth, trying to find the most urgent plate and re-spinning it. Playing a good game of Go can feel a lot like this - there are a bunch of groups that need attention, and you have to decide what's most urgent... so in this case black is lamenting that maybe the fight on the ride side wasn't the correct plate to spin at that moment, and perhaps the group on the bottom was more urgent.
Bert Bates
author
Sheriff

Joined: Oct 14, 2002
Posts: 8815
    
    5
Hey Ryan,

How are your supplies holding out, up there on top of the mountain?
Ryan McGuire
Ranch Hand

Joined: Feb 18, 2005
Posts: 1007
    
    3
Originally posted by Bert Bates:
Hey Ryan,

How are your supplies holding out, up there on top of the mountain?


Sorry.

I hate it when real life intrudes on a good game of Go. I just haven't had time to decide which plate I need to keep spinning, to use your metaphor.

And worse, I'm afraid I'm going to be incommunicado again until at least Thursday. If you can wait that long, great.

But again... I don't own the black stones.
[ April 09, 2006: Message edited by: Ryan McGuire ]
Bert Bates
author
Sheriff

Joined: Oct 14, 2002
Posts: 8815
    
    5
I don't own the white stones either, and I can certainly wait - there are books to be written
Ryan McGuire
Ranch Hand

Joined: Feb 18, 2005
Posts: 1007
    
    3
Well, I'm not finding the silver bullet move. I guess I'll spend a move or two thrashing around like a cornered wolverine.

B - O14 <Snarl/>
Bert Bates
author
Sheriff

Joined: Oct 14, 2002
Posts: 8815
    
    5
I guess I'll spend a move or two thrashing around like a cornered wolverine.


rofl That's a great image

w - m12

welcome back
Bert Bates
author
Sheriff

Joined: Oct 14, 2002
Posts: 8815
    
    5
Ryan McGuire
Ranch Hand

Joined: Feb 18, 2005
Posts: 1007
    
    3
The last thing I want to see is a from Bert. Unfortunately, I just don't see a light at the end of this tunnel. But that's never stopped me before.

B - j10

(I'll update the image some time soon.)
Ryan McGuire
Ranch Hand

Joined: Feb 18, 2005
Posts: 1007
    
    3
Originally posted by Ryan McGuire:

B - j10


Wait wait wait, I didn't take my finger off it yet.

B - j9 Yeah, that's the winning move.
Bert Bates
author
Sheriff

Joined: Oct 14, 2002
Posts: 8815
    
    5
w - k8 - still complicated!
fred rosenberger
lowercase baba
Bartender

Joined: Oct 02, 2003
Posts: 11352
    
  16

i'm not making a play, but i have just last night finished the first book by Janice Kim. i've got the second, and will probably read much of it this weekend.

i imagine the second one will go (pardon the pun) much slower, since more of it will be new to me.

I'm working on it. So this game, in addition to being fun for you guys, has inspired me to really learn.
Ryan McGuire
Ranch Hand

Joined: Feb 18, 2005
Posts: 1007
    
    3
Originally posted by Bert Bates:
w - k8 - still complicated!


Yup.

Black - k9.

Speaking of black canines*, we recently adopted an older greyhound. She was a basically a puppy factory for the last five years or so. She was in bad shape when we got her: one infected eye, bad teeth, various small wounds that hadn't healed, and (as the vet found while spaying her) a uterus full of cysts. Between the spaying, teeth cleaning, and eye exam on Monday, she's been in sad shape for a few days. She couldn't keep food or water down, which of course just prolonged the recovery period. She certainly couldn't go up or down stairs. Poor little doggy.

But she's feeling much better now. She ate full breakfast and dinner yesterday and went with us on a short walk around the block. She still doesn't like going up or down more than three or four stairs, but that's just standard post-spay tenderness.

* How's that for a segue?
Bert Bates
author
Sheriff

Joined: Oct 14, 2002
Posts: 8815
    
    5
w - L9 - cross-cut

L9 is called a "cross-cut" - it separates the stones in the vicinity into separate groups. Whenever this happens it causes a lot of local tension because typically every group wants to live - so now there are newly formed groups all struggling for space to live

Wow - greyhounds! I've heard that those rescue greyhounds are amazingly great pets - loyal and appreciative to be in sane surrounding. congrats!
Ryan McGuire
Ranch Hand

Joined: Feb 18, 2005
Posts: 1007
    
    3
B - m8.

Otherwise the previous handful of moves would be meaningless.
Bert Bates
author
Sheriff

Joined: Oct 14, 2002
Posts: 8815
    
    5
wow! very delicate...

w - h 10
Ryan McGuire
Ranch Hand

Joined: Feb 18, 2005
Posts: 1007
    
    3
Originally posted by Bert Bates:
wow! very delicate...

w - h 10


Ooh, nice move. I was expecting j11, but if I try to cut through there now, I start with one fewer liberties.

Well let's see what I can rescue.

b - L7

I have a lot of things I want to do, but I've got make sure that I attempt them in the right order. Delicate indeed.
Bert Bates
author
Sheriff

Joined: Oct 14, 2002
Posts: 8815
    
    5
Hey!

I spent a lot of time trying to capture those 3 stones!

w - L6
Ryan McGuire
Ranch Hand

Joined: Feb 18, 2005
Posts: 1007
    
    3
b - m4 atari

Can I at least have one or two of these?
Bert Bates
author
Sheriff

Joined: Oct 14, 2002
Posts: 8815
    
    5
well there are certain stones i'm less attached to

w - L 4
Ryan McGuire
Ranch Hand

Joined: Feb 18, 2005
Posts: 1007
    
    3
I don't know if this is the biggest thing I can do right now, but taking this stone means I don't have to play in my own territory to take those white stones on right side. (just trying to reationalize it to myself)

b - n3

With any luck, white will feel forced to play in this area again, thus giving me the first move somewhere else.
Bert Bates
author
Sheriff

Joined: Oct 14, 2002
Posts: 8815
    
    5
yeah - i think it's a good move for the reasons you stated, but I don't think it's sente (famous last words )

w - d5

let's just make sure everything is secure over in this area - lot's is riding on making sure all those dead stones stay dead
Ryan McGuire
Ranch Hand

Joined: Feb 18, 2005
Posts: 1007
    
    3
Even with optimistic counting, black is behind by about 20. The only way to close that gap is to steal some of the territory that looks white now. Some of the moves coming up might not work and may even give white some extra prisoners/points. Well black can either play nice and definitely lose, or he can try some desparation moves and maybe pull out a win.

First, though, let's see if white sees this as forcing:

black - b17
Bert Bates
author
Sheriff

Joined: Oct 14, 2002
Posts: 8815
    
    5
I think Black's last move is big endgame, but not really sente - almost sente - so white owes black a move in the upper left...

White hopes that his move is a little bit bigger... so it's kind of like playing chicken

w - G 13
Ryan McGuire
Ranch Hand

Joined: Feb 18, 2005
Posts: 1007
    
    3
black - h12

If we're going to have a few quickfire moves here, I'm not going to bother updating the image each time.
 
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