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Vulnerable groups : memorised or re-analysed ?
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Author:  Chaa006 [ Tue Jan 11, 2011 9:35 am ]
Post subject:  Vulnerable groups : memorised or re-analysed ?

Although I have been playing Go on and off for over 30 years, and reached about 5 kyu when I was playing very regularly, I still regard myself as a beginner who just happens to know the rules and a little of the strategy. And just recently I have re-started playing Go against the computer : at first SmartGo, then The Many Faces of Go, and now I am considering investing in a copy of Zen19. But when I play against the computer, I am surprised at the number of times that I fail to recognise that the computer's move has converted what had been a vulnerable-but-salvageable group into a group that has no viable future. In part, I understand what is happening : because I have been playing sufficiently long to know that I do not necessarily need to capture a potentially dangerous stone as soon as it is played, I tend to end up with quite a few isolated groups, each of which is vulnerable yet which could be saved so long as I remember what I need to do. Yet time and time again, the computer plays a second stone against a vulnerable group, I fail to spot the danger, and "bang", the group is dead. So my question is : what do good players do concerning vulnerable groups ? Do they remember them, so that as soon as a stone is placed in proximity they go on red alert ? Or do they simply re-analyse both the local and the global situation every time an opponent's stone is played ?

Author:  topazg [ Tue Jan 11, 2011 9:44 am ]
Post subject:  Re: Vulnerable groups : memorised or re-analysed ?

Chaa006 wrote:
Although I have been playing Go on and off for over 30 years, and reached about 5 kyu when I was playing very regularly, I still regard myself as a beginner who just happens to know the rules and a little of the strategy. And just recently I have re-started playing Go against the computer : at first SmartGo, then The Many Faces of Go, and now I am considering investing in a copy of Zen19. But when I play against the computer, I am surprised at the number of times that I fail to recognise that the computer's move has converted what had been a vulnerable-but-savable group into a group that has no viable future. In part, I understand what is happening : because I have been playing sufficiently long to know that O do not necessarily need to capture a potentially dangerous stone as soon as it is played, I tend to end up with quite a few isolated groups, each of which is potentially vulnerable yet which could be saved so long as I remember what I need to do. Yet time and time again, the computer plays a second stone against a vulnerable group, I fail to spot the danger, and "bang", the group is dead. So my question is : what do good players do concerning vulnerable groups ? Do they remember them, so that as soon as a stone is placed in proximity they go on red alert ? Or do they simply re-analyse both the local and the global situation every time an opponent's stone is played ?


Honest answer? Both :)

Though, in truth, "Having lots of vulnerable groups" sounds more like the source of your problems. I'm very unhappy if I have 3 unsettled groups on the board at any one time.

Author:  daniel_the_smith [ Tue Jan 11, 2011 10:00 am ]
Post subject:  Re: Vulnerable groups : memorised or re-analysed ?

Chaa006 wrote:
... I tend to end up with quite a few isolated groups ...


I think I found your problem.

"Five might live but the sixth is dead."

If you're busy making eyes, you aren't winning the game...

Author:  Chaa006 [ Tue Jan 11, 2011 10:01 am ]
Post subject:  Re: Vulnerable groups : memorised or re-analysed ?

topazg wrote:
Honest answer? Both :) Though, in truth, "Having lots of vulnerable groups" sounds more like the source of your problems. I'm very unhappy if I have 3 unsettled groups on the board at any one time.

OK, so am I being over-ambitious ? I do try to win all four corners in every game, and then use those as bases from which to contest the centre. Would you advise me to be more modest in my ambitions, and allow my opponent one corner so that I have fewer vulnerable groups to worry about ?

daniel_the_smith wrote:
"Five might live but the sixth is dead."

Ah, I haven't got to that one yet in "Go Proverbs Illustrated" : I shall rush upstairs and see what it has to say on that topic. Thank you !

Author:  topazg [ Tue Jan 11, 2011 10:05 am ]
Post subject:  Re: Vulnerable groups : memorised or re-analysed ?

Chaa006 wrote:
topazg wrote:
Honest answer? Both :) Though, in truth, "Having lots of vulnerable groups" sounds more like the source of your problems. I'm very unhappy if I have 3 unsettled groups on the board at any one time.

OK, so am I being over-ambitious ? I do try to win all four corners in every game, and then use those as bases from which to contest the centre. Would you advise me to be more modest in my ambitions, and allow my opponent one corner so that I have fewer vulnerable groups to worry about ?


Yeah, sounds like you're being "greedy". Go is fundamentally a game where you have to give and take, and just try to take a tiny bit more than you give.

If you have 4 corners in a game, either your opponent has done something very badly wrong, or you have. Certainly, 4 corners + the center isn't going to happen :P

There's nothing wrong with having 2 corners each, but I think more importantly than that is "connect or settle any groups that you want alive that aren't yet already completely alive". Do that, and if you still get to take all those corners, go ahead :)

Author:  entropi [ Tue Jan 11, 2011 10:06 am ]
Post subject:  Re: Vulnerable groups : memorised or re-analysed ?

I am not a good player but I will still give my two cents.

I think the ideal answer should be re-analysed because if you have to "remember" the local position, it means there has been a lot going on since you left your vulnarable group alone. Since the whole board position has changed, it may be the case that you have to handle your weak group in another way that you could not have foreseen before. For example new possibilities for saving it may have arised for saving the group, or giving it up for something else could be more profitable in that new board position, etc.

Author:  Chaa006 [ Tue Jan 11, 2011 10:18 am ]
Post subject:  Re: Vulnerable groups : memorised or re-analysed ?

OK, my thanks to all for those very quick replies. Just one point of clarification :

topazg wrote:
Certainly, 4 corners + the center isn't going to happen :P

When I spoke of trying to win all four corners and then using those as a base from which to contest the centre, I meant by that last phrase not "gain further territory" but rather "prevent my opponent from gaining sufficient territory in the centre that he can win despite the fact that I hold all four corners".

Author:  topazg [ Tue Jan 11, 2011 10:23 am ]
Post subject:  Re: Vulnerable groups : memorised or re-analysed ?

Chaa006 wrote:
OK, my thanks to all for those very quick replies. Just one point of clarification :

topazg wrote:
Certainly, 4 corners + the center isn't going to happen :P

When I spoke of trying to win all four corners and then using those as a base from which to contest the centre, I meant by that last phrase not "gain further territory" but rather "prevent my opponent from gaining sufficient territory in the centre that he can win despite the fact that I hold all four corners".


Yes, that makes a lot of sense, but even restricted to that, it's a bit on the optimistic side :) Of course, the other question is what exactly do you mean by "get all 4 corners"?

Author:  Chaa006 [ Tue Jan 11, 2011 10:39 am ]
Post subject:  Re: Vulnerable groups : memorised or re-analysed ?

topazg wrote:
the other question is what exactly do you mean by "get all 4 corners"?

Oh, just to have a live group in each, so that A1, A19, T1 & T19 are all within my territory rather than my opponent's or neutral. In fact, looking back at my last game (which I won : MFoG resigned at 107,5 points down, with 245 stones played), I hold only three corners !

Author:  snorri [ Tue Jan 11, 2011 11:04 am ]
Post subject:  Re: Vulnerable groups : memorised or re-analysed ?

It happens to me, too, when I stop playing for a while. There is a sense of the board that one gets from regular play that seems to get out of whack. I think part of it is the ability to keep track of weaknesses on both sides. A go "spidey-sense" if you will.

I've long felt that that one of the first things that beginners learn once they move to a 19x19 board is just paying attention. It's not so much missing tesujis or reading mistakes. It's more along the lines of just being too wrapped up in a local position to understand what's going on on the whole board.

I find it helps to get back in the habit of pausing and looking at the whole board before every move. I try to take the point of view of my opponent or of a stronger bystander.

In chess they have studied eye movements by strong and weak players. One difference is that the stronger players spend most of their time thinking about where their opponent can play, not where they themselves can play. I think the greedy play habit results from not taking time to think from your opponent's perspective.

I am a naturally aggressive player. When I think from my opponent's point of view I also think agressively, so I am much more likely to see my own weaknesses and play patiently. But if I am tired or playing to fast or just out of practice, it's all to easy to lose that good habit.

Author:  Dusk Eagle [ Tue Jan 11, 2011 11:35 am ]
Post subject:  Re: Vulnerable groups : memorised or re-analysed ?

There's a balance between the value of the corner and the center. Just grabbing the corner at any cost can very often be very bad. For instance, in my last game I played, the following sequence occurred at the beginning of the game (I'm white):



This result is absolutely terrible for black. He has - count them - five points of territory in the corner (including the capture), and is completely sealed in. His one stone on the outside is not worth much at all, and at this point in the game was rightly given up by my opponent. White has incredible influence in all directions. I ended up winning the game by 49.5 points.

My point in saying that is to demonstrate how flawed a strategy it is to aim exclusively for the corners and then just try to live in the center. Corners are valuable, yes, but there is a balance between the corner, the side, and the center which cannot be ignored.

Anyway, that was meant to be a quick secondary point, rather than the main one :oops: . I think one of the things that has struck me most as I get stronger is what I focus on when I look at the board. It used to be that I was always looking for the widest spot on the board, and I would place a stone there trying to either make more territory or destroy some of my opponents. However, once I got to around 3-5k, I started to develop this new sense when looking at the board - I could sense which groups were weak and needed help. I don't mean necessarily that they would definitely die if left alone one more turn, I only mean my opponent could launch a severe attack on them, and thus claim profit while attacking. Now, when I sense a weak group of mine, my thoughts are usually "What is the best way I can play to make this group stronger?" Or, if I think my opponent can make my group weak with one more move, I aim to strengthen it up before he can do that.

My point is, a large part of Go is keeping your own groups strong and attacking your opponent's groups when they get weak. If you noticed, both topazg and daniel_the_smith touched on the sentence below, and I will too. Without actually being able to see a game of yours, I would guess it's a big part of your problems:
Quote:
I tend to end up with quite a few isolated groups, each of which is potentially vulnerable yet which could be saved so long as I remember what I need to do.

If your group is weak and isolated, don't go creating more weak and isolated groups. Strengthen up your group first (good moves being extending along the side, or if there's no more room, a one-space jump into the center), and then you can start a new group somewhere else.

Author:  illluck [ Tue Jan 11, 2011 11:47 am ]
Post subject:  Re: Vulnerable groups : memorised or re-analysed ?

When I'm reading to see if a group can be killed and find that it can live, I also try to see what moves would change the status of the group (if I'm attacking, I will try to make those points profitable, if I'm defending, I have to make sure that the opponent can't make dual-threats with those points).

Author:  Chaa006 [ Tue Jan 11, 2011 11:48 am ]
Post subject:  Re: Vulnerable groups : memorised or re-analysed ?

Dusk Eagle wrote:
(snip)My point is, a large part of Go is keeping your own groups strong and attacking your opponent's groups when they get weak. If you noticed, both topazg and daniel_the_smith touched on the sentence below, and I will too. Without actually being able to see a game of yours, I would guess it's a big part of your problems

OK, understood, thank you. I found it interesting that in the game you attached, all the opening moves were in a single corner; this is not something I have seen since I was a complete beginner, and all of my games against the computer have started with B & W each taking two corners, after which I (as B) start to attack the corners in which my opponent has a single stone and to defend my own against any attack that he (the computer) makes. I'd be very happy to send you an SGF file, but I am a little reluctant to post it on the forum because I know only too well that it contains many weak moves on my part !

P.S. Daniel-the-Smith : I have just looked for "Five might live but the sixth is dead." in Go Proverbs Illustrated, but can't find it; obviously there must be a very large number of Go proverbs, so not all could possibly be included, but I wonder if you remember where you came across that one ?

Author:  Li Kao [ Tue Jan 11, 2011 12:06 pm ]
Post subject:  Re: Vulnerable groups : memorised or re-analysed ?

What Dusk Eagle posted was most likely not the beginning of the game, but only the part that happened in one corner.

And you don't need to be ashamed of posting a game because it contains weak moves. That just creates more opportunity for us to give you tips for improvement. And remember: Almost every go player considers himself weak. Think about improving instead of being ashamed of your weakness.

Author:  Chaa006 [ Tue Jan 11, 2011 12:17 pm ]
Post subject:  Re: Vulnerable groups : memorised or re-analysed ?

Li Kao wrote:
What Dusk Eagle posted was most likely not the beginning of the game, but only the part that happened in one corner.
Ah, didn't think of that possibility. But presumably it must have been very early on, because the A1 corner was completely unpopulated at the start of the sequence.
Quote:
And you don't need to be ashamed of posting a game because it contains weak moves. That just creates more opportunity for us to give you tips for improvement. And remember: Almost every go player considers himself weak. Think about improving instead of being ashamed of your weakness.
I'll try : I just don't like feeling embarrassed :) But is there a sandbox on the forum in which one can practice uploading games, as this would be my first attempt at such a thing ?

Author:  judicata [ Tue Jan 11, 2011 12:57 pm ]
Post subject:  Re: Vulnerable groups : memorised or re-analysed ?

First, to end speculation on the game Dusk Eagle posted, here are the first several moves of that game (I've removed the opponents name, although the entire game is publicly available):



It appears the sequence was played pretty early, and looks very good for white.

Don't be embarassed--it will prevent improvement. As others have said, don't place too much emphasis on the corners. Although the corners are the easiest place to create territory, "capturing" some points in the corner does not come without a cost. Besides, if you really want to make territory in the corners you open in (i.e., the corners you play in first) open on the 3-3 point.

I would also encourage you to play some real people--don't let embarassment hold you back!

Finally, as far as a "sandbox" you can experiment posting a game here in this thread--you won't break anything.

Author:  hyperpape [ Tue Jan 11, 2011 1:14 pm ]
Post subject:  Re: Vulnerable groups : memorised or re-analysed ?

Chaa006 wrote:
I'll try : I just don't like feeling embarrassed :) But is there a sandbox on the forum in which one can practice uploading games, as this would be my first attempt at such a thing ?


Just in case you hadn't seen it, here are instructions: viewtopic.php?f=14&t=833.

Author:  Chaa006 [ Tue Jan 11, 2011 1:15 pm ]
Post subject:  Re: Vulnerable groups : memorised or re-analysed ?

judicata wrote:
First, to end speculation on the game Dusk Eagle posted, here are the first several moves of that game (I've removed the opponents name, although the entire game is publicly available):

It appears the sequence was played pretty early, and looks very good for white.

Don't be embarassed--it will prevent improvement. As others have said, don't place too much emphasis on the corners. Although the corners are the easiest place to create territory, "capturing" some points in the corner does not come without a cost. Besides, if you really want to make territory in the corners you open in (i.e., the corners you play in first) open on the 3-3 point.

I would also encourage you to play some real people--don't let embarassment hold you back!

Finally, as far as a "sandbox" you can experiment posting a game here in this thread--you won't break anything.
OK, many thanks. All advice heeded and taken on board. I have played real people in the past (many of them : Brian Chandler, Stuart Dowsey and Alan Fairbourn were probably the highest graded players I ever had the privilege of playing against), but at the moment I am playing table tennis against real people and Go against the computer when I am stuck indoors !

I have attached my most recent game against MFoG, basically because I can conceal my embarrassment at my awful moves behind the satisfaction of having won :)

Hyperpape : many thanks for the link; it arrived just after I'd pressed "Submit" but I think I have done it correctly ...


Author:  daniel_the_smith [ Tue Jan 11, 2011 2:17 pm ]
Post subject:  Re: Vulnerable groups : memorised or re-analysed ?

Chaa006 wrote:
P.S. Daniel-the-Smith : I have just looked for "Five might live but the sixth is dead." in Go Proverbs Illustrated, but can't find it; obviously there must be a very large number of Go proverbs, so not all could possibly be included, but I wonder if you remember where you came across that one ?


Here's one place: http://senseis.xmp.net/?path=GoProverbs ... xthWillDie

Proverbs aren't meant to be too deep, IMO; the main point is that you don't have time to make a bunch of separate groups live individually.

---

A situation where you have to keep track of all your opponent's sente moves against your groups is inferior to one where you don't, all other things being equal. The solution isn't to start keeping better track of these moves; the solution is to stay out of positions where your opponent has them at all. (A few are unavoidable, probably, but you should take great pains to minimize them...)

Another thing to think about: sente moves like that are very likely to be unignorable ko threats. It doesn't take too many of them to get into a position where you both know your opponent will win any ko. At that point, any sticky situation becomes favorable to your opponent, since they just have to make ko.

Author:  Chaa006 [ Tue Jan 11, 2011 2:32 pm ]
Post subject:  Re: Vulnerable groups : memorised or re-analysed ?

daniel_the_smith wrote:
Here's one place: http://senseis.xmp.net/?path=GoProverbs ... xthWillDie
Proverbs aren't meant to be too deep, IMO; the main point is that you don't have time to make a bunch of separate groups live individually.(snip)
Thank you. I was thinking of treating myself to a copy of Milton Bradley's New Go Proverbs Illustrated as a late Christmas present, but maybe I should save my money and just read the Sensei's proverbs online :) (Not so easy to do in bed, 'though).

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