Leela Zero analysis of 'Making good shape' and other books.

[John Fairbairn]

What I think the bots have shown is that even the strongest players have been too opinionated about 'bad' positions even when they in fact don't understand them very well.

I don't think the bots have shown this as something new. One of the main characteristics of the series of books of commented game I have done (Kamakura, etc) is that the commentaries have been compiled on the basis of many pro sources, and I have shown many times that pros can disagree vehemently about all sorts of moves.

I have also demonstrated very many cases (usually thanks to Go Seigen) in Gateway To All Marvels where answers to tsumego problems by 9-dans are flawed.

There have been cases where 9-dans have made spectacular booboos in endgame problems (one by Kano Yoshinori spotted by Matthew Macfadyen comes to mind. I'm sure people can point to other examples, and of course we mustn't overlook the innumerable cases where a pro has made what he believed to be a good move only for it to turn out badly, and the likewise common cases where pro commentators claim to have found mistakes by even Go Seigen and Dosaku.

(But in the case of the problems here and similar books, I'm not convinced that the bots are necessarily showing even the strongest players are wrong, for the simple reason that there's a good chance that the books were in fact written by amateur ghost writers. Plus, of course, the book here is not about making the best move but about making good shape, which may be something rather different.)

Anyway, pros getting it wrong and this being pointed out is nothing new.

Yet we all feel the bots are telling us something new. Why, and what is it? I'm not at all. Maybe it's something to do with the frequency of apparent pro mistakes. Maybe they are not mistakes at all but a matter of style. If we allowed humans to play in such a way that they could somehow not make blunders and could play each move with a consistency that escapes them because of fatigue, carelessness or whatever - e.g. they could take back moves - would they sometimes beat bots (there have been enough close games with bots to suggest a small boost in the human style of play could earn victories).

Clearly, no-one knows the answers yet, but I think it's agreed that we now know humans must learn to consider more candidate moves. The other area we need to consider is evaluation. I would like to suggest a novel approach to that which I found by accident.

I too have tried posing problems from books to LZ, but the way I did it was to input the positions in a haphazard order and not in the order of play. What I noticed was that if you put, say, a move on the second line that had no proper relationship to the other stones, the winrate graph went berserk, but when you later add another stone which makes that stone relate sensibly to other stones, the winrate graph would flatten out again.

I then experimented a bit, and made a point of trying to randomise the input. What I further discovered is that you can effectively ignore the winrate. It is inherently flat anyway, because the position once completely input is close to level (being from a pro game). But if you instead look at the variation lines (which hitherto I have tended to ignore, and I infer others do, too), you can see how LZ is "thinking."

To give a specific example, we put Black and White stones down alternately with pondering "on" as you do this, and let White make the most sensible move suggested by LZ (but initially I kept White stones away from the Black ones). For Black we put down S3 then Q8 as the first moves in the lower right quadrant (there may be Black moves elsewhere, though). We essentially ask LZ how to "repair" this awful shape. It suggests (not necessarily in the very next moves being considered but in the variation lines shown) that N3 is a move it likes for Black. Now add another Black stone at S7 and again ask LZ how to repair this daft shape. This time it suggests M3 (or M4). We can infer several things from this. It appears to "think," for example, that the stone at S7, daft as it is, is adding enough strength to justify a bigger extension. It's not really saying that, of course, but it's demonstrating something in a way a human like me can talk about, both in terms of what I already know (that you extend from strength according to how strong the position is) but also in terms of what I don't know - or just don't think about - namely that the weird position of S7 and S2, which I would regard as so daft and useless as to be not worth thinking about, actually adds enough strength to justify a wider extension.

If you then add a White stone at N3 (stopping any extension), LZ flips rapidly between L3 (pincer) and P3 (tsume) for Black in the variation lines, creating a feeling that is "talking" to me, saying "I can't make my mind up about these two moves."

If you then add another daft Black stone at K5 and look at the later variations where Black gets to move first in this area, we see that it now clearly prefers tsume at P3. LZ apparently does not want to try to enclose the White stone and build thickness by bullying from the outside (which is what I would have done).

I don't have the time to examine these extreme positions systematically, but I can say from the little I've done that I do feel LZ is now talking to me in terms I can just about follow. Maybe others would like to experiment with this technique?

[Bill Spight]

But if you instead look at the variation lines (which hitherto I have tended to ignore, and I infer others do, too), you can see how LZ is "thinking."
{snip}

I don't have the time to examine these extreme positions systematically, but I can say from the little I've done that I do feel LZ is now talking to me in terms I can just about follow.

Wonderful and fascinating, John1

I am reminded about how much we have discovered about how the brain works by seeing how it acts after being damaged, by disease, strokes, or accidents. More power to you.

Edit: Or how much we learn about human vision from optical illusions. We don't have to assume that Leela Zero is right about the plays it comes up with in bizarre situations. After all, it has not been trained on them. But we can learn something about how LZ works. Brilliant, John!

[Calvin Clark]

I decided to put a few of the problems from 'Attacking and Defending Moyos' (same authors) into LZ. Leela Zero does find other moves it prefers over the book answers and there is one terrible move in the solution I have found so far, but sometimes I get the feeling this is partly because in the positions chosen it evaluates black as being significantly ahead (or behind) at the start of the position. This affects everything for a bot, maybe more so than for a human. The book answer should be pretty easy for players who have studied problems like this, but white's response surprised me a bit. And I would not have guessed where LZ wanted to play as black in this position, either.

I should say that while I enjoy this exercise, I respect the authors. They have done a great service for the English-speaking go community over many years, and so I do not intend to post more positions. Books like this teach a way of thinking, and practical ideas for amateurs, and do not presume to reveal the absolute truth. LZ also teaches a way of thinking that we can't completely understand, but it is also likely far from the truth.

$$B Problem 4. Black to play and expand moyo.
$$ ---------------------------------------
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$$ | . . . . . . . . O . . . . O . . . . . |
$$ | . . O , . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
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$$ | . . . , . . . . . , . . . . . X . . . |
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$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . X . . . . . . |
$$ | . . . O . X . . . , . . . . X X X . . |
$$ | . . . . . . . . . . . X . O . O O . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------

Click Here To Show Diagram Code

[go]$$B Problem 4. Black to play and expand moyo.
$$ ---------------------------------------
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$$ | . . . . . . . . O . . . . O . . . . . |
$$ | . . O , . . . . . , . . . . . X . . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . . . . . . . . . . . . . X . . . |
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$$ | . . . , . . . . . , . . . . . X . . . |
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$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . X . . . . . . |
$$ | . . . O . X . . . , . . . . X X X . . |
$$ | . . . . . . . . . . . X . O . O O . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

[Uberdude]

My policy network for this position (I expect a is the book answer, but I'd like to get b in sente first if I can). h is for giggles.

$$Bc Problem 4. Black to play and expand moyo.
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . e . . . . O . . . . O b . . . . |
$$ | . . O d c . . . h , . . . . . X . . . |
$$ | . . . . . . . . . . . . . W . . . . . |
$$ | . . . . . . . . . . . . . i . X . . . |
$$ | . . . . . . . . . . . . . a . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . X . . . |
$$ | . . . f . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . X . . . . . . |
$$ | . . . O . X . . . , . . . . X X X . . |
$$ | . . . g . . . . . . . X . O . O O . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------

Click Here To Show Diagram Code

[go]$$Bc Problem 4. Black to play and expand moyo.
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . e . . . . O . . . . O b . . . . |
$$ | . . O d c . . . h , . . . . . X . . . |
$$ | . . . . . . . . . . . . . W . . . . . |
$$ | . . . . . . . . . . . . . i . X . . . |
$$ | . . . . . . . . . . . . . a . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . X . . . |
$$ | . . . f . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . X . . . . . . |
$$ | . . . O . X . . . , . . . . X X X . . |
$$ | . . . g . . . . . . . X . O . O O . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

I just checked Elf v1, and it likes b and f most. f is only available because white made a one-space jump there instead of 2 space, which Elf would prefer a bit. With this kind of Takemiya moyo building you sometimes see black making the 2-space high approach and then 2-space jump in that corner. But most interesting thing for me was what Elf preferred for white's last move instead of the marked jump: p12 reduction. That kind of move is rarely on my radar but now that I think about it I recall Matthew Macfadyen 6d suggesting such ideas in similar positions.

[Bill Spight]

My policy network for this position (I expect a is the book answer, but I'd like to get b in sente first if I can). h is for giggles.

$$Bc Problem 4. Black to play and expand moyo.
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . e . . . . O . . . . O b . . . . |
$$ | . . O d c . . . h , . . . . . X . . . |
$$ | . . . . . . . . . . . . . W . . . . . |
$$ | . . . . . . . . . . . . . i . X . . . |
$$ | . . . . . . . . . . . . . a . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . X . . . |
$$ | . . . f . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . X . . . . . . |
$$ | . . . O . X . . . , . . . . X X X . . |
$$ | . . . g . . . . . . . X . O . O O . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------

Click Here To Show Diagram Code

[go]$$Bc Problem 4. Black to play and expand moyo.
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . e . . . . O . . . . O b . . . . |
$$ | . . O d c . . . h , . . . . . X . . . |
$$ | . . . . . . . . . . . . . W . . . . . |
$$ | . . . . . . . . . . . . . i . X . . . |
$$ | . . . . . . . . . . . . . a . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . X . . . |
$$ | . . . f . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . X . . . . . . |
$$ | . . . O . X . . . , . . . . X X X . . |
$$ | . . . g . . . . . . . X . O . O O . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

I just checked Elf v1, and it likes b and f most. f is only available because white made a one-space jump there instead of 2 space, which Elf would prefer a bit. With this kind of Takemiya moyo building you sometimes see black making the 2-space high approach and then 2-space jump in that corner. But most interesting thing for me was what Elf preferred for white's last move instead of the marked jump: p12 reduction. That kind of move is rarely on my radar but now that I think about it I recall Matthew Macfadyen 6d suggesting such ideas in similar positions.

$$Bc Problem 4. Black to play and expand moyo.
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . e . . . . O . . . . O b . . . . |
$$ | . . O d c . . . h , . . . . . X . . . |
$$ | . . . . . . . . . . . . . W . . . . . |
$$ | . . . . . . . . . . . . . i . X . . . |
$$ | . . . . . . . . . . . . . a . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , 1 . . . . , . . . . . X . . . |
$$ | . . . f . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . X . . . . . . |
$$ | . . . O . X . . . , . . . . X X X . . |
$$ | . . . g . . . . . . . X . O . O O . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------

Click Here To Show Diagram Code

[go]$$Bc Problem 4. Black to play and expand moyo.
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . e . . . . O . . . . O b . . . . |
$$ | . . O d c . . . h , . . . . . X . . . |
$$ | . . . . . . . . . . . . . W . . . . . |
$$ | . . . . . . . . . . . . . i . X . . . |
$$ | . . . . . . . . . . . . . a . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , 1 . . . . , . . . . . X . . . |
$$ | . . . f . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . X . . . . . . |
$$ | . . . O . X . . . , . . . . X X X . . |
$$ | . . . g . . . . . . . X . O . O O . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

As an expanding moyo move, I expect that "a" is the book answer. But I was glad to hear that Elf likes "f", because in a real game I have the suspicion that I would play . Viewed from the standpoint of mutual damage, I think it does more damage.

[zermelo]

What I think the bots have shown is that even the strongest players have been too opinionated about 'bad' positions even when they in fact don't understand them very well.

I don't think the bots have shown this as something new. One of the main characteristics of the series of books of commented game I have done (Kamakura, etc) is that the commentaries have been compiled on the basis of many pro sources, and I have shown many times that pros can disagree vehemently about all sorts of moves.

I have also demonstrated very many cases (usually thanks to Go Seigen) in Gateway To All Marvels where answers to tsumego problems by 9-dans are flawed.

Fair enough, John. Maybe this is not new for everyone but at least I have realised something new. Of course I’ve known too that pros have different opinions on joseki and whole board judgement etc. Maybe the new learning is just a quantitative difference. I now know better how much I should trust it when a strong player says something is ‘bad’.

Still I think this ties into what other stronger players have said. I recall Ke Jie said something like that he’s going to stop trusting any whole board intuition and only trust reading and calculation from now on, after the Alphago experience. And if I understood Fan Hui’s point in his Alphago lectures, where he likes to say that “You can play anything! Anything goes!”, he means exactly that many players have been too judgemental were they have no real understanding, and that Alphago taught something about this.

Regarding ‘making good shape’ and similar books, I can believe that I did not necessarily need a bot to make the same conclusion. Maybe if I had shown the positions to 10 pros that would give their honest opinions, they would have told that there are other ways to play, and the ‘failures’ are often quite ok. It is just not something I can easily do, and then people often don’t like to criticise there colleagues.

I want to add that I’m sure that the ‘Making good shape’ book has done much more good than harm to my go skills. I have just to some extent tried to use that kind of books incorrectly. In a life and death book where you can solve 70% of the problems, you can pretty much trust that you will be stronger when you can solve the last 30% too. I assumed that if I want to be strong I need to be able to solve all problems from ‘Making good shape’ too. Now I see that trying to get there was pointless.

I’ll reiterate my earlier conclusion: If a much stronger player says that something is good, you can trust that it is good enough for your games. If they say something is bad, don’t trust them, unless you can verify it by reading or calculation.

[Uberdude]

So this thread doesn't come across as a van Zeijst / Bozulich bash, I took a look at a problem from "Shuko: The Only Move" vol 2. These are a series of whole board problems from his study group in which he suggests better moves than the young [relative to him!] pros played in their games, so we can be pretty sure it's really the thoughts of the great Fujisawa Shuko and not a ghostwriter.

$$Bcm19 Problem 39: Takao Shinji 7p (black) vs Morita Michihiro 9p
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O O . O O O . O . . . . . . . . |
$$ | . . . , X . . X X X . . . . . , X . . |
$$ | . . X . . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . O . 1 . . . . . . . . . . . |
$$ | . . . , . . 2 3 . , . . . . . , . . . |
$$ | . . . X b 7 . 6 . . . . . . . . . . . |
$$ | . . . c a . 4 . . . . . . . . . . . . |
$$ | . . d . . . . . . . . . . . . . . . . |
$$ | . . . 5 . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+

Click Here To Show Diagram Code

[go]$$Bcm19 Problem 39: Takao Shinji 7p (black) vs Morita Michihiro 9p
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O O . O O O . O . . . . . . . . |
$$ | . . . , X . . X X X . . . . . , X . . |
$$ | . . X . . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . O . 1 . . . . . . . . . . . |
$$ | . . . , . . 2 3 . , . . . . . , . . . |
$$ | . . . X b 7 . 6 . . . . . . . . . . . |
$$ | . . . c a . 4 . . . . . . . . . . . . |
$$ | . . d . . . . . . . . . . . . . . . . |
$$ | . . . 5 . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]

Black has just peeped with 25. The question is should you just connect or resist? In the game Morita simply connected, whilst Shuko says counter-peeping at a is the only move. The point is if black connects at b that's a good exchange to make black heavy and set up d for later, whereas if you connect directly then later if you peep black will not connect but treat the peeping stone lightly (it's already done its job of reducing white's eyeshape) and just defend at c. This is a pretty common technique (and I managed to get this problem right, others are harder). Elf v1 basically agrees with this logic: connect is the instinct but counter-peep quickly is found and has higher win% but I didn't run it long enough on my weak computer to overtake in playouts. If black does connect to the counterpeep white gains 7% compared to directly connecting. Incidentally Elf has some quite different ideas to the pros about the flow of the fight following the h11 cap, basically it doesn't like the cap (prefers tenuki e.g. lower right) and then doesn't want to run (Shuko mentions e9 and f9 as possibilities as well as the kosumi, one of these happened in his Kisei title match) but just settle inside with c13.

In the actual game Morita simply connected. He did consider the counter-peep but was worried about a black resistance shown below. Shuko says it's complicated but playable for white as e breaks out if black attempts the fence of d. Elf agrees with Shuko this result is good for white, but sees quite a few better moves in the sequence, for example it sees white e5 extend as a huge 50% mistake because it's not sente and black f10 connect in reply would put white in big trouble (playing around with the variations of white the d5 push and cut it seems legit to me). Or e10 at e7 for sacrifice 10% diff.

$$Wcm26 Morita's worry
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O O . O O O . O . . . . . . . . |
$$ | . . . , X . . X X X . . . . . , X . . |
$$ | . . X . . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . O . X . . . . . . . . . . . |
$$ | . . . 5 4 c O X . , . . . . . , . . . |
$$ | . . . X 3 X . O . . . . . . . . . . . |
$$ | . . . 2 1 6 O . . . . . . . . . . . . |
$$ | . . . 0 7 8 . . . . . . . . . . . . . |
$$ | . . . X 9 e . . . . . . . . . . . . . |
$$ | . . . b a . . . . . . . . . . . . . . |
$$ | . . . X . d . . . , . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+

Click Here To Show Diagram Code

[go]$$Wcm26 Morita's worry
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O O . O O O . O . . . . . . . . |
$$ | . . . , X . . X X X . . . . . , X . . |
$$ | . . X . . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . O . X . . . . . . . . . . . |
$$ | . . . 5 4 c O X . , . . . . . , . . . |
$$ | . . . X 3 X . O . . . . . . . . . . . |
$$ | . . . 2 1 6 O . . . . . . . . . . . . |
$$ | . . . 0 7 8 . . . . . . . . . . . . . |
$$ | . . . X 9 e . . . . . . . . . . . . . |
$$ | . . . b a . . . . . . . . . . . . . . |
$$ | . . . X . d . . . , . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]

Takao said he would have cut in response to the counter-peep. Shuko says that's no good as white is good with the squeeze, Elf strongly agrees (30% mistake) and agrees with the one-way-street given.

$$Wm26 Takao's plan
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O O . O O O . O . . . . . . . . |
$$ | . . . , X . . X X X . . . . . , X . . |
$$ | . . X . . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . O . X . . . . . . . . . . . |
$$ | . . . , . 9 O X . , . . . . . , . . . |
$$ | . . . X 3 X 2 O 5 . . . . . . . . . . |
$$ | . . . . 1 6 0 4 . . . . . . . . . . . |
$$ | . . c . a 7 8 . . . . . . . . . . . . |
$$ | . . . X . . b . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+

Click Here To Show Diagram Code

[go]$$Wm26 Takao's plan
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O O . O O O . O . . . . . . . . |
$$ | . . . , X . . X X X . . . . . , X . . |
$$ | . . X . . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . O . X . . . . . . . . . . . |
$$ | . . . , . 9 O X . , . . . . . , . . . |
$$ | . . . X 3 X 2 O 5 . . . . . . . . . . |
$$ | . . . . 1 6 0 4 . . . . . . . . . . . |
$$ | . . c . a 7 8 . . . . . . . . . . . . |
$$ | . . . X . . b . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]

So conclusion so far:
- Elf agrees with Shuko counter peep is better (easily so if black obeys)
- Elf agrees with Shuko that the end result of Morita's worry of black resistance is fine for white (but some big mistakes from both in the sequence Shuko didn't highlight)
- Elf agrees with Shuko that Takao's planned counter was bad

Pretty good marks so far. But Elf sees a better black counter that isn't mentioned in the book. The push and then connect. My explanation is that black also makes white heavy and by cutting on the outside delays that c7 weakness by starting a new fight so white is too busy (though the a-c tesuji is incoming and there's lots of violence).

$$Bcm27 Elf black best answer to counterpeep
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O O . O O O . O . . . . . . . . |
$$ | . . . , X . . X X X . . . . . , X . . |
$$ | . . X . . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . O . X . . . . . . . . . . . |
$$ | . . . , . . O X . , . . . . . , . . . |
$$ | . . . X 3 X 4 O . . . . . . . . . . . |
$$ | . . . . O 1 O . . . . . . . . . . . . |
$$ | . . b a . 2 5 7 . 9 . . . . . . . . . |
$$ | . . c X . 6 . . . . . . . . . . . . . |
$$ | . . . . . . 8 . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+

Click Here To Show Diagram Code

[go]$$Bcm27 Elf black best answer to counterpeep
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O O . O O O . O . . . . . . . . |
$$ | . . . , X . . X X X . . . . . , X . . |
$$ | . . X . . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . O . X . . . . . . . . . . . |
$$ | . . . , . . O X . , . . . . . , . . . |
$$ | . . . X 3 X 4 O . . . . . . . . . . . |
$$ | . . . . O 1 O . . . . . . . . . . . . |
$$ | . . b a . 2 5 7 . 9 . . . . . . . . . |
$$ | . . c X . 6 . . . . . . . . . . . . . |
$$ | . . . . . . 8 . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]

A quick summary of problem 40. Elf agrees with Shuko that young Kenmochi's play was bad: Shuko: "black's profit is very big ... discouraging for white to continue ... a little painful and difficult; Elf: "first move -40%, ends with white 4%". Elf thinks Shuko's proposed move is ok (some diagreement over following sequence), but another move a few % better.

Problem 42 is the third I look at and first where Elf strongly disagrees with Shuko's sequences and conclusions. Shuko says Takao's play as white was very heavy and his opponent just played obvious moves for a better result. Elf says Takao started at 35%, his first move was indeed bad (down to 22) but his opponent made a bigger mistake (unremarked by Shuko, I would have played Elf's move!) and Takao's bad result ended up good at 70%. On the other hand Shuko's only move was -17% and his mainline result of living in sente was indeed better (white 52% with where he spent his sente, 66% with Elf's) but contained indulgent reading of soft play by opponent so was really 45% says Elf. He did offer an alternative reply to his 1st move, Elf says much better, and ends with a result he sees as ok "easy for white to make sabaki" which Elf hates (white 4%, and this is with more komi than the games presumably had). The AIs are rather territorial so there could be a style difference in that humans can win with a light sabaki result giving the opp territory, whereas bot likes the cash, but a Shuko preferring a 4% result over Takao's 70% is quite a discrepancy!

[Bill Spight]

So this thread doesn't come across as a van Zeijst / Bozulich bash, . . .

I expect that the material in their shape book is standard fare, with little in the way of original composition. They may have altered the contexts of problems so as not to be accused of copying. So any criticism is not directed at them personally, but at generally accepted go "knowledge". For instance, the underneath connection appears in Sakata's Tesuji and Antisuji of Go, with a slightly different context. It is presented as a connection problem, so the hane is a failure, but it also judges the hane harshly, saying that it causes great damage to White's position. Leela Zero offers a valuable correction.

[Uberdude]

Another Shuko problem makes for an interesting "find the pro's mistakes" exercise. The problem is at move 60, but in the intro to the position Shuko picks out one black move for harsh criticism. Elf agrees Shuko's move is better (but not best, that's one puzzlingly similar to the bad move), but picks out 1 white move as being terrible (-26%), can you find it? Playing through the game it did seem odd to me and I expected the Elf move. Elf also highlights another large (10%) white mistake but that one's rather more subtle but made sense to me once I'd played around with some variations.

So whilst Elf agrees Takao's 60 was bad and likes Shuko's suggestion (though expected variation different), it's saying he's focusing on the wrong part of the game as black was winning with 99.6% just a few moves earlier.

(;GM[1]FF[4]CA[UTF-8]AP[WebGoBoard:0.10.11]ST[2]SZ[19]KM[6.5]HA[0]PB[Akiyama Jiro]PW[Takao Shinji];B[pd];W[dd];B[cp];W[pp];B[eq];W[cg];B[qn];W[nq];B[rp];W[nc];B[lc];W[qq];B[nd];W[ql];B[po];W[qi];B[op];W[oq];B[qp];W[pq];B[qg];W[oc];B[od];W[qc];B[pc];W[pb];B[ob];W[nb];B[qb];W[oa];B[rc];W[mc];B[lb];W[md];B[fc];W[mf];B[id];W[qf];B[pf];W[rf];B[qd];W[rg];B[cc];W[cd];B[dc];W[ed];B[ec];W[dl];B[ol];W[pm];B[rl];W[rk];B[om];W[rm];B[nn];W[kd];B[jc];W[kq];B[dj])

(Leela Zero #157 agrees the terrible move was bad (just 7% in milder LZ land) and the other white mistake, but thinks Takao's 60 was fine, as is Shuko's alternative.)

[Bill Spight]

Another Shuko problem makes for an interesting "find the pro's mistakes" exercise.

Just think. In ten years we can have "find the bot's mistakes" exercises.

[Uberdude]

Just think. In ten years we can have "find the bot's mistakes" exercises.

That's easy, in one of the Making Good Shape problems Elf got the tesuji right but then afterwards wanted (for several thousand playouts) to play out a ladder in which one of the initial surrounding stones was in atari.

[John Fairbairn]

Going back to the good shape theme of the thread, what do you make of this?

(;AB[pc][od][pe][qd]AW[dd][dp][pp]LB[pd:A]SZ[19])

LZ on my setup starts with a White winrate of 53.6% (presumably that measures the komi as being fractionally too high).

I forced the above position, playing White 1 on A. The winrate changed to 56.6%. This was for a ponnuki based on 3-4.

When I did similar things with ponnukis based on 4-4, 4-5, 5-5 and 3-5, the winrates changed to 53.0, 54.3, 53.8 and 53.0 respectively.

I'm not sure that the difference in each winrate means much here, although I was surprised that the 4-4 based ponnuki, being nearer the centre and so (I assume*) more influential seemed the worst version. However, what I really wanted to check was the accuracy of the proverb that a ponnuki capture is worth 30 points. If you count each surviving White stone as 10 points, the proverb seems to stand up well, but perhaps it could be more accurately re-cast as either "worth three enemy plays" or "worth 30-40 points.

But the proverb that the turtle-shell capture is worth 60 points seems way off. To give just an example starting with 4-4, as below, White's winrate shot up to 64.2%.

(;AB[pc][od][qd][oe][pf][qe]AW[dd][dp][pp][jj]TR[jj]LB[qn:A][jc:B]SZ[19])

I initially tried the centre point as the extra White move to balance the number of stones played. I assumed* that that was the best way to negate Black's influence. But LZ preferred A or B (both around 62%).

*Twice I have mentioned assumptions I made and in both cases was foolish. On reflection, seeing that LZ apparently preferred the sides, I recalled that Go Seigen made the point that what we might call the centre-sides are the most neglected parts of the board. It was that remark that led me to invent the Go Seigen Group as a joke (allied to T Mark's joke that White 8 is always wrong, according to Go Seigen), but it turned out to be a reasonable insight into the game. I'm now thinking that Go was even more right, and yet another example of how he was the Sai of the past to today's bots.

It's interesting, too, that in uberdude's investigion above, AI seems to be confirming we are right to put Fujisawa Hideyuki on a pedestal as another all-time great. Perhaps our judgements about the relative strengths of players are sound.

[Calvin Clark]

My policy network for this position (I expect a is the book answer, but I'd like to get b in sente first if I can). h is for giggles.

$$Bc Problem 4. Black to play and expand moyo.
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . e . . . . O . . . . O b . . . . |
$$ | . . O d c . . . h , . . . . . X . . . |
$$ | . . . . . . . . . . . . . W . . . . . |
$$ | . . . . . . . . . . . . . i . X . . . |
$$ | . . . . . . . . . . . . . a . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . X . . . |
$$ | . . . f . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . X . . . . . . |
$$ | . . . O . X . . . , . . . . X X X . . |
$$ | . . . g . . . . . . . X . O . O O . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------

Click Here To Show Diagram Code

[go]$$Bc Problem 4. Black to play and expand moyo.
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . e . . . . O . . . . O b . . . . |
$$ | . . O d c . . . h , . . . . . X . . . |
$$ | . . . . . . . . . . . . . W . . . . . |
$$ | . . . . . . . . . . . . . i . X . . . |
$$ | . . . . . . . . . . . . . a . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . X . . . |
$$ | . . . f . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . X . . . . . . |
$$ | . . . O . X . . . , . . . . X X X . . |
$$ | . . . g . . . . . . . X . O . O O . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

I just checked Elf v1, and it likes b and f most. f is only available because white made a one-space jump there instead of 2 space, which Elf would prefer a bit. With this kind of Takemiya moyo building you sometimes see black making the 2-space high approach and then 2-space jump in that corner. But most interesting thing for me was what Elf preferred for white's last move instead of the marked jump: p12 reduction. That kind of move is rarely on my radar but now that I think about it I recall Matthew Macfadyen 6d suggesting such ideas in similar positions.

What surprised me a bit is LZ and ELF responses to the "correct" move.

LZ:

LZ.png (1.21 MiB) Viewed 14753 times

It's a vital point, for sure, but it seems too early, especially if LZ evaluates white as being ahead.

ELFV1:

ElfV1.png (1.2 MiB) Viewed 14753 times

ELFV1 agrees, but also has a more negative view of the correct move.

[Bill Spight]

My policy network for this position (I expect a is the book answer, but I'd like to get b in sente first if I can). h is for giggles.

$$Bc Problem 4. Black to play and expand moyo.
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . e . . . . O . . . . O b . . . . |
$$ | . . O d c . . . h , . . . . . X . . . |
$$ | . . . . . . . . . . . . . W . . . . . |
$$ | . . . . . . . . . . . . . i . X . . . |
$$ | . . . . . . . . . . . . . a . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . X . . . |
$$ | . . . f . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . X . . . . . . |
$$ | . . . O . X . . . , . . . . X X X . . |
$$ | . . . g . . . . . . . X . O . O O . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------

Click Here To Show Diagram Code

[go]$$Bc Problem 4. Black to play and expand moyo.
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . e . . . . O . . . . O b . . . . |
$$ | . . O d c . . . h , . . . . . X . . . |
$$ | . . . . . . . . . . . . . W . . . . . |
$$ | . . . . . . . . . . . . . i . X . . . |
$$ | . . . . . . . . . . . . . a . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . X . . . |
$$ | . . . f . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . O . X . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . X . . . . . . |
$$ | . . . O . X . . . , . . . . X X X . . |
$$ | . . . g . . . . . . . X . O . O O . . |
$$ | . . . . . . . . . . . . . O . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

I just checked Elf v1, and it likes b and f most. f is only available because white made a one-space jump there instead of 2 space, which Elf would prefer a bit. With this kind of Takemiya moyo building you sometimes see black making the 2-space high approach and then 2-space jump in that corner. But most interesting thing for me was what Elf preferred for white's last move instead of the marked jump: p12 reduction. That kind of move is rarely on my radar but now that I think about it I recall Matthew Macfadyen 6d suggesting such ideas in similar positions.

What surprised me a bit is LZ and ELF responses to the "correct" move.

LZ:

LZ.png

It's a vital point, for sure, but it seems too early, especially if LZ evaluates white as being ahead.

ELFV1:

ElfV1.png

ELFV1 agrees, but also has a more negative view of the correct move.

Wow! It's almost as if Black's book play weren't there.

[Bill Spight]

Going back to the good shape theme of the thread, what do you make of this?

(;AB[pc][od][pe][qd]AW[dd][dp][pp]LB[pd:A]SZ[19])

LZ on my setup starts with a White winrate of 53.6% (presumably that measures the komi as being fractionally too high).

I forced the above position, playing White 1 on A. The winrate changed to 56.6%. This was for a ponnuki based on 3-4.

That more or less fits with my estimate that Black has lost around 6 pts. Close to equality at the beginning of the game, that means that each Leela Zero percentage point roughly corresponds to 2 pts. of territory. That is consistent with 40 year old pro statistics.

However, what I really wanted to check was the accuracy of the proverb that a ponnuki capture is worth 30 points. If you count each surviving White stone as 10 points, the proverb seems to stand up well, but perhaps it could be more accurately re-cast as either "worth three enemy plays" or "worth 30-40 points.

Right. The 30 pt. estimate proved to be too low, based upon the fact that a 5 pt. komi is too small. But it's still worth less than 3 early enemy plays, by overconcentration. My estimate is around 36 pts. of territory.

But the proverb that the turtle-shell capture is worth 60 points seems way off. To give just an example starting with 4-4, as below, White's winrate shot up to 64.2%.

The turtle shell is way overconcentrated. I estimate it at around 43 pts. of territory. If I'm right, the next 7 pts. of territory are worth around 8 Leela Zero percentage pts.

Edit: When I say that the ponnuki and turtle shell are over concentrated, I mean by themselves, not in the tactical context in which they are likely to arise.