Regarding "starting over", I recall that when, as a teenager, Michael Redmond went to Japan to become a live-in deshi he was a strong amateur 5-dan and he was told he had to relearn his joseki. In that context joseki did not mean corner sequence but rather his view in general of the standard way to play. Certainly douible digit kyu level players have to make a change in how they think in order to get to single digit level, again as a dan player, etc.John Fairbairn wrote: ...told to forget everything you learned in junior school and start again. Then when you go to university you are told to forget everything you learned in high school and start again.
I have since learned that that paradigm applies in other subjects. Language is not one of them, but piano technique may be one, and maybe art. Perhaps go is? (But of course I accept that somewhere in that mix, so-called experts can also just be plain wrong - just like expert bots with ladders)
Otake's masterpiece
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gowan
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Re: Otake's masterpiece
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Bill Spight
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Re: Otake's masterpiece
Let me use the first moves of this game and the Elf commentary to explore some of the questions raised about go knowledge, bot choices, and making improvement. One advantage of the Elf commentaries is that they are based on a large number of rollouts, many more than we ordinarily might have the time to wait for.
First, let me start with
. It is certainly playable, but it is nearly off of Elf's radar, with only 8 rollouts. It loses 1% in winrate to Elf's first choice, a, which gets 40k rollouts. Elf does not even show its second choice, which means that it got fewer than 1500 rollouts. My guess is that it is 
. Looking at this and other games, it appears that Elf has a small but decided preference for 4-4 points, but that does not mean that other corner plays are bad. The margin of error matters, whatever it is. 
is no surprise to those who study pro games or have read Kajiwara's book, The Direction of Play. bears a good relationship, we are told, to 
. How bad can it be? Well, says Elf, it gets 0 rollouts and loses 6% to the nirensei at 5 (25.8k rollouts), which makes it a minor error in my book. It is hardly fatal, OC. (Elf and other bots do not seem to care about the human concept of direction of play. Until, perhaps, a little later in the game.) After the White nirensei, Black encloses the top right corner at c. That enclosure is AI knowledge. It was not previously unknown, OC, but Black usually played more solid enclosures; it was White, usually playing catch-up, who played the thin enclosures. Elf's second choice for is b.
Otake occupied the last open corner with. This is in line with my proposed bit of modern go knowledge, based upon Elf's choices, which is that playing in the last open corner is a kind of last play. It is not always correct, OC, but it is a good idea. In this case Elf prefers the play in the next diagram by 2½%.
Before occupying the open corner, Elf prefers to take profit in the top right corner with sente. The usual joseki is for Black to extend to a, but that would allow White to take the last open corner.
When I was learning go, leaving the attachment,
, was generally frowned upon. After 
White usually extended to 
and Black crawled on the second line. But the bots often like the two step hane at 
. This shape occurs 24 times in Waltheri ( http://ps.waltheri.net ), 9 times in the AI era.
BTW, some of you may be wondering how you can get a reliable winrate estimate from 0 rollouts
, or even 8. Well, you can't. What Elf does is to inherit the estimate from Elf's top choice for the next play. Thus, got its winrate estimate from the White nirensei in the bottom left corner, and got its from Elf's underneath attachment in the top right corner. Elf does this for any play with fewer than 500 rollouts. By contrast, how many winrates have you seen based upon 100 rollouts or less? 
This is as far as I am going to go, now. If was a minor error, how bad is 
? You might well ask. It loses 7½% to the outside attachment at a, says Elf, another minor error. See, we figured out that was problematic, based upon the fact that was.
What about
? Here is where the human concept of the direction of play becomes relevant, IMO. If bears a good relation to , how much better will the relationship be between and the stronger White position after White replies? It seems to me that direction of play points to playing in the bottom right corner. Elf prefers the bottom attachment there by 4%, which puts in the top right into questionable territory. It may not be a mistake, but it might be.
I don't know why is high, but look at , an unusual joseki for the top right corner. Again, I think that direction of play is a factor. The bots have taught us that the "standard" extension from the bottom right stones can wait, as a rule, but surely works with - . It seems that Elf thinks that the attachment at a or the keima at b are each a little too far away.
and 
take profit in the corner, no surprise there, and then 
approaches the top left corner from the top side, something that may go against the idea of playing from the wide side, but plainly obstructing White's development on the top side. 
refrains from a pincer, something that we learned from AlphaGo. Next, 
enters the right side with a pincer and 
jumps into the center, something we also have learned to expect from AI.
In case we didn't know, is another minor error, losing 7% to the solid connection at a. gets 0 rollouts, while a gets 91.4k rollouts. Elf really likes a. Even though White has made only minor errors, he has lost 15% in only 5 moves. It all adds up, as Kirby has pointed out. Keep in mind that all of White's plays so far have conformed to the collective go knowledge of the time, of which White was a master.
One advantage of the Elf commentaries is that they are based on a large number of rollouts, many more than we ordinarily might have the time to wait for.First, let me start with
. It is certainly playable, but it is nearly off of Elf's radar, with only 8 rollouts. It loses 1% in winrate to Elf's first choice, a, which gets 40k rollouts. Elf does not even show its second choice, which means that it got fewer than 1500 rollouts. My guess is that it is . Looking at this and other games, it appears that Elf has a small but decided preference for 4-4 points, but that does not mean that other corner plays are bad. The margin of error matters, whatever it is. is no surprise to those who study pro games or have read Kajiwara's book, The Direction of Play. bears a good relationship, we are told, to . How bad can it be? Well, says Elf, it gets 0 rollouts and loses 6% to the nirensei at 5 (25.8k rollouts), which makes it a minor error in my book. It is hardly fatal, OC. (Elf and other bots do not seem to care about the human concept of direction of play. Until, perhaps, a little later in the game.) After the White nirensei, Black encloses the top right corner at c. That enclosure is AI knowledge. It was not previously unknown, OC, but Black usually played more solid enclosures; it was White, usually playing catch-up, who played the thin enclosures. Elf's second choice for is b.Otake occupied the last open corner with
. This is in line with my proposed bit of modern go knowledge, based upon Elf's choices, which is that playing in the last open corner is a kind of last play. It is not always correct, OC, but it is a good idea. In this case Elf prefers the play in the next diagram by 2½%.Before occupying the open corner, Elf prefers to take profit in the top right corner with sente. The usual joseki is for Black to extend to a, but that would allow White to take the last open corner.
When I was learning go, leaving the attachment,
, was generally frowned upon. After White usually extended to and Black crawled on the second line. But the bots often like the two step hane at . This shape occurs 24 times in Waltheri ( http://ps.waltheri.net ), 9 times in the AI era.BTW, some of you may be wondering how you can get a reliable winrate estimate from 0 rollouts
, or even 8. Well, you can't. What Elf does is to inherit the estimate from Elf's top choice for the next play. Thus, got its winrate estimate from the White nirensei in the bottom left corner, and got its from Elf's underneath attachment in the top right corner. Elf does this for any play with fewer than 500 rollouts. By contrast, how many winrates have you seen based upon 100 rollouts or less? This is as far as I am going to go, now. If
was a minor error, how bad is ? You might well ask. It loses 7½% to the outside attachment at a, says Elf, another minor error. See, we figured out that was problematic, based upon the fact that was. What about
? Here is where the human concept of the direction of play becomes relevant, IMO. If bears a good relation to , how much better will the relationship be between and the stronger White position after White replies? It seems to me that direction of play points to playing in the bottom right corner. Elf prefers the bottom attachment there by 4%, which puts in the top right into questionable territory. It may not be a mistake, but it might be. I don't know why
is high, but look at , an unusual joseki for the top right corner. Again, I think that direction of play is a factor. The bots have taught us that the "standard" extension from the bottom right stones can wait, as a rule, but surely works with - . It seems that Elf thinks that the attachment at a or the keima at b are each a little too far away. and take profit in the corner, no surprise there, and then approaches the top left corner from the top side, something that may go against the idea of playing from the wide side, but plainly obstructing White's development on the top side. refrains from a pincer, something that we learned from AlphaGo. Next, enters the right side with a pincer and jumps into the center, something we also have learned to expect from AI.In case we didn't know,
is another minor error, losing 7% to the solid connection at a. gets 0 rollouts, while a gets 91.4k rollouts. Elf really likes a. Even though White has made only minor errors, he has lost 15% in only 5 moves. It all adds up, as Kirby has pointed out. Keep in mind that all of White's plays so far have conformed to the collective go knowledge of the time, of which White was a master.
Last edited by Bill Spight on Fri Jan 17, 2020 12:07 pm, edited 3 times in total.
The Adkins Principle:
At some point, doesn't thinking have to go on?
— Winona Adkins
Visualize whirled peas.
Everything with love. Stay safe.
At some point, doesn't thinking have to go on?
— Winona Adkins
Visualize whirled peas.
Everything with love. Stay safe.
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Uberdude
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Re: Otake's masterpiece
If I can paraphrase John's hypothesis which I think Bill disagreed with, as "pro's aren't much weaker than bots, if only they didn't make silly mistakes below their true level", then I don't agree either. I think bots are quite a bit stronger (for fairness we should also allow them enough playouts to not make silly mistakes below their true level). I'd finger-in-the-air say it's similar saying 5 kyus are as strong as 4 dans if only they didn't make silly mistakes. And I say this as a 3 dan who when not making silly mistakes beat a 3p,Bill Spight wrote:Sadly, no.John Fairbairn wrote:Do others have similar feelings?More below.
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ez4u
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Re: Otake's masterpiece
@'dude Just for fun, how about posting an AI analysis of your game with breakfast so we can see who had the silly mistakes and where?Uberdude wrote:
...And I say this as a 3 dan who when not making silly mistakes beat a 3p,
Dave Sigaty
"Short-lived are both the praiser and the praised, and rememberer and the remembered..."
- Marcus Aurelius; Meditations, VIII 21
"Short-lived are both the praiser and the praised, and rememberer and the remembered..."
- Marcus Aurelius; Meditations, VIII 21
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xela
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Re: Otake's masterpiece
Yes, the "forget everything you knew before" paradigm is common in high-level music teaching (although it's thankfully becoming rarer these days). Specifically, it's done as a type of initiation, for social not pedagogical reasons (although I think most of the culprits don't consciously frame it that way, they're just doing as they were done unto). This rite of passage servers to boost the teacher's mystique, as well as weeding out students who aren't really serious. I think this may be a cultural universal. Not just for European teachers of classical music, but think of the stereotypical Zen monk who spends five years sweeping floors and carrying water before getting to "the good stuff'.John Fairbairn wrote:My friend explained that when you study chemistry at high school level you are - with not too much exaggeration - told to forget everything you learned in junior school and start again. Then when you go to university you are told to forget everything you learned in high school and start again.
I have since learned that that paradigm applies in other subjects. Language is not one of them, but piano technique may be one, and maybe art. Perhaps go is? (But of course I accept that somewhere in that mix, so-called experts can also just be plain wrong - just like expert bots with ladders :))
Piano teacher Abby Whiteside wrote an inspiring but dangerous book called "Mastering the Chopin Etudes". She rails against Czerny studies: a large collection of exercises that you can think of as the pianist's equivalent of a big tsumego dictionary. They're frequently parodied for their dryness, although they're actually a bit better than their reputation. Whiteside advocates going directly to Chopin's studies (or etudes if you prefer the French) without wasting your time on Czerny. The Chopin pieces are exercises in a sense, but of a high artistic standard and challenging even for professionals -- think of a pianist's Igo Hatsuyoron. So Whiteside has some good insights about posture and engaging your shoulders and spine, not just your fingers (whole-board thinking!), but she says that she "wasted" years on Czerny, until suddenly she had her own special insights and could play Chopin without effort.
To read her books, you would expect that her students would have taken over the (piano) world by now. But actually, the people who've literally tried "forget everything you knew before", or not even wasted the time building those foundations, haven't been successful. Maybe Whiteside's ability to play Chopin isn't due to her special insights, but actually due to the years of hard work she put in on Czerny first? And possibly (I'm guessing here because I've never met any of these pianists in person, or even heard them play) her teacher's mystique has done some harm to her students.
Back to university study. Certainly first year mathematics could be described as "reteach all the calculus you learned in high school, but do it properly this time". But by doing the high school version first, you've acquired a certain fluency of calculation, and familiarity with the language, that will help you a lot when you "go back" and look more closely at the foundations. None of my teachers told me to forget things. And people who came in to university via alternative pathways, without high school maths, had to work very hard to catch up with those of us who had "learned it wrong" the first time.
Perhaps Michael Redmond's "learn joseki and then 'forget' them all" left some traces in his brain which put him ahead of people who had never even tried to learn joseki?
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Cassandra
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Re: Otake's masterpiece
"Forget everything you know" must not be taken literally.xela wrote:Perhaps Michael Redmond's "learn joseki and then 'forget' them all" left some traces in his brain which put him ahead of people who had never even tried to learn joseki?
Probably this advice came from martial arts training (or from classic legends about it).
Its deeper meaning is to only act unconsciously (after more than sufficient training). As a matter of course, no samurai has "forgotten" his sword fighting techniques, so that he can no longer use them successfully. But he is not hindered in his actions by the need to "remember" these techniques conciously, which might take a bit too long to survive the fight.
The really most difficult Go problem ever: https://igohatsuyoron120.de/index.htm
Igo Hatsuyōron #120 (really solved by KataGo)
Igo Hatsuyōron #120 (really solved by KataGo)
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SoDesuNe
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Re: Otake's masterpiece
To add to this: Studies repeatedly showed that strength difference between chess players can be explained by their subconscious pattern recognition (chunking). Stronger players "see" the good/best moves faster (less candidate moves).Cassandra wrote:Its deeper meaning is to only act unconsciously (after more than sufficient training). As a matter of course, no samurai has "forgotten" his sword fighting techniques, so that he can no longer use them successfully. But he is not hindered in his actions by the need to "remember" these techniques conciously, which might take a bit too long to survive the fight.
Furthermore in tactical positions stronger players search only 3.6 moves deep. Weaker players search 5.1 moves deep in the same positions. Both on average.
So, yeah: Subconsciousness ftw : )
Source: https://www.chess.com/article/view/the- ... y-of-chess
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kvasir
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Re: Otake's masterpiece
On the assumption that this topic/thread is about the game and not the meta discussion above I want to add something about this game. I'm very interested in Takagawa's predicament. Playing a game and having KataGo tell you that you never really had a chance is very relatable
I only browsed through it before I started KataGo and it could be hard for me to separate my initial observations from what I observed later, however, my initial observations were something akin to the following:
1. There isn’t anything wrong with the first 20-30 moves per se. Which I’m calling the “early” opening. The most common style of the time seems to have been to make some rather mysterious moves in the opening, that I doubt anyone though were the only move except that-one-guy
2. Somehow, black quickly became very thick after the early opening. White was making some unusual moves that let black fix his shapes.
3. The game was probably rather close for the most part but there was an imbalance. The imbalance is that if black was behind he could try to shake the game but if white was behind it was not clear what to do about it except hope for a really clumsy mistake.
This is the position after the “early” opening.
This is the position when I though white has allowed black to get thick or have strong shapes everywhere.
While I ran KataGo I read the various comments in the thread provided and realized that they didn’t closely match what I was seeing from KataGo. I also checked some databases and found that the first few moves in the opening have been played often enough that I’d expect it to have been studied by pros.
At some point I realized that the game information gives komi of 5.0, which is 1.5 less than is considered fair. That means white should be at a disadvantage from the start.
After analyzing with KataGo I had the following observations:
1. The first first diagram above (move 23) is evaluated as B+2.0 (komi 5.0 and 100k po) which is expected. The second diagram (move 51) is b+6.0 points and that is basically a difference of half a handicap stone.
2. White appears to have made a clumsy mistake in the opening on move 48. I wonder if it is something mentioned in period game reviews.
Let me try to explain.
3 The game is bit like a model for when you are behind but don't know what to do about it. I don't know if it can be said to be clear that white was behind but it did turn out that way. White didn't play a poor middle game but probably had to try something provocative early and missed his chance. KataGo won't necessarily give a clear indication of how to create chances but you can use it to get ideas.
4 How to avoid making the opponent strong is a more practical lesson. Something to avoid even if it might be recommended by KataGo. It appears hard to get good help with this from KataGo who will make the opponent strong if it gives a small lead and sometimes when needed it will still find some very special moves that demonstrate that there can be some weakness.
This was a great game to look at even though it sounded almost like a walkover when I started reading the thread
Maybe there are some faults with my observations, don't mind that 
I only browsed through it before I started KataGo and it could be hard for me to separate my initial observations from what I observed later, however, my initial observations were something akin to the following:
1. There isn’t anything wrong with the first 20-30 moves per se. Which I’m calling the “early” opening. The most common style of the time seems to have been to make some rather mysterious moves in the opening, that I doubt anyone though were the only move except that-one-guy
2. Somehow, black quickly became very thick after the early opening. White was making some unusual moves that let black fix his shapes.
3. The game was probably rather close for the most part but there was an imbalance. The imbalance is that if black was behind he could try to shake the game but if white was behind it was not clear what to do about it except hope for a really clumsy mistake.
This is the position after the “early” opening.
This is the position when I though white has allowed black to get thick or have strong shapes everywhere.
While I ran KataGo I read the various comments in the thread provided and realized that they didn’t closely match what I was seeing from KataGo. I also checked some databases and found that the first few moves in the opening have been played often enough that I’d expect it to have been studied by pros.
At some point I realized that the game information gives komi of 5.0, which is 1.5 less than is considered fair. That means white should be at a disadvantage from the start.
After analyzing with KataGo I had the following observations:
1. The first first diagram above (move 23) is evaluated as B+2.0 (komi 5.0 and 100k po) which is expected. The second diagram (move 51) is b+6.0 points and that is basically a difference of half a handicap stone.
2. White appears to have made a clumsy mistake in the opening on move 48. I wonder if it is something mentioned in period game reviews.
Let me try to explain.
4 How to avoid making the opponent strong is a more practical lesson. Something to avoid even if it might be recommended by KataGo. It appears hard to get good help with this from KataGo who will make the opponent strong if it gives a small lead and sometimes when needed it will still find some very special moves that demonstrate that there can be some weakness.
This was a great game to look at even though it sounded almost like a walkover when I started reading the thread
Maybe there are some faults with my observations, don't mind that -
John Fairbairn
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Re: Otake's masterpiece
One unattributed review said that White J17 was more usual for 14. Black made a lot of profit with 19. White 20 and 22 embarked on a big moyo strategy. Black 27 and 29 were a probe. If Black answers White 34 at H4, White jumps to 35. The cap at Black 34 was kiai. For the sagari of White 44, cutting at 48 is better timing; then if Black 51 there is bad aji. After 49, Black's has a lot of territory. If White 50 at K2, Black H1, White L3, then Black gets to push at 50. White 52 should be at G13 to attack on the upper side. For Black 57, G13 is correct: he cannot be satisfied to let White hit the vital point at 58. White 66 could also have been at 75, then Black E11, White F13. White 72 was a mistake. He had to push in at 75, then Black E11, White H10, to take away Black's eyes. The capture with Black 73 and 75 makes the big group safe. After this, Black had a lead on the balance of territories and so could wrap the game up with boundary plays.White appears to have made a clumsy mistake in the opening on move 48. I wonder if it is something mentioned in period game reviews.
Pedantic point: the komi was "5 + White wins jigo," so 5.5 in effect.At some point I realized that the game information gives komi of 5.0, which is 1.5 less than is considered fair.
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kvasir
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Re: Otake's masterpiece
The comments by the reviewer are reasonable enough. To me the first part is like the narration over some documentary movie.John Fairbairn wrote:One unattributed review said that White J17 was more usual for 14. Black made a lot of profit with 19. White 20 and 22 embarked on a big moyo strategy. Black 27 and 29 were a probe.
I guess the "more usual" move is the extension, the orientation of the coordinates is different.
I think this means that white can play a good enough move on the bottom if black simply defends on the top and it is not the exact move that is important. It is a reasonable explanation, defending looks to me like something for a handicap game. Maybe 'kiai' was the normal level of active play for the time?John Fairbairn wrote:If Black answers White 34 at H4, White jumps to 35. The cap at Black 34 was kiai.
Now I get a feeling that I have seen the comments before, maybe repackaged. It is also interesting because KataGo doesn't like the good timing move. It does set things in motion, it is the right time for that, but KataGo sort of refutes the move.John Fairbairn wrote:For the sagari of White 44, cutting at 48 is better timing; then if Black 51 there is bad aji.
Even though
let's white's stones settle black nevertheless appears to take good advantage of white's thinness. Black KataGo will also take control of the flow of the game for a good while in a position that was already advantageous. I guess there is no telling if a human opponent like Otake would play this way and practically, when not playing a computer, someone might just prefer the early cash for white.
I wasn't going to rate every observation by the unattributed reviewer but I think it reasonable to call this a good timing, despite KataGo's -1.5 points reaction (the whole sequence starting on move 40 is -3.2 points). I'm not sure what the reviewer means by "bad aji" as black's next move would be very big and white therefore needs to play first in this area anyway.
If black had played the other atari in the corner then the good timing move is approved. In this case white's outside is improved.
I think that is as in the following diagram.John Fairbairn wrote:After 49, Black's has a lot of territory. If White 50 at K2, Black H1, White L3, then Black gets to push at 50. White 52 should be at G13 to attack on the upper side.
Sounds like pro advice. I can think of waiting in a line at EGC for a pro to review my own game and then they come to a situation like this and say "Vital point!", "Attack first!", "Very good!", and "Oh no!" and "Maybe OK" when they see the game move. KataGo seems to think it is not forceful.John Fairbairn wrote:White 52 should be at G13 to attack on the upper side.
At first KataGo indicated many acceptable moves in the game position but after checking them one by one something that is certainly similar to the game stands out. The difference is that white takes an important forcing move (blocks or slows down black's access to the center, or just prevents a good black move?) and then goes directly for
. Leaving out the game move is the principle of playing C instead of A-B-C. Black's corner is softer when the A-B hasn't been played. The need for
might not have been on white's radar and he is otherwise basically handling the situation similarly to what KataGo suggests. The difference is rather small in terms of evaluation. Maybe this is why I bother replying with all the diagrams. The suggestion is to cut but white invests too much in this attack. Normally the good way to attack is to take some profit first. The opposite is to trade something for the attack, sometimes referred to as "bribing your opponent", that way you can struggle to get back what you paid up front. KataGo says black is just fine but I think the point is that white isn't fine. Maybe the reviewer suggests this for the reader to think about.John Fairbairn wrote: White 66 could also have been at 75, then Black E11, White F13.
That is something I noticed too and it is very instructive: Don't just let the opponent's groups become safe. The variation or the timing is not perfect from KataGo's perspective but instructive. A move earlier, which is move 70, it suggests something it considers slightly better. I think it wants to try to hang in there and keep the game close on points, which is usually a good idea. It suggests the following way.John Fairbairn wrote:White 72 was a mistake. He had to push in at 75, then Black E11, White H10, to take away Black's eyes. The capture with Black 73 and 75 makes the big group safe. After this, Black had a lead on the balance of territories and so could wrap the game up with boundary plays.
White first strengthens the side with
and finishes by enclosing one side of the center with . Black is practically alive and the evaluation is B+5.2. The difference to the reviewers variation (B+7.3) isn't much.I'm confused how KataGo will keep this position so close. The reviewer suggestion might be better for myself. I think I understand that KataGo wants to avoid giving something up for keeping black from being too easily alive and it suggests a way that has white take some profit first but black is practically alive anyway (as far as I can tell).
Maybe those are two different approaches to playing when slightly behind. Reviewer logically (because that is what you do) wants to prevent black from having a completely safe group since safety for black leads to an endgame-like situation, KataGo wants to keep the game as close as possibly and force the black group to defend later and is very confident of its endgame.