Tewari analysis

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ez4u
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Re: Tewari analysis

Post by ez4u »

John Fairbairn wrote:
You can be pedantic and insist that this is only about 'joseki' (although I think you must have to close your eyes for some of Kobayashi's diagrams in order to maintain your theory).
I can understand the "PARIS IN THE THE SPRING" kind of misread, but for the life of me I cannot understand the high frequency of misreads in this forum. Is it wilful?

I said "mainly joseki", Cassandra said "mainly", yet you change it to "only" joseki. On top of that, the Kobayashi quoted is also mainly about joseki, as observed by Cassandra, and that is implicit in Kobayashi's words cited ("Tewari plays a role ALSO in fuseki", i.e. joseki gets the main mention).

But this problem is widespread. I have no doubt I do it myself.
In post #3 you wrote [emphasis added]
John Fairbairn wrote:
I wanna know how one would analyze this Fuseki with Tewari. Can one give a step-by-step description? I still dunno how exactly it works.
That's probably because tewari (dissection of moves, aka ishiwari) is not really intended for fuseki. It's mainly a joseki tool.

There are two separate modes of analysis: (1) try changing the move order to see whether you would have ended up making a different choice if you have had that freedom in actual play - if so, that hints at inefficiency in your actual choice; (2) remove an equal number of surplus stones for each side and see whether, after that, one side has any "silly" stones still there.

This is the Japanese version. There are snake-oil vendors of other versions.
I believe that the main implication here for most readers (if not the author) is that the failure to understand is due to the inapplicability of tewari to fuseki. To complain about people missing the "mainly" in your post is close to misreading your own words IMHO.

In post # 5 Cassandra wrote [emphasis added]
Cassandra wrote:
RobertJasiek wrote:Also other forms of tewari are meaningful and useful (although hardly for the OP position) and therefore no "snake-oil".
Better use another technical term then ?

As John pointed out, 手割り (tewari) is for usage in 定石 (jôseki) only.
Where is the "mainly" here? Perhaps you would like to complain about Cassandra misreading your earlier post? :)

In post # 7 Cassandra wrote [emphasis added]
Cassandra wrote:
RobertJasiek wrote:
Cassandra wrote:(tewari) is for usage in 定石 (jôseki) only.
There is no need to restrict it to joseki.
This might be true for the underlying technical concept of "reverse engineering".

However, in every Japanese Dictionary of Go terms that I own, the term "手割り" (TEWARI) is strictly restricted to JÔSEKI. Other used cases are NOT mentioned at all.

I would like to suggest an application of what King Philip of Macedonia once told his heir:

"My son, ask for thyself another Kingdom, for what which I leave is too small for thee."
Where is the "mainly" here?

(For those who value dictionary definitions over the writings of someone like Kobayashi Satoru) Here is the text of the current (electronic) version of the Nihon Kiin's small dictionary (用語小事典). Primary reference to joseki? Yes. Restricted to joseki? No.
Tewari def nihon kiin small dic.jpg
Tewari def nihon kiin small dic.jpg (86.38 KiB) Viewed 6412 times
Thinking that tewari is somehow restricted to joseki or inappropriate/unusable for fuseki is simply wrong IMHO. But if that floats your boat, good luck with it!
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Re: Tewari analysis

Post by Pippen »

Bill Spight wrote: Why rely upon authority? :)
Because 1. I am a German and 2. it's easier to just follow :). But seriously: I think an extension from a strong corner is at least as valueable than a loose kakari or shimari in the lower area. I may put this question to the german board for there are some EGF-6d's. Remember: Bill's point against my tewari-algorithm is only successful if his second board example is judged BETTER than the first, equality is not enough.
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Re: Tewari analysis

Post by Bantari »

Bill Spight wrote:You need to develop your own judgement. Why rely upon authority? :)
I am not sure if you are joking here or not. In ase you are not, it seems to me a bit ironic.
Here we have a guy who did make his own mind (right or wrong) and a bunch of people argue that he should instead listen to either a dictionary or a stronger player. Then when he suggests to seek stronger players' input, he is told he should make his own mind instead. I don't get it.

I think the only important thing here is: is the application of tewri (as a general method) proper or not. Lets pus aside the whole "joseki" issue - sometimes even pros are not sure what really is joseki and what is not, and they seem to change their mind from time to time. Or so it seems.

PS>
Mind bender, for those claiming tewari is only for joseki analysis:
If we apply tewari analysis to a joseki sequence, and thus prove that it is not a joseki, was the application of tewari appropriate? And if it was not (since it only applies to a joseki) - was our proof correct? Maybe the sequence is a joseki after all? But then the tewari was correct and it is not jokes... but then then tewari was not correct and it might still be jokes... but then...

Personally, I think that of a tewari method helps you make better moves, go ahead and apply it, even in yose if you wish. Why not?
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Re: Tewari analysis

Post by Cassandra »

Pippen wrote: Of course the first one, in the second White looks worse or at least not better. Because there White is thin everywhere, while Black has a bullstrong corner with a double wing. Let's see what some really strong players (4d+ KGS, 8d+ Tygem) would prefer. Maybe someone can check Zen or CS for that.
CrasyStone (2012) prefers version two, but would have never played Black 5, which reduced Black's winning probability a lot.

Therefore, you started your analysis too late. Your reference position can include the first four moves only.
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Re: Tewari analysis

Post by Pippen »

Cassandra wrote:
CrasyStone (2012) prefers version two, but would have never played Black 5, which reduced Black's winning probability a lot.
So as Black CS would prefer the second version of the lower two diagrams?

That'd be sufficient, because it would show that the first version is better for White, and since this version is the one of the re-shuffled board of my example tewari analysis one can say that no White move was suspicious. And since Black's move 5 looks bad in the re-shuffled board one could conclude out of my algorith that 7 in the original board was wrong. My tewari-algorithm would work. Of course that would be just one example, and CS 2012 might not be stronger than 1k, so still kind of hanging in the air.
Bill Spight wrote:
Click Here To Show Diagram Code
[go]$$B White approaches the top right
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . 8 . . 5 . . . |
$$ | . . . 4 . . . . . 6 . . . . . 1 . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . 7 . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . 2 . . . . . , . . . . . 3 . . . |
$$ | . . . . . . . . . . . . 9 . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]
Click Here To Show Diagram Code
[go]$$B White approaches the bottom right
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . 9 . . . 5 . . . |
$$ | . . . 4 . . . . . 6 . . . . . 1 . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . 7 . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . 2 . . . . . , . . . . . 3 . . . |
$$ | . . . . . . . . . . . . . 8 . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]
Which do you prefer for White?
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Re: Tewari analysis

Post by Cassandra »

There is a grave misanderstanding, I think.

Black 5: None of CrasyStone's (Top 10) candidate moves.

White 6: I think, it was in the Top 5, might be Top 3.

Black 7: I think, it was in the Top 3.

White 8 (at O3, Kakari in the lower right corner): Was the first move in the list.
Further down in the list, there appeared also a move in the upper right, but this was played as a Small Knights move, not as a Large Knights move, as you did.
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Re: Tewari analysis

Post by Bill Spight »

Clarifying questions:
Click Here To Show Diagram Code
[go]$$B White approaches the top right
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . 8 . . 5 . . . |
$$ | . . . 4 . . . . . 6 . . . . . 1 . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . 7 . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . 2 . . . . . , . . . . . 3 . . . |
$$ | . . . . . . . . . . . . 9 . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]
In this position, what probability does CS give for White to win?
Click Here To Show Diagram Code
[go]$$B White approaches the bottom right
$$ +---------------------------------------+
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . 9 . . . 5 . . . |
$$ | . . . 4 . . . . . 6 . . . . . 1 . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . , . . . . . , . . . . . 7 . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . 2 . . . . . , . . . . . 3 . . . |
$$ | . . . . . . . . . . . . . 8 . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]
In this position, what probability does CS give for White to win?

Thanks. :)
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Re: Tewari analysis

Post by Bill Spight »

Bantari wrote:
Bill Spight wrote:You need to develop your own judgement. Why rely upon authority? :)
I am not sure if you are joking here or not. In ase you are not, it seems to me a bit ironic.
Here we have a guy who did make his own mind (right or wrong) and a bunch of people argue that he should instead listen to either a dictionary or a stronger player.
I am not among them. :)
Then when he suggests to seek stronger players' input, he is told he should make his own mind instead. I don't get it.
When I offered the comparison to Pippen, I was pretty sure that he would prefer the first diagram for White, for the reasons that he gave. He is also aware of the reasons to prefer the second diagram. You do have to develop your own judgement, because in the end that's what you must rely upon. Pippen is aware of the main issues involved and, it seemed to me, had already made up his mind. But maybe not. If other opinions might lead him to reconsider, more power to him. :)
The Adkins Principle:
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— Winona Adkins

Visualize whirled peas.

Everything with love. Stay safe.
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