Yes, different moves (or different moves order). But for me it's all the same variant - black kill white's stones and white save H6Gérard TAILLE wrote:Yes Dany I agree with you but I still do not see how black has to play in order that all white moves are forced (no variation).dany wrote:In the original position, the interesting variation remains hidden behind Ichiriki solution. I do not like it. In the modified position the interesting variation becomes a solution and Ichiriki solution becomes a strong false idea))
As an example in the following position: white can choose between several moves can't she?
Subtilities for ko threats handling
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Re: Subtilities for ko threats handling
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Re: Subtilities for ko threats handling
BTW I think the area in the bottom left corner was not handled correctly for a strict local point of view (no impact for the Ichiriki problem)dany wrote:Yes, different moves (or different moves order). But for me it's all the same variant - black kill white's stones and white save H6Gérard TAILLE wrote:Yes Dany I agree with you but I still do not see how black has to play in order that all white moves are forced (no variation).dany wrote:In the original position, the interesting variation remains hidden behind Ichiriki solution. I do not like it. In the modified position the interesting variation becomes a solution and Ichiriki solution becomes a strong false idea))
As an example in the following position: white can choose between several moves can't she?
white can create another threat by to reach the following position which is a pass-alive position
Instead it seems technically strictly better for white to play white can still create another threat by to reach the following position which is NOT a pass-alive position
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Re: Subtilities for ko threats handling
For the black moves it is worse: In original Ichiriki problemdany wrote:Yes, different moves (or different moves order). But for me it's all the same variant - black kill white's stones and white save H6Gérard TAILLE wrote:Yes Dany I agree with you but I still do not see how black has to play in order that all white moves are forced (no variation).dany wrote:In the original position, the interesting variation remains hidden behind Ichiriki solution. I do not like it. In the modified position the interesting variation becomes a solution and Ichiriki solution becomes a strong false idea))
As an example in the following position: white can choose between several moves can't she?
is the best move.With the modified position it seems black can still reach the best result by beginning with "a" instead of
in the diagram above.-
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Re: Subtilities for ko threats handling
I do not think soGérard TAILLE wrote:
For the black moves it is worse: In original Ichiriki problem
With the modified position it seems black can still reach the best result by beginning with "a" instead of
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Re: Subtilities for ko threats handling
OK, let's try and if I am not wrong black reaches her best result (white wins by 0.5 point).dany wrote:I do not think soGérard TAILLE wrote:
For the black moves it is worse: In original Ichiriki problem
With the modified position it seems black can still reach the best result by beginning with "a" instead of
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Re: Subtilities for ko threats handling
Oops sorry Dany, you are right.dany wrote:W+1.5
Finally, with the modified position the only weakness is when the position above is reached. From that point both players may have several choices beginning with black who can play a, b, c or d.
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Re: Subtilities for ko threats handling
No choices. The only road (black can play 1,3,5 in any order)Gérard TAILLE wrote:Oops sorry Dany, you are right.dany wrote:W+1.5
Finally, with the modified position the only weakness is when the position above is reached. From that point both players may have several choices beginning with black who can play a, b, c or d.
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Re: Subtilities for ko threats handling
Again it is right Danydany wrote:No choices. The only road (black can play 1,3,5 in any order)Gérard TAILLE wrote:Oops sorry Dany, you are right.dany wrote:W+1.5
Finally, with the modified position the only weakness is when the position above is reached. From that point both players may have several choices beginning with black who can play a, b, c or d.
The sequence above cannot be an alternative because white has a ko threat available at "a". Not that obvious is it?
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Re: Subtilities for ko threats handling
In this thread about ko threats handling I showed you a problem dealing with ko threat order. In the following one the idea is to deal with the value of ko threats : do I have to answer a ko threat or is it better to play an exchange? This issue is quite difficult for players who are not strong enough to count precisely the result of the game.
Here is an example:
The upper right corner is not settled and black has the opportunity either to get a seki or to fight a ko in the corner. White has a ko threat in the lower left corner but is this ko threat big enough?
The remaining part of the board is quite simple : a small yose in the center of the board.
Would you able to count correctly and find the best sequence in a real game? (as far as I am concerned I am not
)
What is the result of the game?
Here is an example:
The upper right corner is not settled and black has the opportunity either to get a seki or to fight a ko in the corner. White has a ko threat in the lower left corner but is this ko threat big enough?
The remaining part of the board is quite simple : a small yose in the center of the board.
Would you able to count correctly and find the best sequence in a real game? (as far as I am concerned I am not
)What is the result of the game?
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Re: Subtilities for ko threats handling
It's too hard for me too. In 15 minutes I can evaluate all the variations. But I almost certainly won't be able to do it in a real game
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Re: Subtilities for ko threats handling
First of all I am happy to see you like such problem because I had to take a lot of time to build such position.dany wrote:It's too hard for me too. In 15 minutes I can evaluate all the variations. But I almost certainly won't be able to do it in a real game
I often can (but not so easily
) count correctly the result of a small variation but here, with several variations and some of these being rather long, I get easily confused. At the end I am completly lost : it appears I counted some variations sevaral time and I forgot easily my previous counts.For me such problem is an interesting challenge for players aiming at finding a rigourous approach for playing an endgame with an unclear ko remaining on the board. Sure I will make some progress by trying to be more rigourous in my approach.
Basically I have (at least) two difficulties : the visualization of all variations and the need to find the exact result for all of them.
What is for you the main difficulty? The number of variations or/and the need to count all of them?
Knowing you are 4 dan, do you think such endgame can be solved in real game by a very strong amateur?
BTW what is the result of the game according to your analyse?
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Re: Subtilities for ko threats handling
Have you heard about the real yose-and-ko monsterFirst of all I am happy to see you like such problem because I had to take a lot of time to build such position.
created by Cho U?Such problems are a good way to improve your reading skills. if you look at this position again and again, then over time, the calculation will become easier. My second attempt 7 minI often can (but not so easily
For me such problem is an interesting challenge for players aiming at finding a rigourous approach for playing an endgame with an unclear ko remaining on the board. Sure I will make some progress by trying to be more rigourous in my approach.
Visualization and sometimes calculationBasically I have (at least) two difficulties : the visualization of all variations and the need to find the exact result for all of them.
What is for you the main difficulty? The number of variations or/and the need to count all of them?
I think 6-7 dan can do it in a real gameKnowing you are 4 dan, do you think such endgame can be solved in real game by a very strong amateur?
B+0.5BTW what is the result of the game according to your analyse?