Crunch This!

Discussion of anything and everything relating to chess playing software and machines.

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PauloSoare
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Re: Crunch This!

Post by PauloSoare »

I can not see a win for white. Very hard for me,
and with computer help.
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AdminX
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Re: Crunch This!

Post by AdminX »

PauloSoare wrote:I can not see a win for white. Very hard for me,
and with computer help.
The debate was still running over at chessgames.com as well.

http://www.chessgames.com/perl/chessgam ... 44&kpage=1
"Good decisions come from experience, and experience comes from bad decisions."
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Ted Summers
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AdminX
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Re: Crunch This!

Post by AdminX »

Here is the best line that I could locate, with assistance of engines of course ... :D

[d]r1bQ1bk1/1q3p1p/4p1pP/3pP1B1/3N1P2/2P5/5RPK/8 w - - 0 4

49. Rb2 Qd7
50. Qf6 Ba6
51. Rb6 Bf1
52. Rd6 Qe8
53. Nc6 Bb5
54. Ne7 Qe7
55. Qe7 Be7
56. Be7 Rb8
57. Kg3 Bd3
58. Rd7

[d]1r4k1/3RBp1p/4p1pP/3pP3/5P2/2Pb2K1/6P1/8 b - - 0 58

Analysis by Deep Rybka 3 64-bit on a Q6700:

58...Bf1 59.Ra7 Re8 60.Bd6 Rc8 61.Kg4 Bb5 62.g3 Be8 63.Kg5 Bb5 64.Kf6
+/- (0.84) Depth: 25 00:00:00 0kN
+/- (0.85) Depth: 28 00:11:06 97021kN
"Good decisions come from experience, and experience comes from bad decisions."
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Ted Summers
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michiguel
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Re: Crunch This!

Post by michiguel »

AdminX wrote:Here is the best line that I could locate, with assistance of engines of course ... :D

[d]r1bQ1bk1/1q3p1p/4p1pP/3pP1B1/3N1P2/2P5/5RPK/8 w - - 0 4

49. Rb2 Qd7
50. Qf6 Ba6
51. Rb6 Bf1
52. Rd6 Qe8
53. Nc6 Bb5
54. Ne7 Qe7
55. Qe7 Be7
56. Be7 Rb8
57. Kg3 Bd3
58. Rd7

[d]1r4k1/3RBp1p/4p1pP/3pP3/5P2/2Pb2K1/6P1/8 b - - 0 58

Analysis by Deep Rybka 3 64-bit on a Q6700:

58...Bf1 59.Ra7 Re8 60.Bd6 Rc8 61.Kg4 Bb5 62.g3 Be8 63.Kg5 Bb5 64.Kf6
+/- (0.84) Depth: 25 00:00:00 0kN
+/- (0.85) Depth: 28 00:11:06 97021kN
I think this is not complicated. After Qd7 /Qxd7 Rxd7/ Rb7 white will take its Knight to f6. Black has an impossible time trying to stop this. With this simple plan in mind, black position crumbles.

Miguel
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AdminX
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Re: Crunch This!

Post by AdminX »

Where do you get Rxd7 from??
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M ANSARI
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Re: Crunch This!

Post by M ANSARI »

The position is most likely a draw. I keep ending up with a much better white position but with opposite bishops ... the black king can be totally blocked in and passive while white king is active ... yet he cannot take advantage of this activity because black bishop protects the important pawn. I did a Monte Carlo overnight analysis on my Octa and it confirms this. If there is a win, I sure can't find it ... but if it is there it most definetely would have to be refusing to exchange queens or rooks and manouevering with those pieces somehow to get an advantage.
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michiguel
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Re: Crunch This!

Post by michiguel »

AdminX wrote:Where do you get Rxd7 from??
Slip of my fingers :-). Of course, I meant Bxd7.

Miguel
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michiguel
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Re: Crunch This!

Post by michiguel »

M ANSARI wrote:The position is most likely a draw. I keep ending up with a much better white position but with opposite bishops ... the black king can be totally blocked in and passive while white king is active ... yet he cannot take advantage of this activity because black bishop protects the important pawn. I did a Monte Carlo overnight analysis on my Octa and it confirms this. If there is a win, I sure can't find it ... but if it is there it most definetely would have to be refusing to exchange queens or rooks and manouevering with those pieces somehow to get an advantage.
You have to exchange queens (do not exchange the knights!!!). Play Rb7, play Rc7 to secure c3 (maybe not needed), play Nf3-Nh2-Ng4-Nf6+ & Rxf7 or Nc2-Ne3-Ng4-Nf6+ & Rxf7. If black place the bishop on d1 or e2, chase it away with the King. I do not see how black can stop this. Black cannot move much.

This is the typical position where you do not solve it with search, you solve it with a plan based on what you need (the Knight at f6). Sort of a logical retrograde analysis. Long plans are generally beyond the horizon of engines.

Am I missing something? It sounds too easy.

Miguel
Terry McCracken
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Re: Crunch This!

Post by Terry McCracken »

michiguel wrote:
M ANSARI wrote:The position is most likely a draw. I keep ending up with a much better white position but with opposite bishops ... the black king can be totally blocked in and passive while white king is active ... yet he cannot take advantage of this activity because black bishop protects the important pawn. I did a Monte Carlo overnight analysis on my Octa and it confirms this. If there is a win, I sure can't find it ... but if it is there it most definetely would have to be refusing to exchange queens or rooks and manouevering with those pieces somehow to get an advantage.
You have to exchange queens (do not exchange the knights!!!). Play Rb7, play Rc7 to secure c3 (maybe not needed), play Nf3-Nh2-Ng4-Nf6+ & Rxf7 or Nc2-Ne3-Ng4-Nf6+ & Rxf7. If black place the bishop on d1 or e2, chase it away with the King. I do not see how black can stop this. Black cannot move much.

This is the typical position where you do not solve it with search, you solve it with a plan based on what you need (the Knight at f6). Sort of a logical retrograde analysis. Long plans are generally beyond the horizon of engines.

Am I missing something? It sounds too easy.

Miguel
No, you're on the right track and have the winning plan that computers can't find due to lack of knowledge and the horizon effect.

A top GM like Kramnik could win this in his sleep. In fact he goes for endgames not unlike this one.
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M ANSARI
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Re: Crunch This!

Post by M ANSARI »

Can you give this concrete line that wins by force. I seem to have a very active black rook with plenty of defensive resources that can turn the tables if not careful. If rooks can be exchanged and queens are off then this is very quickly a draw.