testposition from the topboard of the candidates

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Thomas Lagershausen
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Re: testposition from the topboard of the candidates

Post by Thomas Lagershausen » Sun Mar 29, 2020 8:02 am

zullil wrote:
Sat Mar 28, 2020 9:01 pm
Thomas Lagershausen wrote:
Sat Mar 28, 2020 8:11 pm

If you didn´t find an improvement in this moves it is proven that 23.f4 !! is best.
As I said in my very first reply, White already had a won position before move 23. A variety of twenty-third moves by White maintain the win.

Previously, you suggested that "best" meant "the shortest way to a full point". I doubt that 23. f4 gives the fastest win.
Right, this is my definition of "best".

Ok, to make it more clear for all this is my line of best moves for now (!):

23.f4!? Ne7 24.Rfb1 f5 25.Rb5 Qa6 26.Bc1 g6 27.Ba3 Rxb5 28.Rxb5 gxh5 29.Ng3 h4 30.Nh5 Rg8 30.Qb1 Qxa4 32.Bxe7 Kxe7 33.Rb7

and Stockfish gives the endposition a + 7,04 for white.

Please improve the defence for black or give me a bestmove-line till move 33 with Stockfish´s 23.Rxb6?! that evaluates Stockfish with more than +7 for white.
TL

zullil
Posts: 6073
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Location: PA USA
Full name: Louis Zulli

Re: testposition from the topboard of the candidates

Post by zullil » Sun Mar 29, 2020 9:57 am

Zenmastur wrote:
Sun Mar 29, 2020 1:35 am

I have this line at +4.09 which is much better than any of the lines you gave. It doesn't prove the OP is right, but it also doesn't support the idea that the OP is wrong either.

I trust your analysis. If you have a chance, please analyze 23. Rxb6. My guess is you'll be well over 4.09, without having to look very far ahead.

zullil
Posts: 6073
Joined: Mon Jan 08, 2007 11:31 pm
Location: PA USA
Full name: Louis Zulli

Re: testposition from the topboard of the candidates

Post by zullil » Sun Mar 29, 2020 10:00 am

Thomas Lagershausen wrote:
Sun Mar 29, 2020 8:02 am
zullil wrote:
Sat Mar 28, 2020 9:01 pm
Thomas Lagershausen wrote:
Sat Mar 28, 2020 8:11 pm

If you didn´t find an improvement in this moves it is proven that 23.f4 !! is best.
As I said in my very first reply, White already had a won position before move 23. A variety of twenty-third moves by White maintain the win.

Previously, you suggested that "best" meant "the shortest way to a full point". I doubt that 23. f4 gives the fastest win.
Right, this is my definition of "best".

Ok, to make it more clear for all this is my line of best moves for now (!):

23.f4!? Ne7 24.Rfb1 f5 25.Rb5 Qa6 26.Bc1 g6 27.Ba3 Rxb5 28.Rxb5 gxh5 29.Ng3 h4 30.Nh5 Rg8 30.Qb1 Qxa4 32.Bxe7 Kxe7 33.Rb7

and Stockfish gives the endposition a + 7,04 for white.

Please improve the defence for black or give me a bestmove-line till move 33 with Stockfish´s 23.Rxb6?! that evaluates Stockfish with more than +7 for white.
Look at 27...gxh5.

zullil
Posts: 6073
Joined: Mon Jan 08, 2007 11:31 pm
Location: PA USA
Full name: Louis Zulli

Re: testposition from the topboard of the candidates

Post by zullil » Sun Mar 29, 2020 4:39 pm

zullil wrote:
Sun Mar 29, 2020 9:57 am
Zenmastur wrote:
Sun Mar 29, 2020 1:35 am

I have this line at +4.09 which is much better than any of the lines you gave. It doesn't prove the OP is right, but it also doesn't support the idea that the OP is wrong either.

I trust your analysis. If you have a chance, please analyze 23. Rxb6. My guess is you'll be well over 4.09, without having to look very far ahead.
Here's what Stockfish gives after just a bit of forward/backward analysis:

+4.13 23. Rxb6 Nxb6 24. Ra1 Nc8 25. Bc1 Kd7 26. Rb1 Nb6 27. f4 Rb8 28. Kf2 Nxa4 29. Ra1 Rb3 30. Qa2 Qd8 31. Qxa4 Qh4+ 32. Ke3 Qxh5 33. Ra3 Rb6 34. Ra2 Qh4 35. Qa3 Qd8 36. Qd6+ Kc8 37. Qxd8+ Kxd8 38. Ba3 Rb5 39. Bf8 g6 40. Bxh6 Ke8 41. Ra6 Rb6 42. Rxb6 axb6 43. Nc1 Na7 44. Bg5 Nb5 45. Ne2 Kd7 46. Bh4 Na3 47. Be1 Nc2+ 48. Kf2 Na3 49. Kg3 Ke7 50. Kf3 Nc2 51. Bd2 f5 52. exf6+ Kxf6 53. Ng1 Na3 54. g4 Kg7 55. Ke2 Kg8 56. Nf3 Nb5 57. Kf2 (depth 47, 0:03:13)

Zenmastur
Posts: 826
Joined: Sat May 31, 2014 6:28 am

Re: testposition from the topboard of the candidates

Post by Zenmastur » Mon Mar 30, 2020 1:30 am

zullil wrote:
Sun Mar 29, 2020 4:39 pm
zullil wrote:
Sun Mar 29, 2020 9:57 am
Zenmastur wrote:
Sun Mar 29, 2020 1:35 am

I have this line at +4.09 which is much better than any of the lines you gave. It doesn't prove the OP is right, but it also doesn't support the idea that the OP is wrong either.

I trust your analysis. If you have a chance, please analyze 23. Rxb6. My guess is you'll be well over 4.09, without having to look very far ahead.
Here's what Stockfish gives after just a bit of forward/backward analysis:

+4.13 23. Rxb6 Nxb6 24. Ra1 Nc8 25. Bc1 Kd7 26. Rb1 Nb6 27. f4 Rb8 28. Kf2 Nxa4 29. Ra1 Rb3 30. Qa2 Qd8 31. Qxa4 Qh4+ 32. Ke3 Qxh5 33. Ra3 Rb6 34. Ra2 Qh4 35. Qa3 Qd8 36. Qd6+ Kc8 37. Qxd8+ Kxd8 38. Ba3 Rb5 39. Bf8 g6 40. Bxh6 Ke8 41. Ra6 Rb6 42. Rxb6 axb6 43. Nc1 Na7 44. Bg5 Nb5 45. Ne2 Kd7 46. Bh4 Na3 47. Be1 Nc2+ 48. Kf2 Na3 49. Kg3 Ke7 50. Kf3 Nc2 51. Bd2 f5 52. exf6+ Kxf6 53. Ng1 Na3 54. g4 Kg7 55. Ke2 Kg8 56. Nf3 Nb5 57. Kf2 (depth 47, 0:03:13)
I just started an analysis of 23.Rxb6. I'm not sure I'll have time to finish it but I'm already at +4.88 (this value WILL change) . The move 28. ... Nxa4 is probably a error because it, in effect, gives away the knight. If your going to take the pawn at all, I would suggest 28. ... Qxa4 is better although I'm not sure how much better.

I inadvertently left my computer analyzing the position 30.Qxh5 from the position I gave the other day (instead of 23.Rxb6) overnight and came up with +5.60 at depth 63.

I don't think this means too much, but it does mean that the black alternatives in this line at move 25.
would need to be investigated better than the cursory analysis I gave them the other day.

Regards,

Zenmastur
Only 2 defining forces have ever offered to die for you.....Jesus Christ and the American Soldier. One died for your soul, the other for your freedom.

Zenmastur
Posts: 826
Joined: Sat May 31, 2014 6:28 am

Re: testposition from the topboard of the candidates

Post by Zenmastur » Mon Mar 30, 2020 10:22 pm

I don't see any massive score increases from 23.Rxb6. It clearly wins, but that's it.


Code: Select all

( [Stockfish 250220 64 POPCNT] 62:+4.00 23...Nxb6 24.Ra1 Nc8 25.Bc1 Qd8 26.Rb1 Qe7 27.Qa2 g5 28.hxg6 fxg6 29.a5 Qf7 30.Qa4 Qd7 31.Nf4 Rg8 32.Ba3 Nxe5 33.Qxd7+ Nxd7 34.Nxe6 g5 35.Rb7 Rg6 36.Nc7+ Kd8 37.Nxd5 Ra6 38.Nb4 Rf6 39.Nc2 Rc6 40.Ne3 Rc7 41.Rb5 Rc6 42.d5 Nd6 43.Bxd6 Rxd6 44.Nxc4 Rf6 45.Rb7 Ra6 46.f3 h5 47.Kf2 g4 48.fxg4 hxg4 49.Kg3 Kc8 50.Rb5 Rf6 51.Ne3 Kc7 52.c4 a6 53.Rb1 Rf8 54.Nxg4 Rf7 55.Ne3 Rf8 56.Rh1 Kd6 57.Rh6+ Kc5 58.Rh7 Kd6 59.Kh4 )
Only 2 defining forces have ever offered to die for you.....Jesus Christ and the American Soldier. One died for your soul, the other for your freedom.

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