Win or draw?

Jouni · Post by **Jouni** » Thu Sep 20, 2007 9:54 am

[D]b2rk3/Q7/p3p3/P6p/2Pp3P/8/6P1/6K1 b - - 0 40

This is Grischuk und Svidler after possible 40. Qxa7. Was draw correct result or was Grischuk in time trouble maybe?

Jouni

Jouni · Post by **Jouni** » Thu Sep 20, 2007 5:07 pm

Hmm seems to be draw even if most engines give +2-+3 to white. Quite
difficult position!

Jouni

YL84 · Post by **YL84** » Sun Sep 30, 2007 4:57 pm

Hi,
very difficult position especially if you are stressed by time! Seems
difficult for black to lose due to the "d" passed pawn. for instance,
1...d3, 2. Qxa6 d2, 3. Qxe6+ Kf8 etc... White should take the draw by checks.
Below is Mylady 2.22 analysis PIII500MHz 384Mb RAM:

"depth 1 score -243 temps 1 nbnod 16 B_F :15 : d4d3
"depth 2 score -234 temps 2 nbnod 92 B_F :8,71779788708135 : d4d3 a7a6
"depth 3 score -220 temps 14 nbnod 414 B_F :6,85412400183262 : d4d3 a7a6 e6e5
"depth 4 score -248 temps 23 nbnod 1850 B_F :6,15585823772712 : d4d3 a7a6 e8e7 c4c5
"depth 5 score -251 temps 39 nbnod 4183 B_F :4,71609937532173 : d4d3 a7a6 e8e7 a6b5 d8d4
"depth 6 score -276 temps 87 nbnod 12320 B_F :4,48481004007794 : d4d3 a7a6 e8e7 a6a7 e7f6 a5a6
"depth 7 score -266 temps 170 nbnod 26537 B_F :3,91974920307388 : d4d3 a7a6 e8e7 a6b5 d8g8 b5c5 e7d7 :
"depth 8 score -324 temps 971 nbnod 158133 B_F :4,36420694497274 : d4d3 a7a6 e8e7 a6b5 d8h8 b5c5 e7f7 a5a6
"depth 9 score -310 temps 2398 nbnod 397596 B_F :3,95998150595583 : a8e4 a7a6 e4f5 a6b5 e8f8 a5a6 d4d3 a6a7 d3d2
"depth 10 score -355 temps 7945 nbnod 1257858 B_F :3,92159801374094 : d4d3 a7a6 e8e7 a6b5 d8g8 b5c5 e7f6 c5d4 e6e5 d4d3
"depth 11 score -312 temps 15301 nbnod 2494532 B_F :3,57965675019974 : a8e4 a7a6 e4f5 a6c6 e8e7 c6c7 d8d7 c7f4 f5g4 a5a6 d4d3
"depth 12 score -392 temps 73749 nbnod 11188761 B_F :3,7867728635468 : d4d3 a7a6 e8e7 a6a7 e7d6 a7b6 d6e7 b6c5 e7d7 c5e3 d7e7 e3g5
"depth 13 score -315 temps 176129 nbnod 24097631 B_F :3,52363895080772 : a8e4 a7a6 e4f5 a6c6 e8e7 c6c7 d8d7 c7c5 e7f7 a5a6 d4d3 a6a7 d3d2

Difficult for the engines to understand this position

Yves

Mike S. · Post by **Mike S.** » Sun Sep 30, 2007 5:30 pm

YL84 wrote:Seems difficult for black to lose due to the "d" passed pawn. (...) Difficult for the engines to understand this position

Yes, that includes Rybka 2.3.2a. I had posted the position from one move earlier, in the Rybkaforum because of the evaluation problems.

http://rybkaforum.net/cgi-bin/rybkaforu ... ?pid=25185

Only after some interactive analysis(*) in variations, up to the 46th move, Rybka would come up with

40.Qxa7 d3 41.Qxa6 d2 42.Qxe6+ Kf8 43.Qf5+ Ke8 44.Qxh5+ Ke7 45.Qd1 Be4 46.a6 Bc2
= (0.00) Depth: 14 00:00:00 16kN
= (0.00) Depth: 21 00:00:06 657kN

*) with 'Preserve Analysis' = ON

But initially, the engine assigned big + evals up to depth 25 and didn't have d3-d2 in the pv yet.

Jack Lad · Post by **Jack Lad** » Sun Sep 30, 2007 6:58 pm

Jouni wrote:Hmm seems to be draw even if most engines give +2-+3 to white. Quite
difficult position!

Jouni

White wins.

Mike S. · Post by **Mike S.** » Sun Sep 30, 2007 8:00 pm

Jack Lad wrote: White wins.

I don't think this is a quiz

Show me an improvement for white here:

40.Qxa7 d3 41.Qxa6 (41.Qe3 d2) 41...d2 42.Qxe6+ Kf8 43.Qf5+ Ke8 44.Qxh5+ Ke7 45.Qd1 Be4 46.a6 Bc2

I say White cannot win and it's backed up by interactive analysis with Rybka, with reasonable depths.

Jack Lad · Post by **Jack Lad** » Sun Sep 30, 2007 11:19 pm

Yes you are right it is drawn. I overlooked 41...d2.

YL84 · Post by **YL84** » Mon Oct 01, 2007 8:11 pm

Not very important, but the scores in my engine analyses are from black point of view (so -3 for black=+3 for white). Depth 13 is not enough to catch all the possibilities of perpetual check and passed pawn !
Yves

Eelco de Groot · Post by **Eelco de Groot** » Tue Oct 02, 2007 10:55 pm

YL84 wrote:Not very important, but the scores in my engine analyses are from black point of view (so -3 for black=+3 for white). Depth 13 is not enough to catch all the possibilities of perpetual check and passed pawn !
Yves

What do you guys think of this; the output from Tord's new Beta?

On an Athlon 2009 MHz, single thread only with 256 Mb hashtables. Used GUI was ChessPartner 5.4 interface which, as far as I know that is, still has a slightly different implementation of UCI analysis mode, using time control = infinite, I'm not sure it has an effect here.

The settings for Glaurung's 2.0 Beta extensions were slightly changed but as this is only a Beta, and I have not tested much, the changes are of course only an experiment.
Pawn pushes to the 7th rank are increased from one to two ply for both the PV and non-PV nodes, Single reply extensions are increased to two ply for PV nodes. I tried some other changes but most seemed not very successful. Recapture extensions for non-PV nodes seemed to be not working yet?

Glaurung 2.0 Beta 071001 "Mjolnir 001" finds a full drawscore in 5 minutes 41 seconds!

[D]b2rk3/Q7/p3p3/P6p/2Pp3P/8/6P1/6K1 b - - 0 1
00:00:00.3 -2,23 2 130 e5 Qxa6
00:00:00.3 -1,80 3 422 e5 Qxa6 Kd7 Qb5+ Kd6
00:00:00.3 -2,05 4 1357 e5 Kf2 e4 Qxa6 e3+ Kg3
00:00:00.3 -2,21 5 4738 e5 Qc5 e4 Qxh5+ Kd7 Qf7+ Kc6 Qe6+ Kc5 Qxa6
00:00:00.3 -2,86 6 8983 e5 Qc5 e4 Qxh5+ Ke7 Qh7+ Ke6 Qg6+ Kd7 Qxa6
00:00:00.3 -2,82 6 12488 Be4 Qxa6 Ke7 Qb5 Bd3 a6
00:00:00.3 -2,78 7 24605 Be4 Qxa6 Bf5 Qc6+ Ke7 a6 Rd6 Qb7+ Rd7 Qb4+ Rd6
00:00:00.3 -2,84 8 34711 Be4 Qxa6 Bf5 Qc6+ Ke7 a6 Rd6 Qc7+ Rd7 Qe5
00:00:00.4 -2,88 9 69845 Be4 Qxa6 Bf5 Qc6+ Ke7 a6 d3 a7 d2 Qc7+ Rd7 Qc5+ Kf6 a8Q d1Q+ Kf2
00:00:00.5 -2,78 10 177055 Be4 Qxa6 Bf5 Qc6+ Ke7 Qc5+ Kf6 Qb6 Ke7 a6 Rd6 Qb7+ Rd7 Qb4+ Rd6
00:00:00.8 -3,03 11 347916 Be4 Qxa6 Bf5 Qc6+ Ke7 a6 d3 Qc7+ Rd7 Qc5+ Kf6 Qf8+ Kg6 Qe8+ Rf7 Kf2
00:00:01.4 -3,09 12 802219 Be4 Qxa6 Bf5 Qc6+ Ke7 Qc7+ Rd7 Qc5+ Rd6 a6 d3 a7 d2 a8Q d1Q+ Kh2 Kf7 Qe5
00:00:02.7 -2,98 13 1683705 Be4 Qxa6 Bf5 Qc6+ Ke7 Qc7+ Rd7 Qc5+ Rd6 a6 d3 a7 d2 a8Q d1Q+ Kh2 Kf7 Qca7+ Rd7 Qe3
00:00:05.1 -3,03 14 3413333 Be4 Qxa6 Bf5 Qc6+ Ke7 Qc7+ Rd7 Qc5+ Rd6 Qe5 Kd7 Qg7+ Kc6 Qh8 Kc5 Qxh5 Kxc4 g4
00:00:12.0 -2,80 15 8265224 Be4 Qxa6 Bf5 Qc6+ Ke7 Qc5+ Ke8 Qb5+ Ke7 Qb4+ Ke8 Kf2 d3 Qd2 Kd7 Ke3 Ra8 Kd4 Kc6
00:00:19.6 -2,98 16 13735180 Be4 Qxa6 Bf5 Qb5+ Ke7 Qb4+ Ke8 Qa4+ Kf7 a6 d3 a7 d2 Qd1 Bg4 a8Q Rxa8 Qxd2 Ke7 Qb4+ Kf6 Kf2 Ra2+ Kg3
00:00:51.5 -3,23 17 36648719 Be4 Qxa6 Bf5 Qc6+ Ke7 a6 d3 Qc7+ Rd7 Qc5+ Kf7 a7 d2 a8Q d1Q+ Kh2 Rd8 Qb7+ Rd7 Qbc8 Rd8 Q5c7+ Ke8 Q8b7 Qd6+ Qxd6 Rxd6
00:01:16.7 -2,84 17 54956028 d3 Qxa6 Ke7 Qa7+ Rd7 Qc5+ Kd8 Qg5+ Kc8 Qd2 e5 Kf2 e4 Ke3 Bc6 c5 Rg7 a6 Rg3+ Kd4 Kd7
00:01:46.3 -3,01 18 76746167 d3 Qxa6 Ke7 Qa7+ Rd7 Qc5+ Kd8 Qg5+ Kc8 Qd2 e5 Kf2 e4 Ke3 Bc6 c5 Rg7 a6 Ra7 Qa2 Kd8
00:03:15.2 -1,98 19 137986295 d3 Qxa6 Ke7 Qa7+ Rd7 Qc5+ Rd6 Qg5+ Kd7 Qg7+ Kc6 Qg8 Kc5 Qg5+ Kxc4 Qxh5 d2 Qd1 Kb5 Kf2 Kxa5 g4 Kb4 Ke3 Bb7
00:05:41.2 0,00 20 242345741 d3 Qxa6 d2 Qxe6+ Kf8 Qf5+ Ke8 Qxh5+ Ke7 Qd1 Be4 a6 Bc2 Qe2+ Kf6 Qf2+ Bf5 Qb6+ Ke7 Qc7+ Rd7 Qe5+ Kd8 Qa5+ Ke8 Qe5+ Kd8
00:07:09.9 0,00 21 304290210 d3 Qxa6 d2 Qxe6+ Kf8 Qf5+ Ke8 Qxh5+ Ke7 Qd1 Be4 a6 Bc2 Qe2+ Kf6 Qf2+ Bf5 Qb6+ Ke7 Qc7+ Rd7 Qe5+ Kd8 Qa5+ Ke8 Qe5+ Kd8
00:09:30.3 0,00 22 402004278 d3 Qxa6 d2 Qxe6+ Kf8 Qf5+ Ke8 Qxh5+ Ke7 Qd1 Be4 a6 Bc2 Qe2+ Kf6 Qf2+ Bf5 Qb6+ Ke7 Qc7+ Rd7 Qe5+ Kd8 Qa5+ Ke8 Qe5+ Kd8
00:14:38.2 0,00 23 621775681 d3 Qxa6 d2 Qxe6+ Kf8 Qf5+ Ke8 Qxh5+ Ke7 Qd1 Be4 a6 Bc2 Qe2+ Kf6 Qf2+ Bf5 Qb6+ Ke7 Qc7+ Rd7 Qe5+ Kd8 Qa5+ Ke8 Qe5+ Kd8

Looks very good from Tord's new engine here!

Eelco

Alessandro Scotti · Post by **Alessandro Scotti** » Tue Oct 02, 2007 11:25 pm

Hamsters can also find the draw:

Code: Select all

Hamsters 0.5 by Alessandro Scotti
a b2rk3/Q7/p3p3/P6p/2Pp3P/8/6P1/6K1 b - - 0 1
 2/ 6 0&#58;00.00 -171 123 Be4 Qxa6
 3/ 8 0&#58;00.00 -172 405 Be4 Qxa6 Ke7
 4/ 9 0&#58;00.00 -168 968 Be4 Qxa6 Ke7 Qa7+ Kf6
 5/11 0&#58;00.00 -176 2751 Be4 Qxa6 Ke7 c5 e5
 6/15 0&#58;00.01 -214 11104 Be4 Qxa6 Bf5 Qb5+ Ke7 a6 Kf6
 7/17 0&#58;00.03 -216 20508 Be4 Qxa6 Bf5 Qb5+ Ke7 a6 Kf6 a7 Rg8
 8/19 0&#58;00.08 -217 49051 Be4 Qxa6 Bf5 Qc6+ Ke7 a6 d3 a7 d2 Qc7+ Rd7 Qc5+ Kf6 a8=Q d1=Q+ Kf2
 9/21 0&#58;00.15 -221 91661 Be4 Qxa6 Bf5 Qc6+ Ke7 Qc7+ Rd7 Qf4 Ra7 Qxd4 Rxa5
10/25 0&#58;00.41 -219 241736 Be4 Qxa6 Bf5 Qc6+ Ke7 Qc7+ Rd7 Qf4 Ke8 a6 Kf7 c5
11/27 0&#58;00.81 -218 479222 Be4 Qxa6 Bf5 Qc6+ Ke7 Qc7+ Rd7 Qf4 Bg4 a6 d3 Qg5+ Kf7 c5
12/27 0&#58;01.64 -213 976629 Be4 Qxa6 Bf5 Qc6+ Ke7 Qc7+ Rd7 Qf4 Bg4 a6 d3 Qd2 e5 c5
13/30 0&#58;02.61 -219 1555666 Be4 Qxa6 Bf5 Qc6+ Ke7 Qc7+ Rd7 Qf4 Bg4 a6 d3 Qd2 e5 c5 Ke6
14/31 0&#58;04.47 -227 2670178 Be4 Qxa6 Bf5 Qc6+ Ke7 Qc7+ Rd7 Qf4 Bg4 a6 d3 Qg5+ Kd6 Qe3 Ke7 a7 d2 a8=Q d1=Q+ Kh2
15/38 0&#58;10.24 -218 6028089 Be4 Qxa6 Bf5 Qc6+ Ke7 Qc7+ Rd7 Qc5+ Kf7 a6 d3 a7 d2 a8=Q d1=Q+ Kh2 Rd8 Qaa7+ Qd7 Qac7 Qxc7+ Qxc7+ Ke8 c5
16/41 0&#58;19.51 -222 11443650 Be4 Qxa6 Bf5 Qb5+ Kf7 Qb7+ Ke8 Qf3 Bg4 Qc6+ Ke7 Qc5+ Ke8 a6 d3 Qc6+ Ke7 Qc7+ Rd7 Qc5+ Kf6 a7 d2 Qg5+ Kf7 a8=Q d1=Q+ Kh2
17/42 0&#58;37.80 -221 22148776 Be4 Qxa6 Bf5 Qb5+ Kf7 Qb7+ Ke8 Qf3 Bg4 Qc6+ Ke7 Qc5+ Ke8 Qb5+ Kf7 Qg5 Rd7 a6 d3 Qd2 Ke7 c5
17/42 1&#58;28.18 -167 51509570 d3 Qxa6 Ke7 Qa7+ Rd7 Qc5+ Kd8 Qg5+ Kc8 Qd2 Be4 g3 e5 Kf2 Rf7+ Ke3 Bc6 Qh2 Rf3+ Kd2 e4 a6 Rf7 Qh3+ Kb8
18/46 3&#58;32.59 0 122136311 d3 Qxa6 d2 Qxe6+ Kf8 Qf5+ Ke7 Qg5+ Ke8 Qxh5+ Ke7 Qd1 Be4 a6 Bc2 Qe2+ Kf6 Qf2+ Bf5 Qb6+ Ke7 Qc7+ Rd7 Qe5+ Kd8 Qa5+ Ke7 Qe5+
19/51 5&#58;18.26 0 181466597 d3 Qxa6 d2 Qxe6+ Kf8 Qf5+ Ke7 Qg5+ Ke8 Qxh5+ Ke7 Qe5+ Kf7 Qf5+ Ke7 Qh7+ Kf6 Qh6+ Kf7 Qf4+ Ke8 Qe5+ Kf7

Win or draw?

Win or draw?

Re: Win or draw?

Re: Win or draw?

Re: Win or draw?

Re: Win or draw?

Re: Win or draw?

Re: Win or draw?

Re: Win or draw?

Re: Win or draw? Output from new Glaurung Beta.

Re: Win or draw? Output from new Glaurung Beta.