Author: F. Jermann
Date: 23:11:03 09/01/01
Go up one level in this thread
On September 01, 2001 at 19:46:27, Slater Wold wrote: >[D]3r3k/2qNb1r1/1p2pn2/pBpbNp2/Q2P1Pp1/P3P3/1PR3P1/2R2K2 b - - > >What is the correct move here? > >Had you asked Deep Thought back in 1989, it would say 33...Be4. > >However I could not get Deep Shredder to see this move in any reasonable amount >of time. (10+ minutes.) Gambit Tiger 2.0 aggr. thinks Le4 is good (about -1.17 for black), but Sxd7 Sxd7 and then Le4 is even better (about -1.7, score at depth 13) from the very beginning of analysis. Only the first several iterations, Le4 seems to be the best. I think GT analysis may be correct here! > >But is it correct? Well, considering 33...Be4 leads to 34. Rd2 Nd5 35. Re2, >then YES, it would be correct. > >However, are there other moves to stop this? Well at depth 12, and 5+ minutes >into evaluation, Deep Shredder would play 34. Rd2 after 33...Be4. That leaves >us with: > >[D]3r3k/2qNb1r1/1p2pn2/pBp1Np2/Q2PbPp1/P3P3/1P1R2P1/2R2K2 b - - > >This move seems pretty difficult to get also. Deep Shredder looked at Bd5 up to >ply 11, and then changed to Rh7 after 2:44 minutes, scoring itself up +0.25. GT 2.0: Rh7, -1.33 for black >After 4:36 minutes, it scores Rh7 as +0.47. Nd5 secures a little more position, >and leads to: > >[D]3r3k/2qNb1r1/1p2p3/pBpnNp2/Q2PbPp1/P3P3/1P1R2P1/2R2K2 w - - > >There are several moves that are possible here. From Qb3, Kg1, Re2, Re1, >however all are losing. After 3+ minutes, Deep Shredder plays Kg1, scoring >itself down -0.58. GT 2.0: Kg1, eval -0.56. So from GT view Rh7 is much stronger! Re2 seems to be worse for white: 3r3k/2qNb1r1/1p2p3/pBpnNp2/Q2PbPp1/P3P3/1P2R1P1/2R2K2 b - - 0 1 Analysis by Gambit Tiger 2.0: 35...Th7 36.Ke1 Th1+ 37.Kd2 Txc1 38.Kxc1 cxd4+ 39.Lc4 d3 µ (-0.80) Tiefe: 7 00:00:00 35kN 35...Th7 36.Ke1 Th1+ 37.Kd2 Txc1 38.Kxc1 cxd4+ 39.Kd1 d3 µ (-0.76) Tiefe: 7 00:00:00 55kN 35...Th7 36.Ke1 Th1+ 37.Kd2 Txc1 38.Kxc1 cxd4+ 39.Lc4 Kg7 40.exd4 Sxf4 µ (-0.98) Tiefe: 8 00:00:02 200kN 35...Th7 36.Ke1 Th1+ 37.Kd2 Txc1 38.Kxc1 µ (-0.98) Tiefe: 9 00:00:05 399kN 35...Th7 36.Tee1 Kg7 37.Ke2 Lxg2 38.Kd2 Sf6 39.Te2 Sxd7 40.Txg2 Sxe5 41.fxe5 -+ (-1.42) Tiefe: 10 00:00:41 3612kN 35...Th7 36.Tee1 Kg7 37.Ke2 Th2 38.Kd2 Txg2+ 39.Te2 Sxe3 40.dxc5 Lxc5 41.Txg2 Lxg2 µ (-1.34) Tiefe: 11 00:02:02 10287kN >However, the move that was played, was Re2. I will follow >through with the move that was played originally: > >[D]3r3k/2qNb1r1/1p2p3/pBpnNp2/Q2PbPp1/P3P3/1P2R1P1/2R2K2 b - - > >Now it becomes clear what moves are best. Deep Shredder scored this +1.41 for >itself in 0:00 seconds. After 31 seconds, it drops to +1.16. What about what >Shredder wanted earlier, Kg1, would that have saved it? No, it still plays Rh7, >and the score is even worse. (Which makes me wonder, how did it think Kg1 was >better!) > >After this, it is a clear win for black. But how did this happen? At move 33 >Deep Shredder says that Nxd7 is best, and thinks it's winning by a little over >0.30. Playing a better 33...Be4! and 2 moves later it's +2.00?! With Be4, and >a forced Rd2, we know that there is no good response to Nd5 or Rh7, and it's a >clear win for black!. This is only 2 moves away! This seems baffling to me, >and I hope someone can help explain. 33..Be4 only has one response. And we >know after 34. Rd2 it's a simple win for black. So why can't any programs find >it? It seems simple. > >Nxd7 is not the correct move, as it just exchanges pieces, and gives white a >better chance to draw. Be4 is winning, clearly. > >QUESTION: > >In this postiton, who can find 33...Be4! And find it in a tournament time? >(3-5 minutes) > >[D]3r3k/2qNb1r1/1p2pn2/pBpbNp2/Q2P1Pp1/P3P3/1PR3P1/2R2K2 b - - > >Here is Deep Shredder eval: > >position: > 10.01 0:01 +0.38 1...Nxd7 2.Bxd7 Qxd7 3.Qxd7 Rxd7 4.Nxd7 cxd4 (474.972) >467.4 > 11.01 0:02 +0.38 1...Nxd7 2.Bxd7 Qxd7 3.Qxd7 Bxg2+ 4.Rxg2 Rxd7 5.Nxd7 e5 >(1.204.841) 478.8 > 12.01 0:06 +0.38 1...Nxd7 2.Bxd7 Qxd7 3.Nxd7 Rxd7 (3.187.564) 477.7 > 13.01 0:30 +0.38 1...Nxd7 2.Bxd7 Qxd7 3.Qxd7 Rxd7 4.Nxd7 Bh4 5.dxc5 Bf3 >6.gxf3 (13.921.049) 460.6 >best move: Nf6xd7 time: 5:12.688 min n/s: 445.376 CPU 199.3% nodes: >139.263.904 > > >Thanks. And good luck! > > > >Slate Gambit Tiger continuously thinks it wins with black! I do not agree that Sxd7 is really bad for black in the position at move 33. GT likes it and all variations seem to show that is a really interesting attacking (!) move! See: Neue Partie - Gambit Tiger 2.0 3r3k/2qnb1r1/1p2p3/pBpbNp2/Q2P1Pp1/P3P3/1PR3P1/2R2K2 w - - 0 1 Analysis by Gambit Tiger 2.0: 34.Lxd7 Lf6 35.Lc6 Lxe5 36.Lxd5 Lxd4 37.exd4 Txd5 38.dxc5 bxc5 ³ (-0.58) Tiefe: 6 00:00:00 36kN 34.Lxd7 Th7 35.Le8 Ld6 36.Sg6+ Kg7 37.dxc5 bxc5 ³ (-0.42) Tiefe: 6 00:00:00 40kN 34.Lxd7 Th7 35.Le8 Ld6 36.Sg6+ Kg7 37.dxc5 bxc5 38.Db5 ³ (-0.42) Tiefe: 7 00:00:01 74kN 34.Lxd7 µ (-1.32) Tiefe: 8 00:00:02 173kN 34.Lxd7 Lf6 35.Lb5 Lxe5 36.fxe5 Db7 37.Ke2 Lxg2 38.Kd2 De4 -+ (-1.60) Tiefe: 9 00:00:03 273kN 34.Sxd7 Le4 35.dxc5 Lxc2 36.Txc2 bxc5 37.b4 axb4 38.axb4 g3 39.bxc5 -+ (-1.56) Tiefe: 9 00:00:05 430kN 34.Sxd7 Le4 -+ (-1.56) Tiefe: 10 00:00:05 457kN 34.Sxd7 Le4 35.Se5 Lf6 36.Db3 Lxc2 37.Txc2 Lxe5 38.fxe5 De7 39.Lc4 cxd4 40.Lxe6 -+ (-1.62) Tiefe: 11 00:00:20 1604kN 34.Sxd7 Le4 35.Se5 Lf6 36.Dc4 Lxc2 37.Txc2 Td5 38.Ke2 Lxe5 39.fxe5 Kg8 40.Kd2 -+ (-1.60) Tiefe: 12 00:00:48 3681kN 34.Sxd7 Le4 35.Se5 Lf6 36.Dc4 Lxc2 37.Txc2 Td5 38.Db3 Lxe5 39.fxe5 Kg8 40.Ke2 -+ (-1.76) Tiefe: 13 00:02:14 11316kN Frank
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.