Author: Joshua Lee
Date: 10:09:13 10/08/01
Go up one level in this thread
On October 07, 2001 at 05:45:18, Jeremiah Penery wrote: >On October 06, 2001 at 23:45:19, Slater Wold wrote: > >>Bruce and I have disagreed in the past that DJ7 can "solve" Nolot #3. He >>believes that DJ7 simply "prefers" Nxg5, because it doesn't have an impressive >>eval. Well, I believe I have found the reason! >> >>Here is the position: >>[D]r2qk2r/ppp1b1pp/2n1p3/3pP1n1/3P2b1/2PB1NN1/PP4PP/R1BQK2R w KQkq - 0 1 >> >>Here are Baudot's words: >> >>Smaguine - Sahovic, Bienne 1990 >> >>White wins with a queen sac but black has several ways to defend 12.Nxg5!! Bxd1 >>13.Nxe6 Qb8 14.Nxg7!! Kf8 15.Bh6! Bg4 16.0-0+ 17.Kg8 17.Rf4 +- >> >>It should take between a few months and a few years for a program to find >>12.Nxg5!! >> >>Here was DJ7's original solution: >> >>Deep Junior 7 - W,S >>r2qk2r/ppp1b1pp/2n1p3/3pP1n1/3P2b1/2PB1NN1/PP4PP/R1BQK2R w KQkq - 0 1 >> >>Analysis by Deep Junior 7: >> ><snip> >>1.Nxg5 Bxd1 2.Nxe6 Qb8 3.Nxg7+ Kd8 4.Kxd1 b5 5.Bf5 b4 6.Kc2 a5 7.Ne6+ Kd7 8.Bh6 >>a4 9.cxb4 >> ± (0.72) Depth: 20 00:07:17 757031kN >> >>Look at the mainline though. Baudot's line is a *tad* different. Instead of >>Kf8, DJ7 believe (and therefore evaluates) Kd8. >> >>I played through, with DJ7, and here's what I got: ><snip> >>Here is a recap: >> >>Deep Junior 7 - W,S >>Level=180"av. , 06.10.2001 >> >>1.Nxg5 0.68/18 3:48 Bxd1 2.Nxe6 0.72/20 3:26 Qb8 3.Nxg7+ 0.54/19 2:44 >>Kf8 4.Bh6 1.16/17 2:09 Bg4 5.0-0+ 1.96/17 2:13 Kg8 6.Rf4 2.08/17 1:00 >>1-0 >> >>It choose, step by step, each move. With _no_ problem. >> >>But what about Kf8? Is it the best move? Here is what I get: >> >>W,S - Deep Junior 7 >>rq2k2r/ppp1b1Np/2n5/3pP3/3P4/2PB2N1/PP4PP/R1BbK2R b KQkq - 0 1 >> >>Analysis by Deep Junior 7: >> ><snip> >>3...Kd8 4.Kxd1 b5 5.Bf5 b4 6.Kc2 Qb5 7.Ne6+ Kd7 8.b3 Qa6 9.cxb4 >> ² (0.70) Depth: 15 00:00:08 14218kN >>3...Kd8 4.Kxd1 b5 5.Bf5 b4 6.Kc2 Rg8 7.Ne6+ Kc8 >> ² (0.57) Depth: 18 00:03:19 325791kN >>3...Kd8 4.Kxd1 b5 5.Bf5 b4 6.Kc2 Rg8 7.Ne6+ Kc8 >> ² (0.57) Depth: 18 00:03:40 363183kN > >You didn't give the full commentary from the DT team. They pretty much agree >with you, and here's what they had to say (edited slightly by me): >Smaguine - Sahovic, Bienne 1990 > >12. Nxg5!! Bxd1 13. Nxe6 Qb8 14. Nxg7!! Kf8 15. Bh6! Bg4 16. 0-0+ >17. Kg8 17. Rf4 +- > >Solution move is 1. Nxg5!. Verified that the move is sound by following >the published analysis, but could not play it within one hour time. This >is more a positional sac than what would be normally called tactics. > >We took a closer look at this position. 12. Nxg5 is a sound positional >sac, but depending on the temperament of the player, it might not be >the best move. The published annotation gives 12. Bxg5 Bxg5 13. O-O as >+=, but white could play 13. h3 instead and white appears to have a simple >positional squeeze. The critical line in the 12. Nxg5 variation turns out >to be 12. Nxg5 Bxd1 13. Nxe6 Qb8 14. Nxg7 Kd8 15. Kxd1. Black's queen and rooks >are temporarily out of play, black is up a pawn, but white has a protected >passed pawn, and lots of pressure. (The annotator gave one line that >ended "with the attack":). From DT-2's point of view, The Bxg5 line was >gaining 0.20 pawn after each iteration, and so was the Nxg5 line. Except >that the Bxg5 line has about a 0.20 pawn lead at the same depth. There >appears to be no kill in the Nxg5 line when black king goes to d8 >instead of the f file. Black would have to give up the extra pawn to >activate the queen and the rooks, and while white is definitely better, black >is not without counter play. On the deepest search that we checked out, >black's evaluation stopped dropping at around -1.4 pawns, and black's pieces >were becoming active. Nobody Stated the actual rules to determine "IF" a position is solved, If Deep Junior 7 Solves this amazing considering in the line 1.Nxg5 Bxd1 2.Nxe6 Qc8 3. Nxg7+ Kf7 4. Bh6 it will take Chess Tiger 14 2 hours and 18 Ply to find a +- score 4... Bg4 5. O-O+ 1.46/16 13:53 How long will it take to reach 24 Ply from the start?? I don't have Deep Fritz or Junior 7, Deep Junior , Nimzo, Shredder , or Rebel so someone else may solve it quicker but right now this +- score is the quickest and the best of all the programs i have.
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