Author: Sune Larsson
Date: 22:27:30 12/22/01
Go up one level in this thread
On December 22, 2001 at 23:55:03, K. Burcham wrote:
>On December 22, 2001 at 20:33:43, martin fierz wrote:
>
>>On December 22, 2001 at 03:36:46, K. Burcham wrote:
>>
>>>in this game there was a big swing from a positive score of about five to a
>>>losing score of a mate in 11 in the final position. i have had several questions
>>>about this game since i found this out at that time. this game has been
>>>discussed here before. this was not a blitz game. shredders score
>>>gradually increased to the +5, and back to a mate in 11 with 80 moves. all this
>>>made me curious. here are my questions about this game.
>>>
>>>questions:
>>> 1. was there one or more blunders?
>>> 2. will some of the other top programs have this large eval swing?
>>> 4. how miscalculated was this plan by shredder to push its own two pawns?
>>> 5. can we find a key move in this game that will end in a draw?
>>> 6. will shredder duplicate the same eval, in an analysis?
>>> 7. one of the top programmers that post here, made this statement:
>>> "well we know we cant trust shredders eval, so we should not
>>> use this program to analyze games". i assumed he was basing
>>> that comment on this game. so is his statement true?
>>> 8. did deep junior eval also swing, the same as shredder?
>>> 9. when did deep junior see the problem shredder was in?
>>> 10. does this game indicate that deep junior can see far ahead
>>> of most programs?
>>>
>>>now i am able to get some accurate answers. with dual 1533 and 1 gig ram,
>>>i can run deep junior7. in the list below you will see i also used other
>>>programs to compare. i tried to keep most depths from about 12 to 15.
>>>deep junior was getting depths of 4 to 5 more than other programs.
>>>sometimes the post would hang during analysis. but i think this info
>>>is accurate. i started with move 21. shreddder was in book until about move 11.
>>>deep junior also did not have 11...Rc8 in its book. it seems stefan
>>>was using a different book than the commercial shredder5. maybe this was the
>>>shredder5.32 book, not sure. at move 21 shredder eval was up about one pawn.
>>>
>>>all scores are for white, deep junior7.
>>>
>>>deep junior7, shredder5, chess tiger 14.0, deep shredder, crafty 18.08
>>>
>>>21.Qh3 -.30 -1.25 -1.28 -.92 -.69
>>>31.Na4 -1.25 -3.05 -2.04 -2.88 -.2.05
>>>47.hxg4 -1.95 -4.08 -2.88 -4.25 -3.19
>>>55.Kh3 -1.76 -4.92 -4.52 -4.95 -3.00
>>>57.g5 -2.63 -5.37 -4.98 -5.40 -4.20
>>>61.Kh4 -1.75 -5.58 -3.92 -5.40 -3.25
>>>...a4 -1.08 -5.51 -3.62 -5.09 -3.00
>>>62.f6 -.92 -3.60 -3.60 -3.95 -2.95
>>>...Rb8 -.37 -2.00 -2.90 -2.80 -2.46
>>>63.Bf3 .00 -.27 -1.38 .00 -2.44
>>>...
>>>64.g6 +.20 +.45 .00 +.37 +.19
>>>...Rd8 +3.50 +2.33 +3.88 +5.50(Qc2) +4.36
>>>66.Qc2 +4.00 +4.75 +4.08 +5.15 +2.47
>>>69.Nxd5 +3.16 +7.06 +3.48 +5.40 +2.33
>>>...Kf7 +5.75 +7.35 +6.85 +7.50 +6.62
>>>71.Qf3 +6.10 +9.00 +10.85 +10.11 +8.44
>>>
>>>80...Kb6 mate in 11 stefan resigns
>>>
>>>with the above info all of my questions have been answered.
>>>i am not saying that any of these programs would have played the same lines as
>>>shredder to lead into this same game. but it is obvious that junior did not see
>>>the win any sooner than the other programs. although dj eval was lower than
>>>shredder considerably. shredder5 eval and large eval swing was a little more
>>>than the others. but most programs evals were similiar. also at move 71
>>>deep junior eval is still 3 points lower than others. so DJ7 eval is
>>>conservative on both ends. it seems to me that deep junior had no idea
>>>that it could promote and mate, before the other programs could see this.
>>>but in this game deep junior played for the win, and was the victor.
>>>
>>>i also studied some of the key moves in this game. after using ct14 and deep
>>>shredder i found that on move 48...Bxf5, 49.exf5, the two pawns could now
>>>advance forward for the queen. in the Maastricht game shredder did not see
>>>this combination. instead if shredder had played 48...Nc2,
>>>shredder wins. of course i know this was just one game. but dj was running
>>>on 2x1533 and getting deep search. with this only one move change, shredder
>>>wins. also slate and i tried another line with changing just one move in
>>>this game and shredder had a draw with slate. slate if you read this,
>>>i found another line that shredder could win.
>>>here is the one move change, 48...Nc2 that shredder wins this game.
>>>
>>>[Event "Maastrict 2001 with move 48...Nc2"]
>>>[Site "?"]
>>>[Date "2001.12.22"]
>>>[Round "6"]
>>>[White "Deep Junior"]
>>>[Black "Shredder5"]
>>>[Result "0-1"]
>>>[SetUp "1"]
>>>[FEN "1r5k/2qb3p/3p3b/p3pN2/N3P1P1/2P1n1P1/6B1/R3Q2K b - -"]
>>>
>>>1... Nc2 2. Qd1 Nxa1 3. Nxh6 Bxa4 4. Qxa4 Nb3 5. g5 Nc5 6. Qa2
>>>Rf8 7. Qd5 a4 8. Nf5 a3 9. g4 Qd7 10. Qa2
>>>Qa4 11. Kh2 Nxe4 12. c4 Rb8 13. c5 Qb3 14. Qe2
>>>a2 15. Qa6 Qb2 16. Qa7 Rg8 17. g6 hxg6 18. Nh6
>>>a1=Q 19. Qxa1 Qxa1 20. Nxg8 Nc3 21. Kh3 Ne2 22. Ne7 0-1
>>>
>>>
>>>this is 48.Nf5
>>> [D] 1r5k/2qb3p/3p3b/p3pN2/N3P1P1/2P1n1P1/6B1/R3Q2K b - -
>>>
>>>here is the complete game.
>>>[Event "WMCCC"]
>>>[Site "Maastricht"]
>>>[Date "2001.08.22"]
>>>[Round "6"]
>>>[White "Junior"]
>>>[Black "Shredder"]
>>>[Result "1-0"]
>>>
>>>1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 a6 6. Be3
>>>e6 7. Be2 Qc7 8. f4 b5 9. a3 Bb7 10. Bf3 Nbd7 11. Nde2 Rc8
>>>12. O-O Be7 13. Kh1 O-O 14. b4 Nb6 15. Qd3 Rfd8 16. f5 Nc4
>>>17. fxe6 fxe6 18. Bd4 Rd7 19. Bxf6 Bxf6 20. Bg4 Re7 21. Qh3
>>>Rce8 22. a4 bxa4 23. Bh5 Rf8 24. Bg4 Bc8 25. Rxa4 Ree8
>>>26. Raa1 g6 27. Qg3 Qb6 28. Bh3 Qxb4 29. Qd3 Bg7 30. Rfb1
>>>Qc5 31. Na4 Qc7 32. c3 Rf6 33. Nd4 Ref8 34. Nf3 Rf4 35. Nd4
>>>Re8 36. Rf1 Rxf1+ 37. Rxf1 Bd7 38. Ra1 Kh8 39. Qf1 g5
>>>40. Qd1 Ne5 41. g3 g4 42. Bg2 a5 43. Qc2 Rb8 44. Qc1 Nc4
>>>45. Qe1 Bh6 46. h3 Ne3 47. hxg4 e5 48. Nf5 Bxf5 49. exf5
>>>Nc2 50. Qd1 Nxa1 51. Qxa1 e4 52. Qd1 e3 53. Bf3 Bg7 54. Kg2
>>>Re8 55. Kh3 Qc4 56. Be2 Qc6 57. g5 Be5 58. Nb2 d5 59. Nd3
>>>Bxc3 60. Nf4 d4 61. Kh4 a4 62. f6 Rb8 63. Bf3 Qb5 64. g6
>>>Rd8 65. g7+ Kg8 66. Qc2 Rd6 67. Qa2+ Qb3 68. Bd5+ Rxd5
>>>69. Nxd5 Kf7 70. Qg2 d3 71. Qf3 Qb8 72. Qh5+ Ke6 73. Nxc3
>>>e2 74. Qg4+ Kf7 75. Kg5 h6+ 76. Kxh6 e1=Q 77. Qg6+ Ke6
>>>78. f7+ Kd7 79. Qxd3+ Kc7 80. Qc4+ Kb6 1-0
>>>
>>>final position. stefan resigns with two queens on board. 80...Qb6
>>>and mate in 11.
>>>
>>> [D] 1q6/5PP1/1k5K/8/p1Q5/2N3P1/8/4q3 w - -
>>>
>>>kburcham
>>
>>dear kburcham,
>>interesting analysis, but i think you have not got the right answer...
>>hmm, so you are basically saying that Bxf5 is supposed to be *the* mistake?
>>i looked at the game, and if one of my chess pupils had been black, he would
>>have gotten a serious talking-to! let me explain:
>>the position after 51. Qxa1 is clearly winning for black. if you ask any strong
>>chess player, he will tell you what the plan is: exchange queens - at any price,
>>for a pawn or two even. the *only* thing that can go wrong for black in this
>>position is that he will have a problem with his king, and this only happens
>>when there are queens on the board. besides, an exchange is not worth much in
>>the middle game, but decisive once you enter the endgame, and there is no other
>>pair of rooks on the board. this is what all strong humans know, and what
>>obviously even top programs have not got programmed into their evaluation. so,
>>returning to the position after 51.Qxa1, how should black proceed? since his
>>position is already completely winning, he doesnt have to win a second time by
>>queening the e-pawn. i'll suggest a line, you can try to improve for white. my
>>line is 'human' in the sense that i will just attempt to exchange queens. i do
>>this by activating my queen first, and look for a possible exchange. The white
>>moves are made by fritz 5.32 running in chessbase. mostly the move indicated got
>>by far the best evaluation.
>>
>>51. ..Qc4 52. Qd1 Rg8 53. Bf3 e4 54. Be2 Qa2 (menacing Qd2, game over) 55. Nb6?
>>Qd2 56. Qxd2 Bxd2 and i'm not going to look at this position any more, it is so
>>winning for black.
>>i find it very interesting that fritz 5.32 doesnt mind the queen exchange, and
>>would also not play 55. ...Qd2! itself. this clearly shows that this version of
>>fritz has no clue about what is going on here. since you have all top programs,
>>could you give this a try and see which program would exchange the queen here?
>>alternatively, white could play 55. Qxd6 Qxe2 56. Qxh6 Qxg4 57. Qf6+ Qg7 and
>>black has again achieved his goal of exchanging the queens.
>>
>>believe me, there is no other viable plan for black in this position than the
>>exchange of queens. i have made this experience too many times as the guy who
>>should have done anything to get the queens off the board, the last time our
>>team lost a match 4.5-3.5 in the highest swiss league where i allowed a
>>perpetual check in a winning position. i have seen my pupils lose games a piece
>>up because they were checkmated. of course these are kids, but it's the same
>>here. there is a nice website called www.chesscafe.com, there there used to be a
>>column of some guy teaching weaker players. his motto was GTS, "go to sleep": if
>>you are a piece up, trade the queens then you can GTS - else you always have
>>to keep your eyes open for surprises, just like in this game. do the test and
>>see which program will play ...Qd2. of course, other moves win too there, but
>>that's not the point - the point is, do the programs know = have it coded in
>>their evaluation, that being an exchange up is worth more once the queens are
>>gone?
>>
>>thanks & best regards
>> martin
>
>
>hello martin-----
>yes i see. thanks for the lesson. 51...Qc4 works well. forces queen
>exchange. i played this through with gambit tiger 2.0 and deep junior7.
>this line wins for shredder as you point out. that is amazing how we can change
>one move and the program wins. this is not the first time i have seen this.
>not a blunder, no eval change with either move.
>
>but here is a line tiger wanted to change in yours.
>i have not studied this line but i will.
>
>-3.10 17 147134136 53.Qxd6(Bf3) *Bg7* Bd5 Qf1+ Kh2 Qe2+ Kh3 Re8
Qd7 Rb8 Qd6 Rf8
>Qe6 Qe1 Nc5 e4 Qxe4 Qf1+ Qg2
53.-Qxa4 54.Qxh6 [54.Qxe5+ Bg7 55.f6 Qxg4] 54.- Qxg4 55.Qf6+ Qg7
is another way here, and in Martin's spirit. He's right about this
position.
Sune
>
>here is a position tiger plays into after changing to your 51...Qc4. tiger says
>mate in 9.
>[D] 8/8/2N5/6k1/4p3/6P1/3b2K1/4r3 b - - 14 1
>
>also i am going to let deep junior run all night 2x1533mhz, to see if it will
>play 55...Qd2 and force the queen exchange. it is at depth 23, and has not
>played it yet.
>
>kburcham
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.