opening when chess programs are wrong

Discussion of anything and everything relating to chess playing software and machines.

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Jeroen
Posts: 501
Joined: Wed Mar 08, 2006 9:49 pm

Re: opening when chess programs are wrong

Post by Jeroen »

I once did a lot of analysis on the Traxler (I wanted to include it in the TCEC 9 superfinal set), after reading "Black Gambits 2" by Boris Alterman. If I recall correctly:

* 5.Nxf7 is a forced draw (in the diagram), or else rather equal
* 5.Bxf7+! is simple and strong, giving white the advantage
* 5.d4!? is another way to claim a white advantage
Jeroen
Posts: 501
Joined: Wed Mar 08, 2006 9:49 pm

Re: opening when chess programs are wrong

Post by Jeroen »

Correct, 5.d4! is also very strong.
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Eelco de Groot
Posts: 4565
Joined: Sun Mar 12, 2006 2:40 am
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Re: opening when chess programs are wrong

Post by Eelco de Groot »

fastgm wrote:[d]r1bqk2r/pppp1ppp/2n2n2/2b1p1N1/2B1P3/8/PPPP1PPP/RNBQK2R w KQkq - 6 5

Komodo 11.01 64-bit: Intel E5-2670, 16 Threads, 8 GB Hash

42 1:52:45 136.750.414k 20.213k +0,80 5.Sxf7 Lxf2+ 6.Kf1 De7 7.Sxh8 d5 8.exd5 Sd4 9.d6 Dxd6 10.Sf7 Dc5 11.d3 Lg4 12.Dd2 Lh4 13.Sc3 b5 14.Sxe5 Dxe5 15.De3 Dxe3 16.Lxe3 Sxc2 17.Lxb5+ Ld7 18.Ke2 Lxb5 19.Sxb5 Sd5 20.Ld4 Sxa1 21.Txa1 Kd7 22.Sc3 Sxc3+ 23.bxc3 Te8+ 24.Kf3 Lf6 25.Lxf6 Tf8 26.Tf1 Txf6+ 27.Ke2 Te6+ 28.Kd2 Ta6 29.Tf7+ Kd6 30.Txg7 Txa2+ 31.Ke3 a5 32.h3 Tc2 33.g4 Txc3 34.Txh7 a4 35.Th6+ Kc5 36.Ta6
43 6:57:43 477.499.230k 19.051k +0,74 5.Lxf7+ Ke7 6.Lb3 De8 7.d3 d6 8.c3 Tf8 9.Sf3 Dg6 10.0-0 Lg4 11.Kh1 Sh5 12.Sh4 Lxd1 13.Sxg6+ hxg6 14.Lg5+ Ke8 15.Lxd1 Txf2 16.Txf2 Lxf2 17.g3 Sd8 18.Lb3 Sf7 19.Ld2 Lc5 20.Sa3 Ke7 21.Sb5 Lb6 22.Kg2 Sf6 23.Tf1 Tf8 24.Sa3 a6 25.Sc4 Lc5 26.h3 Sd8 27.Lc2 Se6 28.Sa5 b6 29.Sc6+
44 12:49:30 870.640.343k 18.857k +0,70 5.Lxf7+ Ke7 6.Lb3 De8 7.d3 d6 8.c3 Tf8 9.Sf3 Lg4 10.Sbd2 Dg6 11.0-0 Kd8 12.Kh1 Dh5 13.La4 Kc8 14.Kg1 Dg6 15.Sh4 Dh5 16.Sdf3 Lb6 17.Lc2 h6 18.h3 Ld7 19.Le3 Lxe3 20.fxe3 Se7 21.La4 Lxa4 22.Dxa4 De8 23.Dxe8+ Txe8 24.Sd2 Kd7 25.Shf3 a5 26.Kf2 a4 27.Ke2 Tf8 28.d4 Sc6 29.Tad1 a3 30.dxe5
45 17:32:43 1.188.920.782k 18.823k +0,78 5.Lxf7+ Ke7 6.Lc4 Tf8 7.Sc3 De8 8.0-0 h6 9.Sf3 d6 10.Sd5+ Sxd5 11.exd5 Sd4 12.Sxd4 Lxd4 13.Le2 Dg6 14.d3 Lh3 15.Lf3 Tf6 16.Le4 Dg4 17.Dxg4 Lxg4 18.Le3 Lxe3 19.fxe3 Taf8 20.Txf6 Txf6 21.Tf1 Ld7 22.Txf6 Kxf6 23.Lf3 a5 24.Kf2 La4 25.b3 Ld7 26.e4 b5 27.c3 b4 28.cxb4 axb4 29.Ke3 g6 30.d4 g5 31.h3
Komodo finally found it! The result is a bit unflattering mainly because it takes the program long to resolve a new move with PV search at high depths. Depth 43 is higher for Komodo than for Stockfish although surely in the past this difference was larger. My latest version of search.cpp for Stockfish MOD also can't reach high iterations here, but the actual depths at each iteration reached are higher I hope see below.
Debugging is twice as hard as writing the code in the first
place. Therefore, if you write the code as cleverly as possible, you
are, by definition, not smart enough to debug it.
-- Brian W. Kernighan
User avatar
Eelco de Groot
Posts: 4565
Joined: Sun Mar 12, 2006 2:40 am
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Re: opening when chess programs are wrong

Post by Eelco de Groot »

Jeroen wrote:Correct, 5.d4! is also very strong.
Thanks Jeroen! By the way I did not really know this was called the Traxler variation :oops:

I tried experimenting a bit with giving the Knight in the corner a higher penalty for zero mobility, but because the penalty only works if the piece is really threatened and here it can return immediately to a square protected by bishop and threatened only by king and queen so that did not really work. I kept the penalty in though (and the knight does seem more stuck in a corner in the 7..d5 vaiation). The only way then was hoping to find 7...d5 {!} after 7. Nxh8 sooner causing Nxf7 to Fail Low. This with an old style search (old fashioned because of seemingly high Branching Factor) and a bit a la Crafty using a nullmove scout search on top of PV nodes.


r1bqk2r/pppp1ppp/2n2n2/2b1p1N1/2B1P3/8/PPPP1PPP/RNBQK2R w KQkq -

Engine: Sf20170524_031 HT MOD (i7 6700, 4 threads + 3 hyperthreads, 512 MB)
by T. Romstad, M. Costalba, J. Kiiski, G. Linscott

21/38 0:01 +1.41 1.Nxf7 Bxf2+ 2.Kxf2 Nxe4+ 3.Kg1 Qh4
4.g3 Nxg3 5.Nxh8 Nxh1 6.d3 d5 7.Bxd5 Nf2
8.Qf3 Nh3+ 9.Kg2 Nf4+ 10.Bxf4 Nd4
11.Qe4 Qxf4 12.Qxf4 exf4 13.Na3 c6
14.Re1+ (15.054.742) 9852

22/38 0:05 +1.69-- 1.Nxf7 Bxf2+ (52.294.452) 9985

22/38 0:05 +1.41-- 1.Nxf7 Bxf2+ (58.348.635) 9986

22/39 0:06 +1.30 1.Nxf7 Bxf2+ 2.Kxf2 Nxe4+ 3.Kg1 Qh4
4.g3 Nxg3 5.Nxh8 Nxh1 6.d3 Nf2 7.Qf3 Qg4+
8.Kxf2 Qxf3+ 9.Kxf3 Nd4+ 10.Ke4 d5+
11.Kxd5 Nxc2 12.Na3 Nxa1 13.Kxe5 Bd7
14.Nf7 (60.851.151) 9987

23/39 0:06 +1.23-- 1.Nxf7 Bxf2+ (65.821.681) 9986

23/39 0:15 +1.30++ 1.Nxf7 (153.373.144) 9725

23/39 0:16 +1.41++ 1.Nxf7 (156.072.873) 9713

23/39 0:16 +1.42 1.Nxf7 Bxf2+ 2.Kf1 Qe7 3.Nxh8 Bb6
4.Nc3 d6 5.Bf7+ Kd8 6.Nd5 Qf8 7.d3 Qxh8
8.Bg5 Ne7 9.Nxb6 axb6 10.Bb3 Qf8
11.Qf3 Bg4 12.Qf2 h6 13.Be3 Kc8
14.h3 (158.021.725) 9702

24/39 0:17 +1.49++ 1.Nxf7 (168.918.209) 9643

24/39 0:18 +1.49 1.Nxf7 Bxf2+ 2.Kf1 Qe7 3.Nxh8 Bb6
4.Bf7+ Kd8 5.Nc3 Qf8 6.d3 d6 7.Nd5 Qxh8
8.Bg5 Ne7 9.Nxb6 axb6 10.Bb3 Qe8
11.h3 Qg6 12.Qd2 Bd7 13.Kg1 Kc8
14.Kh2 (174.455.397) 9620
.
.
.
32/52 5:04 +1.44 1.Nxf7 Bxf2+ 2.Kf1 Qe7 3.Nxh8 Bb6
4.Bf7+ Kf8 5.Nc3 d6 6.h3 Be6 7.g3 Bxf7
8.Nxf7 Qxf7 9.Kg2 Qg6 10.Rf1 Nd4
11.d3 Kg8 12.a4 c6 13.a5 Bc7 14.a6 (2.773.109.093) 9103

33/52 5:53 +1.51++ 1.Nxf7 (3.218.193.954) 9093

33/52 6:21 +1.58++ 1.Nxf7 (3.463.472.156) 9084

33/52 6:45 +1.69++ 1.Nxf7 (3.684.912.979) 9085

33/52 7:14 +1.60-- 1.Nxf7 Bxf2+ (3.942.923.003) 9079

33/52 8:46 +1.39-- 1.Nxf7 Bxf2+ (4.796.984.993) 9104

33/52 10:58 +1.11-- 1.Nxf7 Bxf2+ (6.010.978.254) 9130


33/52 15:44 +0.95 1.Bxf7+ Ke7 2.Bb3 d6 3.d3 Qe8 4.Be3 Bxe3
5.fxe3 Qg6 6.Nf3 Bd7 7.Nc3 Rhf8
8.Qd2 Rae8 9.O-O-O Kd8 10.Rhf1 Kc8
11.Ba4 a6 12.Nd5 b5 13.Bb3 Nxd5
14.Bxd5 (8.598.090.033) 9104

34/52 19:33 +1.02++ 1.Bxf7+ (10.616.376.145) 9046

34/52 22:02 +1.02 1.Bxf7+ Ke7 2.Bb3 d6 3.d3 Rf8 4.Be3 Bxe3
5.fxe3 Bd7 6.Nf3 Qe8 7.Qe2 Kd8 8.Nc3 Kc8
9.O-O-O Ne7 10.d4 Ng6 11.a4 a6 12.a5 Kb8
13.Qc4 h6 14.Rhe1 (11.889.014.032) 8991

35/52 25:06 +0.95-- 1.Bxf7+ Ke7 (13.429.638.473) 8917

35/52 36:53 +0.87-- 1.Bxf7+ Ke7 (19.312.749.748) 8726

35/57 55:33 +0.77-- 1.Bxf7+ Ke7 (28.643.316.526) 8592

35/57 58:34 +0.85++ 1.Bxf7+ (30.179.102.292) 8586

35/57 66:58 +0.81 1.Bxf7+ Ke7 2.Bd5 d6 3.c3 Qe8 4.Bxc6 Qxc6
5.d3 Rf8 6.O-O Bg4 7.Nf3 Qe8 8.Bg5 h6
9.Be3 Bxe3 10.fxe3 Kd8 11.Nbd2 Kc8
12.h3 Bd7 13.Nh4 a5 14.Nf5 (34.391.725.921) 8559

36/57 71:53 +0.89++ 1.Bxf7+ (36.896.982.371) 8552

36/57 77:44 +0.81-- 1.Bxf7+ Ke7 (39.895.830.831) 8552

36/57 86:49 +0.89++ 1.Bxf7+ (44.520.898.327) 8546

36/57 90:21 +0.79-- 1.Bxf7+ Ke7 (46.338.098.857) 8546

36/57 95:28 +0.73 1.Bxf7+ Ke7 2.Bc4 Qe8 3.Nc3 Rf8
4.O-O h6 5.Nf3 d6 6.Be2 Kd8 7.a3 a5
8.d3 Qg6 9.Nh4 Qf7 10.Be3 Nd4 11.Bf3 g5
12.Nf5 Qh7 13.h3 Bxf5 14.exf5 (48.959.715.011) 8546

37/57 108:37 +0.81++ 1.Bxf7+ (55.583.916.596) 8528

37/57 112:03 +0.88++ 1.Bxf7+ (57.296.949.560) 8521

37/57 114:17 +0.83 1.Bxf7+ Ke7 2.Bc4 Qe8 3.Nc3 Rf8
4.O-O h6 5.Nf3 d6 6.Be2 Kf7 7.d3 Be6
8.Na4 Bb6 9.Bd2 Kg8 10.b4 Ne7 11.c4 Bd7
12.Nxb6 axb6 13.h3 Ng6 14.Be3 (58.409.884.756) 8517

38/57 120:10 +0.90++ 1.Bxf7+ (61.357.895.938) 8509

38/57 122:18 +0.83-- 1.Bxf7+ Ke7 (62.414.446.481) 8505

38/57 123:25 +0.90++ 1.Bxf7+ (62.974.122.301) 8503

38/57 136:55 +0.81-- 1.Bxf7+ Ke7 (69.875.525.534) 8505

38/57 144:16 +0.84 1.Bxf7+ Ke7 2.Bc4 Qe8 3.Nc3 h6 4.Nf3 d6
5.O-O Rf8 6.Be2 Kf7 7.d3 Bb6 8.Na4 Ba5
9.c3 Bd7 10.Qc2 Kg8 11.Bd2 a6
12.Rac1 Kh8 13.Bd1 b5 14.b4 (73.637.498.794) 8507

39/57 151:28 +0.91++ 1.Bxf7+ (77.295.377.384) 8504

39/57 151:57 +0.84-- 1.Bxf7+ Ke7 (77.540.183.219) 8504

39/57 157:11 +0.91++ 1.Bxf7+ (80.228.970.631) 8506

39/57 158:21 +0.82-- 1.Bxf7+ Ke7 (80.831.396.138) 8506

39/57 159:23 +0.85 1.Bxf7+ Ke7 2.Bc4 Qe8 3.Nc3 Rf8
4.O-O h6 5.Nf3 d6 6.Be2 Kf7 7.d3 Kg8
8.Na4 Bb6 9.c3 Ne7 10.Nxb6 axb6
11.Be3 Ng6 12.Nd2 d5 13.f3 Be6 14.d4 (81.357.039.805) 8506

40/57 161:28 +0.78-- 1.Bxf7+ Ke7 (82.414.017.535) 8506

40/57 163:44 +0.85++ 1.Bxf7+ (83.571.823.972) 8506

40/57 172:03 +0.89 1.Bxf7+ Ke7 2.Bc4 Qe8 3.Nc3 Rf8
4.O-O h6 5.Nf3 d6 6.Nd5+ Nxd5 7.exd5 Nd4
8.Nxd4 Bxd4 9.Be2 Qg6 10.d3 Bh3
11.Bf3 Rf6 12.Kh1 Bd7 13.c3 Bb6
14.a4 (87.759.619.705) 8500

41/57 176:46 +0.81-- 1.Bxf7+ Ke7 (90.135.599.496) 8498

41/57 185:46 +0.86 1.Bxf7+ Ke7 2.Bc4 Qe8 3.Nc3 h6 4.Nf3 d6
5.O-O Rf8 6.Be2 Kf7 7.d3 Kg8 8.Na4 Bb6
9.Nxb6 axb6 10.h3 Qf7 11.b3 b5
12.Bb2 Be6 13.a3 Qg6 14.Kh1 (94.729.485.296) 8498

42/59 216:33 +0.85 1.Bxf7+ Ke7 2.Bc4 Qe8 3.Nc3 h6 4.Nf3 d6
5.O-O Rf8 6.Nd5+ Nxd5 7.exd5 Nd4
8.Nxd4 Bxd4 9.Be2 Kf7 10.Bh5+ g6
11.Bf3 Kg7 12.d3 Qe7 13.Qe2 Bb6
14.c3 (110.514.858.727) 8505

43/59 398:41 +0.77-- 1.Bxf7+ Ke7 (204.121.964.820) 8533

43/59 414:38 +0.85++ 1.Bxf7+ (212.273.502.535) 8532

43/59 439:01 +0.77-- 1.Bxf7+ Ke7 (224.679.527.196) 8529

43/59 488:40 +0.86++ 1.Bxf7+ (249.939.564.289) 8524
Debugging is twice as hard as writing the code in the first
place. Therefore, if you write the code as cleverly as possible, you
are, by definition, not smart enough to debug it.
-- Brian W. Kernighan
Jeroen
Posts: 501
Joined: Wed Mar 08, 2006 9:49 pm

Re: opening when chess programs are wrong

Post by Jeroen »

In the 5.Nxf7 line (which is weaker than 5.Bxf7+ or 5.d4) it is interesting to have the engines investigate the following position, which arises after 5.Nxf7 Qe7 6.Nxh8 Bxf2+ 7.Kf1 d5 8.exd5 Nd4 9.d6 Qxd6 10.Nf7:

[d]r1b1k3/ppp2Npp/3q1n2/4p3/2Bn4/8/PPPP1bPP/RNBQ1K1R b q - 0 10

There are now two moves possible: 10... Qc5 and 10... Qe7. Very complicated stuff. If I recall correctly, 10... Qc5 still gives white the better chances, while 10... Qe7! (posted by Uri) is a forced draw.

Maybe you could give both moves a try? Perhaps there is something very deep in the 10... Qc5 line, although I could not find it in 2016.
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Eelco de Groot
Posts: 4565
Joined: Sun Mar 12, 2006 2:40 am
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Re: opening when chess programs are wrong

Post by Eelco de Groot »

Jeroen wrote:In the 5.Nxf7 line (which is weaker than 5.Bxf7+ or 5.d4) it is interesting to have the engines investigate the following position, which arises after 5.Nxf7 Qe7 6.Nxh8 Bxf2+ 7.Kf1 d5 8.exd5 Nd4 9.d6 Qxd6 10.Nf7:

[d]r1b1k3/ppp2Npp/3q1n2/4p3/2Bn4/8/PPPP1bPP/RNBQ1K1R b q - 0 10

There are now two moves possible: 10... Qc5 and 10... Qe7. Very complicated stuff. If I recall correctly, 10... Qc5 still gives white the better chances, while 10... Qe7! (posted by Uri) is a forced draw.

Maybe you could give both moves a try? Perhaps there is something very deep in the 10... Qc5 line, although I could not find it in 2016.
Hi Jeroen,

Well, I just let it run a while in Multi-PV = 2 to save some time, doing both moves at once. 10...Qe7 is tough to find the forced draw (found at depth 32 with this search) so some engines or players, without a good book, might be caught off guard and go for 10... Qc5 which is at least not a forced 0.00 But otherwise it would seem that Nxf7 is refuted by 10...Qe7 against someone who knows. Hiarcs' book apparently still has Nxf7 in, going by what Jon Dart posted earlier in the thread.

Of course because I just let it run from your diagram the quality of the PV probably leaves much to be desired but the value seems stable and the computerline too. But going back and forth or setting up some kind of tree would probably help you more. Endvalue is ≈ 0.66 for White that seems a decent plus

The moveorder as you gave it, I would not include in your book 8-)



r1b1k3/ppp2Npp/3q1n2/4p3/2Bn4/8/PPPP1bPP/RNBQ1K1R b q -

Engine: Sf20170524_031 HT MOD (512 MB)
by T. Romstad, M. Costalba, J. Kiiski, G. Linscott


40 79:00 0.00 6...Qe7 7.h3 Bh4 8.c3 Nf5 9.Na3 b5
10.d4 bxc4 11.Nxe5 Bb7 12.Naxc4 Ne4
13.Kg1 Bf2+ 14.Kh2 Bg3+ 15.Kg1 Bf2+ (46.849.171.205) 9882

40 79:00 +0.61 6...Qc5 7.d3 Bg4 8.Qd2 Bh4 9.Nc3 b5
10.b4 Qb6 11.Bd5 Nxd5 12.Nxd5 Qc6
13.Nxe5 Qxd5 14.Nxg4 O-O-O 15.Bb2 Re8
16.Qf4 Nxc2 17.Rc1 Bg5 18.Qf3 Qxf3+
19.gxf3 Bxc1 (46.849.171.205) 9882
_____________________________________________

41 97:28 0.00 6...Qe7 7.h3 Bh4 8.c3 Nf5 9.Na3 b5
10.d4 bxc4 11.Nxe5 Bb7 12.Naxc4 Ne4
13.Kg1 Bf2+ 14.Kh2 Bg3+ 15.Kg1 Bf2+
(57.989.902.712) 9914

41 97:28 +0.64 6...Qc5 7.d3 Bg4 8.Qd2 Bh4 9.Nc3 b5
10.b4 Qb6 11.Bd5 Nxd5 12.Nxd5 Qb7
13.Nxe5 Qxd5 14.Nxg4 O-O-O 15.Bb2 Re8
16.Qf4 Nxc2 17.Rc1 Bg5 18.Qf3 Qxf3+
19.gxf3 Bxc1 (57.989.902.712) 9914
_____________________________________________

42 127:22 0.00 6...Qe7 7.h3 Bh4 8.c3 Nf5 9.Na3 b5
10.d4 bxc4 11.Nxe5 Bb7 12.Naxc4 Ne4
13.Kg1 Bf2+ 14.Kh2 Bg3+ 15.Kg1 Bf2+
(76.080.709.028) 9955

42 127:22 +0.72 6...Qc5 7.d3 Bg4 8.Qd2 Bh4 9.Nc3 b5
10.b4 Qb6 11.Bd5 Nxd5 12.Nxd5 Qc6
13.Nxe5 Qxd5 14.Nxg4 O-O-O 15.Bb2 Re8
16.Qf4 Nxc2 17.Rc1 Bg5 18.Qf3 Qxf3+
19.gxf3 Bxc1 (76.080.709.028) 9955
______________________________________________

43 166:14 0.00 6...Qe7 7.h3 Bh4 8.c3 Nf5 9.Na3 b5
10.d4 bxc4 11.Nxe5 Bb7 12.Kg1 O-O-O
13.Bf4 g5 14.Bd2 Nxd4 15.cxd4 Rxd4
16.Naxc4 Qc5 17.b4 Rg4+ 18.bxc5 Rxg2+
19.Kf1 Rf2+ (99.265.714.724) 9952

43 166:14 +0.66 6...Qc5 7.d3 Bg4 8.Qd2 Bh4 9.Nc3 b5
10.b4 Qb6 11.Bd5 Nxd5 12.Nxd5 Qb7
13.Nxe5 Qxd5 14.Nxg4 O-O-O 15.Bb2 Re8
16.Qf4 Nxc2 17.Rc1 Bg5 18.Qf3 Qxf3+
19.gxf3 Bxc1 (99.265.714.724) 9952
______________________________________________

44 245:06 0.00 6...Qe7 7.h3 Bh4 8.c3 Nf5 9.Na3 b5
10.d4 bxc4 11.Nxe5 Bb7 12.Kg1 O-O-O
13.Bd2 Nxd4 14.cxd4 Rxd4 15.Naxc4 Qc5
16.b4 Rxd2+ 17.bxc5 Rxg2+ 18.Kf1 Rf2+
19.Kg1 Rg2+ (146.704.805.190) 9975

44 245:06 +0.52 6...Qc5 7.d3 Bg4 8.Qd2 Bh4 9.Nc3 b5
10.b4 Qe7 {Now we diverge} 11.Bb3 Nd5 12.Bxd5 Qf6+
13.Kg1 Be2 14.Bf3 Bxf3 15.Qe3 Kxf7
16.gxf3 Nxf3+ 17.Kg2 Qg6+ 18.Kxf3 Qh5+
19.Kg2 Qg4+ (146.704.805.190) 9975


(This Stockfish MOD to be made available later, for who is interested)
Debugging is twice as hard as writing the code in the first
place. Therefore, if you write the code as cleverly as possible, you
are, by definition, not smart enough to debug it.
-- Brian W. Kernighan
Jeroen
Posts: 501
Joined: Wed Mar 08, 2006 9:49 pm

Re: opening when chess programs are wrong

Post by Jeroen »

44 245:06 +0.52 6...Qc5 7.d3 Bg4 8.Qd2 Bh4 9.Nc3 b5 10.b4 Qe7 {Now we diverge} 11.Bb3 Nd5 12.Bxd5 Qf6+ 13.Kg1 Be2 14.Bf3 Bxf3 15.Qe3 Kxf7 16.gxf3 Nxf3+ 17.Kg2 Qg6+ 18.Kxf3 Qh5+ 19.Kg2 Qg4+ (146.704.805.190) 9975
OK, +0.52 doesn't look bad. But if we continue that line: 20.Qg3 Bxg3 21.hxg3 Qxb4 22.Bd2, I must say that I really like white here!

[d]r7/p1p2kpp/8/1p2p3/1q6/2NP2P1/P1PB2K1/R6R b - - 0 26

Instead of 7... Bg4 there is another possibility (I am using your move number, the actual move number is 11): 7... e4 8.b4 Qf5 9.dxe4 Nxe4 and now 10.g4! Qg6 11.h3 is just very good for white.

[d]r1b1k3/ppp2Npp/6q1/8/1PBnn1P1/7P/P1P2b2/RNBQ1K1R b q - 0 15
User avatar
Eelco de Groot
Posts: 4565
Joined: Sun Mar 12, 2006 2:40 am
Full name:   

Re: opening when chess programs are wrong

Post by Eelco de Groot »

Hi Jeroen!

I had two more iterations but they do not change much, not in the moves anyway. I am glad here I got to at least depth 46, I still have to investigate why sometimes there are no new depths, but engine does not crash (I think it is also Stockfish that has this problem). I think you probably will have found this same sequence of moves, if not I have a problem :) Because it all seems almost forced if White wants to have some evaluation advantage. Sometimes he can choose something different but that leads quickly to a 0.00 variation or direct loss. And Black sometimes can choose something different with little loss but he does not have to because this seems to be a draw. Even though at times White still was the rook up, he makes no progres whatsoever (Or else I have a bug...)

r1b1k3/ppp2Npp/3q1n2/4p3/2Bn4/8/PPPP1bPP/RNBQ1K1R b q -

Engine: Sf20170524 HT MOD (512 MB)
by T. Romstad, M. Costalba, J. Kiiski, G. Linscott

45 305:10 0.00 6...Qe7 7.h3 Bh4 8.c3 Nf5 9.Na3 b5
10.d4 bxc4 11.Nxe5 Bb7 12.Kg1 O-O-O
13.Bd2 Nxd4 14.cxd4 Rxd4 15.Naxc4 Qc5
16.b4 Rxd2+ 17.bxc5 Rxg2+ 18.Kf1 Rf2+
19.Kg1 Rg2+ (182.965.461.862) 9992

45 305:10 +0.75 6...Qc5 7.d3 Bg4 8.Qd2 Bh4 9.Nc3 b5
10.b4 Qb6 11.Bd5 Nxd5 12.Nxd5 Qc6
13.Nxe5 Qxd5 14.Nxg4 O-O-O 15.Bb2 Re8
16.Qf4 Nxc2 17.Rc1 Bg5 18.Qf3 Qxf3+
19.gxf3 Bxc1 (182.965.461.862) 9992


r1b1k3/ppp2Npp/3q1n2/4p3/2Bn4/8/PPPP1bPP/RNBQ1K1R b q -

Engine: Sf20170524_031 HT MOD (512 MB)
by T. Romstad, M. Costalba, J. Kiiski, G. Linscott

46 514:16 0.00 6...Qe7 7.h3 Bh4 8.c3 Nf5 9.Na3 b5
10.d4 bxc4 11.Nxe5 Bb7 12.Kg1 O-O-O
13.Bd2 Nxd4 14.cxd4 Rxd4 15.Naxc4 Qc5
16.b4 Rxd2+ 17.bxc5 Rxg2+ 18.Kf1 Rf2+
19.Kg1 Rg2+ (305.650.376.518) 9905

46 514:16 +0.69 6...Qc5 7.d3 Bg4 8.Qd2 Bh4 9.Nc3 b5
10.b4 Qb6 11.Bd5 Nxd5 12.Nxd5 Qb7
13.Nxe5 Qxd5 14.Nxg4 O-O-O 15.Bb2 Re8
16.Qf4 Nxc2 17.Rc1 Bg5 18.Qf3 Qxf3+
19.gxf3 Bxc1 (305.650.376.518) 9905

OK, +0.52 doesn't look bad. But if we continue that line: 20.Qg3 Bxg3 21.hxg3 Qxb4 22.Bd2, I must say that I really like white here!

[d]r7/p1p2kpp/8/1p2p3/1q6/2NP2P1/P1PB2K1/R6R b - - 0 26
Yes at the end last night I got to exactly the same position that you have posted today, assuming Black plays 14...Qe7 and not 14...Qb6 as in the line above (10...Qb6 Shredder output starting with the diagram of your post) going forward and checking quickly for alternatives. 14...Qe7 seemed a tad better in eval than 14...Qb6 when I got there. It seemed all forced so Stockfish can do a lot of Singular Extensions and will probably look pretty deep. My Stockfish does not do Probcut in such cases, so if exchanges are more or less forced I think I look deeper than Stockfish and the cost is low (no real alternatives)

[pgn][Event "?"]
[Site "?"]
[Date "2017.06.20"]
[Round "?"]
[White "?"]
[Black "?"]
[Result "*"]
[SetUp "1"]
[FEN "r1bqk2r/pppp1ppp/2n2n2/2b1p1N1/2B1P3/8/PPPP1PPP/RNBQK2R w KQkq -"]

1. Nxf7 Bxf2+ 2. Kf1 Qe7 3. Nxh8 d5 4. exd5 Nd4 5. d6 Qxd6
6. Nf7 Qc5 7. d3 Bg4 8. Qd2 Bh4 9. Nc3 b5 10. b4 Qe7
11. Bb3 Nd5 12. Bxd5 Qf6+ 13. Kg1 Be2 14. Bf3 Bxf3 15. Qe3
Kxf7 16. gxf3 Nxf3+ 17. Kg2 Qg6+ 18. Kxf3 Qh5+ 19. Kg2 Qg4+
20. Qg3 Bxg3 21. hxg3 Qxb4 *[/pgn]

Here I declared it a draw. The material is unbalanced but Black has Queen and two pawns for a Rook, Bishop and Knight. So materially you could argue even if Queen = 9 points, Rook = 5 Bishop = Knight =3.
Unbelievable such a long string of forced moves, more than twenty full moves or am I seeing mirages :o

[D]r7/p1p2kpp/8/1p2p3/1q6/2NP2P1/P1P3K1/R1B4R w - -

Engine: Sf20170524_031 HT MOD (512 MB)
by T. Romstad, M. Costalba, J. Kiiski, G. Linscott

41 22:41 +0.35 22.Bd2 Qc5 23.Rxh7 Kg6 24.Rh4 Rf8
25.Kh3 Rf5 26.Rc1 Qf8 27.Re1 Qc5
28.a4 b4 29.Rc4 Qf2 30.Rg4+ Kf7
31.Ne4 Rh5+ 32.Rh4 Qf5+ 33.Kh2 a5
34.Rxh5 Qxh5+ 35.Kg1 (13.723.292.134) 10078

40 22:41 0.00 22.Ne4 Kg8 23.Be3 Qa4 24.Rhc1 b4
25.Bf2 Rb8 26.Kf3 a5 27.Ke2 Rd8
28.Kd2 Qb5 29.Re1 Qc4 30.Bc5 h6
31.Re2 Qb5 32.Bf2 Rd5 33.Ke1 Rd8
34.Kd2 (13.723.292.134) 10078

40 22:41 0.00 22.Rf1+ Kg8 23.Bd2 Qc5 24.a3 Qc6+
25.Rf3 Rf8 26.Ne4 Rxf3 27.Kxf3 Qxc2
28.Ke2 Qb2 29.Rc1 Qxa3 30.Rxc7 b4
31.Ng5 Kf8 32.Rb7 a5 33.Ne6+ Ke8
34.Nxg7+ Kd8 35.Nf5 (13.723.292.134) 10078

best move: Bc1-d2 time: 22:41.672 min n/s: 10.078.280 nodes: 13.723.292.134
Debugging is twice as hard as writing the code in the first
place. Therefore, if you write the code as cleverly as possible, you
are, by definition, not smart enough to debug it.
-- Brian W. Kernighan
Jeroen
Posts: 501
Joined: Wed Mar 08, 2006 9:49 pm

Re: opening when chess programs are wrong

Post by Jeroen »

Hi Eelco!

Only +0.35 for this position!? Hmmm, I'd like to see some LTC matches between Komodo, Houdini and Stockfish from this position to confirm that black can hold the draw.... I still think white must be able to create winning chances, somehow.

[d]r7/p1p2kpp/8/1p2p3/1q6/2NP2P1/P1PB2K1/R6R b - - 0 26
fastgm
Posts: 818
Joined: Mon Aug 19, 2013 6:57 pm

Re: opening when chess programs are wrong

Post by fastgm »

[d]r1bq3r/ppppkBpp/2n2n2/2b1p1N1/4P3/8/PPPP1PPP/RNBQK2R w KQ - 1 6

Till depth 50:

asmFishL_2017-05-22_bmi2: Intel E5-2686 v4, 32 Threads, 64 GB Hash

34/58 06:02 18.301.134k 50.522k +0,73 6.Bc4 Qe8 7.d3 d6 8.c3 Bg4 9.f3 Bd7 10.f4 exf4 11.Bxf4 h6 12.Nf3 Rf8 13.Qe2 Nh5 14.Be3 Bxe3 15.Qxe3 Nf4 16.Rg1 Qh5 17.Nbd2 Rae8 18.g3 Nh3 19.Rf1 Kd8 20.0-0-0 Kc8 21.d4 Kb8 22.Bd3 a6 23.Kb1 Bg4 24.Be2 Rf6 25.d5
35/58 06:13 18.897.146k 50.553k +0,79 6.Bc4 Qe8 7.d3 d6 8.c3 Bg4 9.f3 Bd7 10.f4 Bb6 11.Qe2 Qh5 12.f5 Qxe2+ 13.Kxe2 g6 14.fxg6 hxg6 15.Nf3 Bg4 16.Bg5 Bxf3+ 17.Kxf3 Raf8 18.Ke2 Rh5 19.h4 Rxg5 20.hxg5 Ng4 21.b4 Rf2+ 22.Ke1 Rxg2 23.Nd2 Be3 24.Nf1 Bxg5 25.b5 Nd8 26.a4 Nf6 27.Rh8 Kd7 28.a5
36/58 07:05 21.578.992k 50.694k +0,74 6.Bb3 d6 7.d3 Qe8 8.Nf3 Bg4 9.Be3 Qg6 10.Bxc5 dxc5 11.Nbd2 Raf8 12.h3 Bxf3 13.Qxf3 Nd4 14.Qe3 Qxg2 15.0-0-0 Nd7 16.Rhg1 Qxf2 17.Rxg7+ Kd8 18.Qg5+ Qf6 19.Qg4 Nxb3+ 20.axb3 Rf7 21.Rg5 h6 22.Rf5 Qe7 23.Rdf1 Rhf8 24.Qh5 Rf6 25.Nc4 R8f7 26.Ne3 Rxf5 27.Nxf5 Qg5+ 28.Qxg5+ hxg5
37/58 12:22 37.959.555k 51.129k +0,69 6.Bb3 d6 7.d3 Qe8 8.Nf3 Bg4 9.Be3 Qg6 10.Bxc5 dxc5 11.Nbd2 Raf8 12.h3 Bxf3 13.Qxf3 Nd4 14.Qe3 Qxg2 15.0-0-0 Nd7 16.Rhg1 Qxf2 17.Rxg7+ Kd8 18.Qg5+ Qf6 19.Qg4 Nxb3+ 20.axb3 Rf7 21.Rg5 h6 22.Rf5 Qe7 23.Rdf1 Rhf8 24.Qg6 Rf6 25.Rxf6 Rxf6 26.Rxf6 Qxf6 27.Qg8+ Qf8
38/58 20:07 61.030.518k 50.563k +0,81 6.Bc4 Qe8 7.Nc3 h6 8.Nf3 d6 9.Be2 Be6 10.d3 a6 11.Be3 Bxe3 12.fxe3 Qg6 13.Qd2 Rae8 14.0-0-0 Kd8 15.h3 h5 16.Rdg1 Kc8 17.a3 Kb8 18.Rf1 Rhf8 19.Kb1 Nd8 20.Qe1 Qh6 21.Qg3 Nf7 22.Nh4 g5 23.Qf3 Nxe4 24.Nxe4 gxh4 25.Nf6 Ng5 26.Qxh5 Qxh5 27.Bxh5
39/59 23:41 72.184.234k 50.769k +0,82 6.Bc4 Qe8 7.Nc3 h6 8.Nf3 d6 9.0-0 Kd8 10.Be2 Nd4 11.d3 Nxe2+ 12.Qxe2 Qh5 13.Be3 Bg4 14.h3 Bxf3 15.Qxf3 Qxf3 16.gxf3 Nh5 17.Ne2 g5 18.c3 Nf4 19.Bxf4 gxf4 20.d4 Bb6 21.Kh2 Ke7 22.h4 Rhg8 23.a4 a5 24.Rg1 h5 25.Rg5 Rxg5 26.hxg5 Rg8 27.Rg1 Kf7 28.Kh3 c5
40/59 25:21 77.405.622k 50.860k +0,81 6.Bc4 Qe8 7.Nc3 h6 8.Nf3 d6 9.0-0 Kd8 10.Be2 Nd4 11.d3 Nxe2+ 12.Nxe2 Rf8 13.c3 Bb6 14.Ng3 Nh5 15.Nf5 a5 16.Be3 Ra6 17.Kh1 Qf7 18.N3h4 Nf6 19.Bxb6 Rxb6 20.b3 Bd7 21.Ne3 Kc8 22.c4 Ra6 23.Nf3 g5 24.Rc1 Qh5 25.c5 g4 26.Ng1 dxc5 27.Rxc5
41/59 30:49 93.429.569k 50.530k +0,83 6.Bc4 Rf8 7.d3 d6 8.Nf3 Qe8 9.Be3 Qg6 10.Nbd2 Bg4 11.a4 Bxe3 12.fxe3 Bd7 13.Qe2 Rae8 14.h3 Kd8 15.0-0-0 Qg3 16.Rhg1 Kc8 17.b3 a6 18.Qe1 Qxe1 19.Rdxe1 Na5 20.Kb2 h6 21.Ra1 g5 22.Bb5 c6 23.b4 cxb5 24.axb5 Kc7 25.bxa5 axb5 26.a6 g4 27.hxg4 Nxg4 28.a7 Nxe3
42/59 40:50 122.686.199k 50.067k +0,89 6.Bc4 Qe8 7.Nc3 h6 8.Nf3 Kd8 9.d3 d6 10.h3 a5 11.Bb5 Qg6 12.Bxc6 bxc6 13.Nh4 Qf7 14.Qf3 Rf8 15.0-0 Be6 16.Be3 Nd7 17.Qxf7 Rxf7 18.Bxc5 Nxc5 19.Kh2 Kd7 20.Nf3 g5 21.Nd2 Rff8 22.Ne2 Ke7 23.f3 Nd7 24.Nc4 Rab8 25.b3 Bxc4 26.dxc4 c5 27.Nc3 c6 28.Rae1
43/59 53:47 159.222.530k 49.334k +0,88 6.Bc4 Qe8 7.Nc3 h6 8.Nf3 Rf8 9.Be2 Kf7 10.0-0 Kg8 11.d3 d6 12.Na4 Bb6 13.Nxb6 axb6 14.Be3 d5 15.exd5 Nxd5 16.Nd2 Bf5 17.Bf3 Rd8 18.a3 Qf7 19.Re1 Bg6 20.h3 Nce7 21.a4 Nc6 22.Qe2 Rfe8 23.Bxd5 Qxd5 24.Qg4 Qe6 25.Qxe6+ Rxe6 26.f3 Nb4 27.Rec1 Nc6 28.Bf2 Rf6 29.Bg3 Rff8
44/62 1:32:13 269.976.157k 48.789k +0,97 6.Bc4 Qe8 7.Nc3 h6 8.Nf3 d6 9.0-0 Rf8 10.Be2 Be6 11.d3 Bb6 12.Na4 Kf7 13.Nxb6 axb6 14.Be3 d5 15.exd5 Nxd5 16.Nd2 Kg8 17.Bf3 Rd8 18.a3 Bf5 19.h3 Nf6 20.Qe2 Qf7 21.Rfe1 Nd5 22.Kh1 Bg6 23.Rac1 Rfe8 24.Kg1 Nf4 25.Qd1 Nd5 26.Bxd5 Qxd5 27.Qg4 Qf7 28.f3 Rf8
45/66 2:05:20 375.419.320k 49.921k +0,93 6.Bc4 Qe8 7.Nc3 h6 8.Nf3 d6 9.0-0 Rf8 10.Be2 Be6 11.d3 Kf7 12.Na4 Kg8 13.Nxc5 dxc5 14.Be3 b6 15.Bd2 a5 16.a4 Rd8 17.b3 Bf7 18.Kh1 Qe7 19.Rc1 Qe6 20.h3 Qe7 21.Kh2 Be6 22.Kg1 Bf7 23.Ra1 Be6 24.Kh1 Bf7 25.Kh2 Bg6 26.Rh1 Be8 27.Re1 Bf7 28.Rg1 Bg6 29.Nh4 Bh7
46/66 2:06:39 379.603.214k 49.950k +0,93 6.Bc4 Qe8 7.Nc3 h6 8.Nf3 d6 9.0-0 Rf8 10.Be2 Be6 11.d3 Kf7 12.Na4 Kg8 13.Nxc5 dxc5 14.Be3 b6 15.Bd2 a5 16.a4 Rd8 17.b3 Bf7 18.Kh1 Qe7 19.Rc1 Qe6 20.h3 Qe7 21.Kh2 Be6 22.Kg1 Bf7 23.Ra1 Be6 24.Re1 Qf7 25.Kh2 Nd7 26.Kh1 Qe7 27.Rf1 Nd4 28.Nxd4 cxd4 29.f4 exf4
47/66 2:09:06 387.424.594k 50.012k +0,93 6.Bc4 Qe8 7.Nc3 h6 8.Nf3 d6 9.0-0 Rf8 10.Be2 Be6 11.d3 Kf7 12.Na4 Kg8 13.Nxc5 dxc5 14.Be3 b6 15.Bd2 a5 16.a4 Rd8 17.b3 Bf7 18.Kh1 Qe7 19.Rc1 Qe6 20.h3 Qe7 21.Kh2 Be6 22.Kg1 Bf7 23.Ra1 Be6 24.Re1 Qf7 25.Kh2 Nd7 26.Kh1 Qe7 27.Rf1 Nf6 28.Kg1 Bf7 29.Kh2 Be6 30.Nh4 Qe8 31.Re1
48/66 2:17:51 415.357.698k 50.215k +0,93 6.Bc4 Qe8 7.Nc3 h6 8.Nf3 d6 9.0-0 Rf8 10.Be2 Be6 11.d3 Kf7 12.Na4 Kg8 13.Nxc5 dxc5 14.Be3 b6 15.Bd2 a5 16.Bc3 Bf7 17.a4 Rd8 18.Qe1 Nd7 19.b3 Be6 20.h3 Qg6 21.Kh2 Qf6 22.Bd2 Qe7 23.Kg1 Rf6 24.Nh2 Nd4 25.Qd1 Rff8 26.Bg4 Bf7 27.Rc1 Nf6 28.Be2 Nc6 29.Ng4 Nxg4 30.Bxg4 Nd4 31.Be3 Bg6
49/66 2:37:05 477.474.103k 50.655k +0,93 6.Bc4 Qe8 7.Nc3 h6 8.Nf3 d6 9.0-0 Rf8 10.Be2 Be6 11.d3 Kf7 12.Na4 Kg8 13.Nxc5 dxc5 14.Be3 b6 15.b3 a5 16.Rc1 Qg6 17.a4 Rad8 18.Bd2 Qf7 19.Ra1 Qg6 20.Nh4 Qe8 21.h3 Bd7 22.Nf3 Be6 23.Kh1 Qg6 24.Nh4 Qe8 25.Kh2 Qf7 26.Rc1 Qe8 27.Nf3 Qf7 28.Re1 Qe7 29.Rg1 Nh5 30.Nxe5 Nxe5 31.Bxh5 Bxb3 32.cxb3
50/75 5:09:36 974.210.771k 52.444k +0,86 6.Bc4 Qe8 7.Nc3 Nd4 8.d3 d6 9.Ne2 Nxe2 10.Qxe2 Rf8 11.Nf3 Bg4 12.c3 Qg6 13.Be3 Bxe3 14.fxe3 Kd8 15.0-0-0 Kc8 16.Rhf1 Bd7 17.h3 Qe8 18.Nd2 h6 19.d4 Kb8 20.Bd3 a6 21.Kb1 Ka7 22.Rf2 Rd8 23.Rdf1 Kb8 24.b3 Bb5 25.Bxb5 axb5 26.g4 c6 27.Kb2 Kc7 28.Qd3 Ra8 29.a3 Rh8 30.c4 exd4 31.exd4

.