Tactical mistake by Stockfish (Grischuk-Ding at candidates)

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jp
Posts: 1320
Joined: Mon Apr 23, 2018 5:54 am

Re: Tactical mistake by Stockfish (Grischuk-Ding at candidates)

Post by jp » Fri Mar 27, 2020 5:40 pm

kiroje wrote:
Fri Mar 27, 2020 3:05 pm
Long run with Ethereal 12.00 4 threads and 8192Gb it actually finds Nf4 but get another move for white than Nf3

13.45: -0.81/39 12...Nxe5 13.Rxe5 Nf4 14.Nf3 Nxg2 15.Kxg2 a5 16.c3 Ra6 17.d4 Rg6+ 18.Kh2 Bd6 19.Nh4 a4 20.Nxg6 hxg6 21.Qg4 Qc6 22.Bf4 axb3 23.axb3 Bxe5 24.dxe5 Qe4 25.Rg1 Bc8 26.Qg3 Re8 27.b4 Qe2 28.b3 Be6 29.Be3 Bxb3 30.Qg4 Qxg4 31.hxg4 Rxe5 32.Ra1 Bc4 33.Ra7 c6 34.Bd4
37.07: -0.53/40 12...Nxe5 13.Rxe5 Nf4 14.Qg4 Qxg4 15.hxg4 Bd6 16.Re3 Nxg2 17.Re2 Nh4 18.Ne4 Nf3+ 19.Kf1 Be7 20.Bf4 Bc8 21.Nd2 Nxd2+ 22.Rxd2 Bxg4 23.Bxc7 h5 24.c3 Rac8 25.Bf4 h4 26.Re1 Rfe8 27.Bd5 g5 28.Bh2 Bf8 29.Re3 Kg7 30.Kg2 h3+ 31.Kg1 Rcd8 32.Rxe8 Rxe8 33.f3 Bf5 34.Bb7 Re3 35.Kf2 Rxd3 36.Rxd3 Bxd3 37.Bxa6 Kg6 38.Bb7 f6
Yes, but this time Ethereal did switch from 14...Nxh3+ to ... Nxg2 (with the necessary ...a5 and ...Ra6 follow-up) at depth 39, prompting it to switch White's move 14 at depth 40, so it succeeded.

And it's possible that its choice of switch, 14. Qg4, is at least as good as 14.Ne4.

SF 10 after 14.Qg4:
depth=36
-0.22 14...Qxg4 15.hxg4 Bd6 16.Re1 Nxg2 17.Re2 Nh4 18.Ne4 Nf3+ 19.Kf1 Nh2+ 20.Kg1 Nxg4 21.Nxd6 cxd6 22.Re7 Bf3 23.Bf4 d5 24.c4 dxc4 25.dxc4 bxc4 26.Bxc4 Nf6 27.Bg5 Nd5 28.Re5 h6 29.Bxd5 Bxd5 30.Rxd5 hxg5 31.Rxg5 Rfc8 32.Rd5 Rab8 33.b3 Rb4 34.Ra5 Rc2 35.Rxa6 Rg4+ 36.Kf1
depth=37
-0.53 14...Qxg4 15.hxg4 Bd6 16.Re1 Nxg2 17.Re2 Nh4 18.Ne4 Nf3+ 19.Kf1 Nh2+ 20.Kg1 Nxg4 21.Nxd6 cxd6 22.Re7 Bf3 23.Bf4 d5 24.c4 dxc4 25.dxc4 bxc4 26.Bxc4 Nf6 27.Bg5 Bd5 28.b3 Bxc4 29.bxc4 Rac8 30.Bxf6 gxf6 31.Rc1 Rc6 32.Kg2 Rfc8 33.Re4 f5 34.Rh4 Kg7 35.Kf3 Rc5 36.Rg1+ Kf6 37.Rxh7 Rxc4 38.Rh6+ Ke5 39.Rxa6

Komodo 13.2 after 14.Qg4:
depth=33
-0.65 14...Qxg4 15.hxg4 Bd6 16.Re1 Nxg2 17.Re2 Nf4 18.Re1 Bb4 19.a3 Ba5 20.Kf1 Kh8 21.Re5 Ng6 22.Rf5 Bb6 23.Bd5 c6 24.Be4 Bc8 25.Bxc6 Ra7 26.Be4 Bxf5 27.gxf5 Ne7 28.a4 g6 29.f6 Ng8 30.axb5 axb5 31.Rxa7 Bxa7 32.Bc6
depth=34
-0.51 14...Qxg4 15.hxg4 Bd6 16.Re1 Nxg2 17.Re2 Nf4 18.Re1 Bb4 19.a3 Ba5 20.Kf1 Kh8 21.Re5 Bb6 22.Rf5 Ng6 23.a4 Ne7 24.Rh5 f5 25.g5 Ng6 26.Nb1 Ne5 27.Nc3 Bf3 28.Rh3 Bg4 29.Rh1 c6 30.Ne2 Rae8 31.Be3 Bxe3 32.fxe3 Nf7 33.Bxf7

jp
Posts: 1320
Joined: Mon Apr 23, 2018 5:54 am

Re: Tactical mistake by Stockfish (Grischuk-Ding at candidates)

Post by jp » Fri Mar 27, 2020 6:59 pm

SF10 after 14.Ne4:

depth=36
-0.84 14...Ng6 15.Rxe7 Qxe7 16.Be3 Bxe4 17.dxe4 Rfd8 18.Qg4 Ne5 19.Bg5 Nxg4 20.Bxe7 Re8 21.Bh4 Ne5 22.f3 Nc4 23.Rd1 Nxb2 24.Rd7 Nc4 25.Rxc7 Rec8 26.Re7 a5 27.a4 bxa4 28.Bxa4 h5 29.Be1 f6 30.Bf2 Nd2 31.e5 Rab8 32.exf6 gxf6 33.Be3 Rc4 34.Bxd2 Rxa4 35.Ra7 Ra1+ 36.Kh2 Ra2 37.Rxa5 Rxc2
depth=37
-0.61 14...Ng6 15.Rxe7 Qxe7 16.Be3 Bxe4 17.dxe4 Rfd8 18.Qg4 Ne5 19.Bg5 Nxg4 20.Bxe7 Re8 21.Bh4 Ne5 22.f3 c6 23.Be1 h6 24.Bc3 a5 25.a4 b4 26.Bd4 Kh7 27.Bxe5 Rxe5 28.Rd1 Ra7 29.Kf1 Re8 30.Rd6 Rc7 31.Bc4 h5 32.Kf2 h4 33.Bd3 Re5 34.Rd8 Rc5 35.Ra8
depth=38
-0.79 14...Ng6 15.Rxe7 Qxe7 16.Be3 Bxe4 17.dxe4 Rfd8 18.Qg4 Ne5 19.Bg5 Nxg4 20.Bxe7 Re8 21.Bh4 Ne5 22.f3 c6 23.Be1 Nd7 24.Bf2 h6 25.a4 Red8 26.Kh2 g6 27.c3 Ne5 28.Bd4 Nc4 29.Ra2 a5 30.Kg1 Rd7 31.axb5 cxb5 32.Kf2 a4 33.Bxc4 bxc4

Komodo 13.2 after 14.Ne4:

depth=36
-0.69 14...Ng6 15.Rxe7 Qxe7 16.Be3 Bxe4 17.dxe4 Rfe8 18.a4 Rad8 19.Qf3 Ne5 20.Qe2 Qb4 21.axb5 axb5 22.f3 Ra8 23.Rc1 Nc4 24.Bxc4 Qxc4 25.Qxc4 bxc4 26.Bd4 f6 27.Bc3 Kf7 28.Kf2 Ke6 29.Re1 g5 30.e5 f5 31.Ke3 c6 32.Kd4 Red8+ 33.Kxc4 Ra6 34.g4
depth=37
-0.69 14...Ng6 15.Rxe7 Qxe7 16.Be3 Bxe4 17.dxe4 Rad8 18.Qg4 Kh8 19.a4 Rfe8 20.axb5 axb5 21.Qh5 Ne5 22.Qe2 c6 23.Re1 Qb4 24.f3 Rd7 25.Ra1 Nc4 26.Bxc4 bxc4 27.Ra6 c3 28.Qe1 Qxb2 29.Rxc6 Qxc2 30.Qxc3 Rd1+ 31.Kh2 Qxc3 32.Rxc3 Red8 33.Kg3 Kg8 34.Rc7 R1d7 35.Rxd7


SF10 after 14.Nf3:

depth=36
-0.32 14...Nxg2 15.Kxg2 a5 16.c3 Ra6 17.d4 Rg6+ 18.Kh2 Bd6 19.Nh4 a4 20.Nxg6 hxg6 21.Qg4 Qxg4 22.hxg4 axb3 23.Kh3 f6 24.Re6 Ra8 25.a3 Kf7 26.Rxd6 cxd6 27.Bf4 Ke6 28.g5 Kd7 29.Kg3 Bc6 30.f3 Rh8 31.Be3 Rh5 32.d5 Bxd5 33.a4 bxa4 34.Rxa4 fxg5
depth=37
-0.32 14...Nxg2 15.Kxg2 a5 16.c3 Ra6 17.d4 Rg6+ 18.Kh2 a4 19.Bc2 Bd6 20.Bf4 Rf6 21.Qd2 Bxf3 22.Qd3 g6 23.Qxf3 Rxf4 24.Qxf4 f6 25.Qe3 fxe5 26.dxe5 Bxe5+ 27.Kg2 Bf4 28.Qc5 Qd2 29.Be4 Kg7 30.Bf3 Rf5 31.Qd4+ Qxd4 32.cxd4 Bg5 33.Bc6 Bh4 34.Rf1 Kh6 35.a3 Rf4 36.Bxb5 Rxd4 37.Kf3 Rd2 38.Bxa4 Bg5 39.Bc6 Rxb2

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