About 10% of the WCSAC EPD positions are broken.

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Dann Corbit
Posts: 12540
Joined: Wed Mar 08, 2006 8:57 pm
Location: Redmond, WA USA

About 10% of the WCSAC EPD positions are broken.

Post by Dann Corbit »

Analysis of the WCSAC positions shows a large number that are clearly broken. Many of the positions below have a clear checkmate that is not the suggested best move. On many of them, I watched the supposed best move get chosen and then quickly abandoned for something else.
I guess that in 20 or so of the positions below, Rybka simply did not search deep enough or for some other reasons missed the best move.

My 1st question is, for the following positions, are there any engines that both get the key move and also get a better score than the one that Rybka found?

My second question is, for the following positions, are there any that are clearly correct even though no computer program can find it?
  • rn3rk1/ppp3pp/4bq2/2b1Np2/2B2P2/8/PPP1Q1PP/R1B1K2R w KQ - bm Nd7; id "wcsac.0018"; acd 17; acs 53; acn 8268768; ce 24; pm Bc1d2; pv Bc1d2 Rf8e8 OOO Nb8a6 Kc1b1 Be6xc4 Qe2xc4+ Qf6e6 Qc4b5 Bc5b6 Rh1e1 Na6c5 Bd2b4 c7c6; c0 "Analyzing engine: Rybka v1.2.w32";
    2b5/1p3r2/p1p2rk1/P1Pp1pp1/3P2P1/4P2P/2B1K3/1R3R2 w - - bm gxf5+; id "wcsac.0027"; acd 21; acs 18; acn 13739320; ce 53; pm Ke2d2; pv Ke2d2 Rf7h7 Rf1f3 Rh7f7 Kd2c3 Rf7e7 Rb1g1 Re7g7 Bc2d3 Rg7h7 Rf3g3 Kg6f7 Rg1f1 Kf7g6; c0 "Analyzing engine: Rybka v1.2.w32";
    4rrk1/ppp1qppp/5n2/2b1n1N1/2B3b1/1QN5/PB4PP/4RR1K w - - bm Bxf7+; id "wcsac.0037"; acd 16; acs 36; acn 4926408; ce 231; pm Nc3d5; pv Nc3d5 Nf6xd5 Re1xe5 Qe7xe5 Bb2xe5 Re8xe5 Ng5xf7 Re5e3 Qb3b5 Bg4e6 Bc4xd5 b7b6 Bd5xe6 Re3xe6; c0 "Analyzing engine: Rybka v1.2.w32";
    r2q1r2/pb2bpkp/1p2pnp1/nP2Q3/6N1/P2B2N1/1BP2PPP/R4RK1 w - - bm Nxf6; id "wcsac.0040"; acd 14; acs 32; acn 4903480; ce 629; pm Ng3h5+; pv Ng3h5+ Kg7h8 Nh5xf6 Na5b3 c2xb3 Qd8xd3 Nf6d5+ f7f6 Nd5xe7 Kh8g7 Ng4xf6 Kg7f7 Ne7g8 Bb7c8; c0 "Analyzing engine: Rybka v1.2.w32";
    3qk2r/1pp1nppp/1p6/r7/8/5Q2/PP3PPP/R1B1R1K1 w - - bm Bg5; id "wcsac.0053"; acd 18; acs 24; acn 11142976; ce 253; pm Bc1h6; pv Bc1h6 g7xh6 Ra1d1 Qd8xd1 Re1xd1 Rh8g8 Qf3xb7 f7f6 Qb7xc7 Ke8f7 Rd1e1 Rg8e8 Qc7c4+ Kf7g7; c0 "Analyzing engine: Rybka v1.2.w32";
    r2q2k1/pp5p/4b1pQ/3Nn3/8/6PP/P5B1/3R2K1 w - - bm Qe3; id "wcsac.0054"; acd 18; acs 27; acn 9654488; ce 307; pm Qh6f4; pv Qh6f4 Ne5d7 Nd5c7 Qd8f8 Qf4xf8+ Ra8xf8 Nc7xe6 Rf8f7 Bg2xb7 Rf7e7 Bb7d5 Nd7b6 Rd1f1 h7h5; c0 "Analyzing engine: Rybka v1.2.w32";
    r1bq1rk1/pp2bp1p/2p2np1/3p2B1/3P4/2NQ2N1/PPP2PPP/4RRK1 w - - bm Rxe7; id "wcsac.0062"; acd 14; acs 53; acn 3185624; ce 32; pm f2f4; pv f2f4 Be7d6 f4f5 Kg8g7 Qd3e3 Kg7g8 Qe3f3 Kg8g7 Rf1f2 h7h6 Bg5f4 Qd8c7 Bf4xd6; c0 "Analyzing engine: Rybka v1.2.w32";
    6rk/1b4rp/2q2n2/p1n5/4p2Q/1PN2N2/PBP1R3/K3R3 w - - bm Nxe4; id "wcsac.0071"; acd 14; acs 58; acn 6989216; ce 275; pm Nf3g5; pv Nf3g5 Rg7xg5 Nc3xe4 Nc5xe4 Re2xe4 Rg5g6 Re4e6 Rg8f8 Re6xc6 Bb7xc6 Re1f1 Kh8g7 Bb2xf6+ Rf8xf6; c0 "Analyzing engine: Rybka v1.2.w32";
    rnbqk2r/pppp1ppp/5n2/2bPp1B1/2P5/8/PP2PPPP/RN1QKBNR b KQkq - bm Ne4; id "wcsac.0080"; acd 17; acs 59; acn 11308144; ce 62; pm Bc5xf2+; pv Bc5xf2+ Ke1xf2 Nf6g4+ Kf2e1 Qd8xg5 Qd1d2 Qg5e3 Qd2xe3 Ng4xe3 Nb1a3 f7f5 Ng1f3 d7d6 Ke1f2; c0 "Analyzing engine: Rybka v1.2.w32";
    2r3k1/2rb1pp1/5n1p/q1BPp3/p3Pn2/2R4P/2Q2PPK/1NR2B2 b - - bm N4xd5; id "wcsac.0084"; acd 18; acs 55; acn 9414992; ce 97; pm Nf6xe4; pv Nf6xe4 Qc2xe4 Rc7xc5 Qe4xe5 Nf4xd5 Rc3xc5 Rc8xc5 Rc1xc5 Qa5xc5 Nb1a3 Qc5c7 Qe5xc7 Nd5xc7 Kh2g3; c0 "Analyzing engine: Rybka v1.2.w32";
    6k1/p4p2/1p2p1p1/4P3/PP2bP2/2B1b2p/6PP/6RK b - - bm Kh7; id "wcsac.0097"; acd 24; acs 44; acn 43393856; ce 517; pm Kg8g7; pv Kg8g7 Bc3b2 Kg7h6 f4f5 g6xf5 Bb2c1 h3xg2+ Rg1xg2 Be3xc1 h2h4 Be4xg2+ Kh1xg2 Bc1f4 b4b5; c0 "Analyzing engine: Rybka v1.2.w32";
    r5k1/pp4p1/6r1/3p4/2nPNpPq/2P4P/P3Q2K/1R4R1 b - - bm Re6; id "wcsac.0107"; acd 17; acs 47; acn 12361368; ce 275; pm Qh4e7; pv Qh4e7 Rb1e1 Qe7c7 Ne4g3 f4xg3+ Rg1xg3 Rg6b6 Qe2f3 Ra8d8 Re1e2 Rb6f6 Qf3g2 Qc7d6 h3h4; c0 "Analyzing engine: Rybka v1.2.w32";
    r3rk2/5ppQ/np1bbq1p/p1ppN3/3P4/P1N1P3/1P3PPP/1BR2RK1 w - - bm Nxd5; id "wcsac.0119"; acd 16; acs 6; acn 8480448; ce 353; pm Ne5d7+; pv Ne5d7+ Kf8e7 Nd7xf6 g7xf6 Qh7xh6 Re8h8 Bb1h7 Na6c7 d4xc5 b6xc5 e3e4 d5d4 Nc3a4 Nc7a6; c0 "Analyzing engine: Rybka v1.2.w32";
    r4b1r/pp1k1ppp/5p2/3N4/3pq3/8/PPP2QPP/2KR3R w - - bm Nxf6+; id "wcsac.0133"; acd 17; acs 19; acn 6093400; ce 349; pm Rd1xd4; pv Rd1xd4 Qe4e5 Nd5b6+ Kd7e6 Nb6xa8 Bf8c5 Na8c7+ Ke6e7 Rh1e1 Bc5xd4 Re1xe5+ Bd4xe5 Nc7d5+ Ke7e6; c0 "Analyzing engine: Rybka v1.2.w32";
    5r2/6p1/PNk5/2N1p2p/1PP5/6P1/6K1/8 w - - bm b5+; id "wcsac.0139"; acd 18; acs 30; acn 2931448; ce 1351; pm Nb6d7; pv Nb6d7 Rf8a8 b4b5+ Kc6d6 b5b6 Kd6c6 b6b7 Ra8d8 a6a7 Rd8xd7 a7a8Q Rd7xb7 Nc5xb7 Kc6b6; c0 "Analyzing engine: Rybka v1.2.w32";
    8/p2r2pk/2q2p1p/2P1p1n1/4P3/6P1/PBQ4P/1R4K1 b - - bm Rd2; id "wcsac.0157"; acd 19; acs 41; acn 19923688; ce 1025; pm Ng5f3+; pv Ng5f3+ Kg1f2 Rd7d2+ Qc2xd2 Nf3xd2 Rb1e1 Qc6xc5+ Kf2e2 Qc5c2 Bb2c1 Nd2xe4+ Ke2f3 Qc2f2+ Kf3xe4; c0 "Analyzing engine: Rybka v1.2.w32";
    r1b1r1k1/ppp2ppp/3B4/8/2P1N1P1/P1np3P/1P3P2/R3KB1R b KQ - bm d2+; id "wcsac.0158"; acd 20; acs 39; acn 18590464; ce 270; pm Nc3xe4; pv Nc3xe4 Bf1xd3 Ne4g3+ Ke1d2 Ng3xh1 Bd6c5 b7b6 Bc5xb6 c7xb6 Ra1xh1 Bc8b7 Rh1g1 Re8e6 g4g5; c0 "Analyzing engine: Rybka v1.2.w32";
    2r3k1/1p3pBp/8/qN1p4/3Qn3/P3PB2/2rnRPPb/R2K4 b - - bm Rc1+; id "wcsac.0162"; acd 59; acs 50; acn 12458968; ce 32756; pm Qa5xb5; pv Qa5xb5 Qd4c5 Rc8xc5 Bg7c3 Ne4xc3+ Kd1xc2 Nc3b1+ Kc2d1 Qb5b3+ Kd1e1 Rc5c1; c0 "Analyzing engine: Rybka v1.2.w32";
    2r2rk1/pp1b2pp/4pb2/q1np4/7P/P1NB1N2/1PPQ1PP1/2K1R2R b - - bm d4; id "wcsac.0169"; acd 16; acs 18; acn 7549432; ce 249; pm Nc5xd3+; pv Nc5xd3+ Qd2xd3 Bf6xc3 Re1e3 e6e5 b2xc3 e5e4 Qd3d4 e4xf3 Re3xf3 Rf8xf3 g2xf3 Rc8xc3 Rh1d1; c0 "Analyzing engine: Rybka v1.2.w32";
    8/1Q2ppk1/6p1/2qN4/p1r3n1/6P1/P5KP/5R2 b - - bm Qxd5+; id "wcsac.0180"; acd 23; acs 50; acn 27360136; ce 32746; pm Rc4c2+; pv Rc4c2+ Kg2h3 f7f5 Rf1xf5 g6xf5 Kh3h4 Ng4e5 Kh4g5 Ne5f7+ Kg5xf5 Qc5d4 Qb7xe7 Qd4xd5+ Kf5g4 Rc2c4+ Kg4h3 Qd5f5+ Kh3g2 Rc4c2+ Kg2g1 Qf5f2+ Kg1h1 Qf2xh2; c0 "Analyzing engine: Rybka v1.2.w32";
    r3rbk1/3n1pp1/2N4p/2pP4/qpN2B2/5Q2/1P3PPP/2RR2K1 w - - bm Bxh6; id "wcsac.0195"; acd 16; acs 4; acn 6988080; ce 336; pm Qf3h3; pv Qf3h3 Ra8a7 Bf4d6 Qa4a2 Nc6xa7 Qa2xa7 Rc1a1 Qa7b7 Nc4a5 Qb7b5 Bd6xf8 Nd7xf8 Na5c6 Qb5e2; c0 "Analyzing engine: Rybka v1.2.w32";
    r5k1/1p1P1p1p/p1q2bp1/1N3n2/8/1P4PB/P2Q1P2/4R1K1 w - - bm Na7; id "wcsac.0201"; acd 19; acs 13; acn 9744792; ce 342; pm Re1c1; pv Re1c1 a6xb5 Rc1xc6 b7xc6 Bh3xf5 g6xf5 Qd2h6 Bf6e7 Qh6xc6 Ra8d8 Qc6xb5 Kg8f8 Qb5xf5 Be7d6; c0 "Analyzing engine: Rybka v1.2.w32";
    r2b1r1k/p4bR1/1p3P2/n2p3p/2pP1Bp1/2Pq2N1/PP2Q1PP/R5K1 w - - bm Rxf7; id "wcsac.0204"; acd 17; acs 22; acn 9267744; ce 391; pm Qe2e5; pv Qe2e5 Rf8g8 Rg7xf7 Qd3g6 Qe5xd5 h5h4 Rf7g7 Rg8xg7 f6xg7+ Kh8h7 Qd5xa8 h4xg3 Qa8xd8 g3xh2; c0 "Analyzing engine: Rybka v1.2.w32";
    rn2kb1r/p3pppp/b4n2/3qN3/2pP4/4P3/5PPP/RNBQKB1R w KQkq - bm Rxa6; id "wcsac.0210"; acd 17; acs 2; acn 4137600; ce 231; pm Nb1c3; pv Nb1c3 Qd5b7 Ra1xa6 e7e6 Ra6a1 Bf8b4 Bc1d2 Nb8d7 Ne5xc4 OO Ra1b1 Ra8b8 Qd1a4 Rf8c8; c0 "Analyzing engine: Rybka v1.2.w32";
    8/3qNrpk/1bpnRpNp/pp1p1P2/3P2P1/P1P4P/1P2Q1K1/8 w - - bm Nxd5; id "wcsac.0216"; acd 17; acs 26; acn 8796024; ce 239; pm g4g5; pv g4g5 f6xg5 Ng6e5 Qd7xe7 Re6xe7 Rf7xe7 Qe2h5 Kh7g8 Qh5g6 Nd6e8 Qg6xc6 Bb6c7 Ne5g6 Re7e3; c0 "Analyzing engine: Rybka v1.2.w32";
    r1bq1rk1/pppn1ppp/5n2/4p3/1bBP4/2N1P3/PP2NPPP/R1BQ1RK1 w - - bm Bxf7+; id "wcsac.0226"; acd 15; acs 44; acn 8422800; ce 09; pm a2a3; pv a2a3 Bb4e7 Qd1c2 Nd7b6 Bc4a2 e5xd4 Ne2xd4 c7c5 Nd4f5 c5c4 Rf1d1 Bc8xf5 Qc2xf5 Be7d6; c0 "Analyzing engine: Rybka v1.2.w32";
    1rq2n2/1pp2kbr/p1n1p1pp/2N1P3/5P2/1Q2B2B/PP3P1P/2RR2K1 w - - bm Bxe6+; id "wcsac.0234"; acd 18; acs 25; acn 9736296; ce 743; pm Nc5xe6; pv Nc5xe6 Nf8xe6 Bh3xe6+ Qc8xe6 Rd1d7+ Kf7g8 Qb3xe6+ Kg8h8 Qe6b3 Rb8g8 Qb3xb7 Nc6d8 Qb7d5 c7c6; c0 "Analyzing engine: Rybka v1.2.w32";
    4Q3/8/2r3pk/3b4/1PpP2P1/8/7P/6K1 w - - bm Qh8+; id "wcsac.0244"; acd 22; acs 45; acn 16235944; ce 1093; pm h2h4; pv h2h4 Kh6h7 Qe8d7+ Kh7h8 b4b5 Rc6e6 Qd7xd5 Re6e1+ Kg1f2 Re1e8 Qd5e5+ Re8xe5 d4xe5 c4c3; c0 "Analyzing engine: Rybka v1.2.w32";
    2r1r1k1/1p1qbp1p/3p1p2/p2P4/3Q4/5N2/PP2RPPP/4R1K1 w - - bm Rxe7; id "wcsac.0247"; acd 17; acs 30; acn 11537544; ce 86; pm b2b3; pv b2b3 Be7f8 Re2xe8 Rc8xe8 Re1xe8 Qd7xe8 Qd4xf6 h7h6 Qf6f4 Qe8b5 Qf4e4 Bf8g7 g2g3 Qb5c5; c0 "Analyzing engine: Rybka v1.2.w32";
    r2r2k1/ppb1qpp1/2n2n1p/2P1p3/1P1p4/P3PN2/1BQ1NPPP/3RK2R b K - bm d3; id "wcsac.0253"; acd 16; acs 16; acn 5943488; ce 54; pm d4xe3; pv d4xe3 Rd1xd8+ Ra8xd8 f2xe3 Nf6d5 Bb2c1 e5e4 Nf3d4 a7a5 b4b5 Nc6e5 Qc2xe4 Qe7xc5 OO; c0 "Analyzing engine: Rybka v1.2.w32";
    1r1r2k1/3q1pbp/1n4p1/2R5/p3Q3/4NP1P/P2N2P1/3R3K b - - bm Re8; id "wcsac.0261"; acd 17; acs 46; acn 11110680; ce 60; pm f7f5; pv f7f5 Qe4f4 Qd7d6 Qf4xd6 Rd8xd6 Ne3f1 Rb8e8 Rd1b1 Re8e2 a2a3 Bg7d4 Rc5c7 Rd6d8 Rb1b4; c0 "Analyzing engine: Rybka v1.2.w32";
    r1r3k1/1p1bqppp/5n2/pP1Pp2N/4n3/P2QP3/1B2BPPP/R3K2R b KQ - bm Nxf2; id "wcsac.0265"; acd 17; acs 58; acn 11720288; ce 16; pm Bd7f5; pv Bd7f5 Nh5xf6+ Qe7xf6 OO Ne4c3 Qd3xc3 Rc8xc3 Bb2xc3 Qf6d6 Rf1d1 g7g5 Ra1c1 Ra8c8 Bc3b2; c0 "Analyzing engine: Rybka v1.2.w32";
    1k1r1q2/pnp2p1p/1p2pp2/r7/2PP1P2/3R2P1/PKP1Q1NP/7R b - - bm Rxd4; id "wcsac.0266"; acd 17; acs 58; acn 6468280; ce 146; pm Qf8b4+; pv Qf8b4+ Rd3b3 Qb4a4 a2a3 Rd8xd4 Rh1d1 Rd4xc4 Ng2e3 Rc4e4 Kb2c1 Ra5d5 Qe2f2 Rd5xd1+ Ne3xd1; c0 "Analyzing engine: Rybka v1.2.w32";
    3R4/pkp4p/8/4p3/1q1n4/3R2P1/1N5P/2K5 b - - bm Qe1+; id "wcsac.0272"; acd 20; acs 38; acn 16913272; ce 324; pm a7a5; pv a7a5 Kc1b1 a5a4 Kb1a2 Nd4e2 Rd3e3 Ne2c3+ Re3xc3 Qb4xc3 Rd8d3 Qc3c5 Nb2xa4 Qc5c2+ Na4b2; c0 "Analyzing engine: Rybka v1.2.w32";
    7k/p1p1r1p1/1b5p/4B2q/5P2/6P1/P1Q4P/R3K3 b - - bm Rxe5+; id "wcsac.0275"; acd 20; acs 40; acn 14047000; ce 1012; pm Qh5f3; pv Qh5f3 Qc2d2 Re7d7 Qd2xd7 Bb6a5+ Qd7d2 Qf3e3+ Ke1f1 Qe3xd2 Ra1b1 Qd2d3+ Kf1g2 Qd3xb1 a2a3; c0 "Analyzing engine: Rybka v1.2.w32";
    6k1/1bp3pp/1p1p4/p3p2r/P1P2r2/1P1Q1PqP/2P3P1/3R1RBK b - - bm Rxf3; id "wcsac.0289"; acd 21; acs 39; acn 16021336; ce 1005; pm Rh5xh3+; pv Rh5xh3+ g2xh3 Qg3xh3+ Bg1h2 Rf4xf3 Qd3xf3 Bb7xf3+ Rf1xf3 Qh3xf3+ Kh1g1 Qf3xd1+ Kg1g2 Qd1xc2+ Kg2g1; c0 "Analyzing engine: Rybka v1.2.w32";
    r1b1k2r/pp1nppbp/1qnp2p1/4P3/3N1P2/2N1B3/PPP1B1PP/R2QK2R w KQkq - bm Ne6; id "wcsac.0296"; acd 16; acs 20; acn 4382680; ce 87; pm Nd4f5; pv Nd4f5 Qb6xb2 Nf5xg7+ Ke8f8 Nc3b5 Qb2b4+ Be3d2 Qb4c5 Ng7e8 Kf8xe8 Nb5c7+ Ke8f8 Nc7xa8 d6xe5; c0 "Analyzing engine: Rybka v1.2.w32";
    4n1k1/rrp1q1pp/5p2/R3pb2/1P6/2Q1PP2/1B2B1PP/2R3K1 w - - bm Ba6; id "wcsac.0300"; acd 17; acs 33; acn 8740016; ce 141; pm Rc1a1; pv Rc1a1 c7c6 Qc3a3 Ra7xa5 b4xa5 c6c5 a5a6 Rb7a7 Ra1c1 Bf5c8 Qa3a5 Qe7d6 Qa5a4 Ne8c7; c0 "Analyzing engine: Rybka v1.2.w32";
    rn3rk1/1bB1bppp/p7/1p1P4/P1p5/3N2P1/1P3PBP/R4RK1 w - - bm d6; id "wcsac.0305"; acd 19; acs 16; acn 9421584; ce 119; pm Rf1e1; pv Rf1e1 Be7d8 Nd3c5 Bd8xc7 Nc5xb7 Ra8a7 a4xb5 Ra7xb7 d5d6 Bc7a5 Bg2xb7 Ba5xe1 b5xa6 Nb8xa6; c0 "Analyzing engine: Rybka v1.2.w32";
    rn1q1rk1/pbppbppp/1p2p3/8/2P5/2n2NP1/PPQPPPBP/R1B1R1K1 w - - bm Ng5; id "wcsac.0315"; acd 15; acs 52; acn 4808528; ce 15; pm d2xc3; pv d2xc3 Nb8c6 Bc1f4 d7d6 Ra1d1 Ra8b8 h2h4 h7h6 e2e4 Qd8d7 e4e5 Rf8d8 b2b4; c0 "Analyzing engine: Rybka v1.2.w32";
    2kr3r/ppp2ppp/3b4/5b1q/8/2PP1N2/PPQ2PPP/R1B2RK1 b - - bm Bxd3; id "wcsac.0341"; acd 16; acs 50; acn 14659256; ce 247; pm Bf5g4; pv Bf5g4 Nf3e5 Qh5xe5 f2f4 Qe5e2 Rf1f2 Qe2xc2 Rf2xc2 Bg4f5 Bc1e3 Rh8e8 Kg1f2 Bf5xd3 Rc2d2; c0 "Analyzing engine: Rybka v1.2.w32";
    r1b4Q/ppp2kpp/3b4/8/4RP1q/8/PPP3PP/3R2K1 b - - bm Bh3; id "wcsac.0345"; acd 24; acs 55; acn 15685520; ce 32744; pm Bd6c5+; pv Bd6c5+ Kg1h1 Bc8h3 g2xh3 Qh4xh3 Rd1d7+ Qh3xd7 Qh8xa8 Qd7d1+ Kh1g2 Qd1g1+ Kg2h3 Qg1f1+ Kh3g3 Qf1f2+ Kg3h3 Qf2f3+ Kh3h4 Bc5f2+ Kh4g5 h7h6+ Kg5f5 Qf3h5; c0 "Analyzing engine: Rybka v1.2.w32";
    3rr1k1/p4ppp/1p3q2/1P2n3/3Rn3/B3P3/B1Q2PPP/5RK1 b - - bm Nf3+; id "wcsac.0346"; acd 17; acs 21; acn 10605640; ce 356; pm Rd8xd4; pv Rd8xd4 Ba2b3 Rd4d3 Ba3b4 Re8d8 h2h3 Qf6g6 f2f4 Ne4d2 f4xe5 Nd2xb3 Qc2c7 Rd8e8 Qc7xa7; c0 "Analyzing engine: Rybka v1.2.w32";
    3rk1r1/pp3p1p/1nb1p3/8/qn2P2Q/3B1N2/PP3PPP/3R1RK1 w - - bm Qxd8+; id "wcsac.0349"; acd 18; acs 47; acn 14386000; ce 292; pm Bd3c2; pv Bd3c2 Rd8c8 Bc2xa4 Bc6xa4 Rd1c1 Ba4c6 Qh4xh7 Rg8f8 Nf3e5 Nb4a6 Rf1d1 Na6b8 Qh7h5 a7a6; c0 "Analyzing engine: Rybka v1.2.w32";
    r1b1k2r/pp1n3p/2pb3q/3pN1p1/3PpP2/2N1P3/PP4PP/R2QBRK1 w kq - bm Nf7; id "wcsac.0351"; acd 17; acs 30; acn 6522352; ce 160; pm f4xg5; pv f4xg5 Qh6e6 Qd1h5+ Ke8e7 Ne5f7 Rh8g8 Nf7xd6 Ke7xd6 Be1g3+ Kd6e7 Qh5xh7+ Ke7e8 Bg3f4 Qe6g6; c0 "Analyzing engine: Rybka v1.2.w32";
    3r4/r7/pp1p1bnk/2pP1RN1/P1P3QP/6P1/1qB2P1K/8 w - - bm Qh5+; id "wcsac.0367"; acd 41; acs 59; acn 54591944; ce 32752; pm Ng5e6; pv Ng5e6 Kh6h7 Qg4h5+ Kh7g8 Qh5xg6+ Ra7g7 Ne6xg7 b6b5 Ng7e6+ Bf6g7 Qg6f7+ Kg8h8 Rf5h5+ Bg7h6 Rh5xh6; c0 "Analyzing engine: Rybka v1.2.w32";
    2r1q1r1/pb1n1ppk/3pNn1p/2pP1P2/2p4B/P1P4R/3Q2PP/1B3RK1 w - - bm Nxg7; id "wcsac.0381"; acd 59; acs 30; acn 5920552; ce 32756; pm Bh4xf6; pv Bh4xf6 Nd7xf6 Ne6xg7 h6h5 Rh3xh5+ Nf6xh5 f5f6+ Qe8e4 Bb1xe4+ Kh7h8 Qd2h6; c0 "Analyzing engine: Rybka v1.2.w32";
    r2r2k1/p2nqpp1/2b1p2p/4B1P1/2p4Q/3B4/PPP2P1P/2KR2R1 w - - bm Qxh6; id "wcsac.0384"; acd 18; acs 4; acn 6740728; ce 850; pm Be5xg7; pv Be5xg7 Nd7f8 Bg7f6 Nf8g6 g5xh6 Kg8h7 Bd3xg6+ f7xg6 Bf6xe7 Rd8g8 Qh4f6 Bc6e8 Qf6xe6 c4c3; c0 "Analyzing engine: Rybka v1.2.w32";
    2Q5/k1p5/pb5p/6p1/3r4/p2q2BP/5PP1/2R3K1 b - - bm Qxg3; id "wcsac.0393"; acd 20; acs 19; acn 14886672; ce 1020; pm Rd4c4; pv Rd4c4 Rc1a1 Qd3xg3 Qc8f5 a3a2 Qf5f3 Qg3xf3 g2xf3 Rc4c2 Kg1h1 Bb6d4 Ra1xa2 Rc2xa2 Kh1g2; c0 "Analyzing engine: Rybka v1.2.w32";
    r4rk1/1bp3pp/p3Pp2/1pb2P1Q/5B1N/1Pq1p1PK/P6P/R2R4 w - - bm Rd7; id "wcsac.0408"; acd 16; acs 40; acn 3380256; ce 210; pm Ra1c1; pv Ra1c1 Qc3b4 Rd1d7 Bb7c6 Rd7xc7 Ra8c8 e6e7 Bc5xe7 Rc7xc6 Rc8xc6 Rc1xc6 Qb4e1 Nh4g2 Qe1d2; c0 "Analyzing engine: Rybka v1.2.w32";
    8/8/8/1p5r/p1p1k1pN/P2pBpP1/1P1K1P2/8 b - - bm b4; id "wcsac.0464"; acd 25; acs 18; acn 26422872; ce 1589; pm Rh5xh4; pv Rh5xh4 Be3g5 Rh4h1 Kd2c3 Rh1f1 Bg5e3 Rf1e1 Be3c5 Re1e2 Bc5e7 Re2c2+ Kc3b4 Rc2xb2+ Kb4c5; c0 "Analyzing engine: Rybka v1.2.w32";
    3r4/1p3k1p/p1b1p1p1/4Q1Pn/2B3KP/4pP2/PP2R1N1/6q1 b - - bm Rd4+; id "wcsac.0472"; acd 15; acs 47; acn 3559280; ce 46; pm Rd8e8; pv Rd8e8 Qe5c7+ Re8e7 Qc7e5 b7b5 Bc4b3 a6a5 a2a4 b5xa4 Bb3c4 Qg1f1 Qe5xe3 Kf7f8 Ng2f4; c0 "Analyzing engine: Rybka v1.2.w32";
    r2r2k1/pp1bpp1p/6p1/q1ppn3/6P1/1PbPPBN1/P1PN1P2/1R1QK2R b K - bm Nxf3+; id "wcsac.0473"; acd 16; acs 3; acn 4797544; ce 272; pm Bc3xd2+; pv Bc3xd2+ Ke1e2 Bd2c3 a2a4 Qa5b4 Ke2f1 Ne5xf3 Qd1xf3 Bd7xa4 g4g5 Bc3e5 Qf3g2 c5c4 Qg2h3; c0 "Analyzing engine: Rybka v1.2.w32";
    1r4k1/6pp/4N3/3r4/b7/3R4/K2R2PP/8 b - - bm Ra5; id "wcsac.0474"; acd 19; acs 49; acn 18666968; ce 298; pm Ba4b3+; pv Ba4b3+ Ka2b2 Rd5xd3 Rd2xd3 Bb3xe6+ Kb2c3 Rb8c8+ Kc3d2 Be6f5 Rd3c3 Rc8xc3 Kd2xc3 Kg8f7 Kc3c4; c0 "Analyzing engine: Rybka v1.2.w32";
    r4rk1/2p2pp1/pppb1q1p/4pN2/3PPn2/5Q1P/PPP2PP1/R1B2RK1 b - - bm exd4; id "wcsac.0475"; acd 19; acs 59; acn 15949976; ce 48; pm Nf4e6; pv Nf4e6 Nf5xh6+ Kg8h7 Qf3xf6 g7xf6 d4xe5 Bd6xe5 Nh6g4 Ne6c5 Ng4xe5 f6xe5 f2f3 Ra8d8 Bc1e3; c0 "Analyzing engine: Rybka v1.2.w32";
    rnb2r1k/pp4pp/2p1Pp2/3p1P2/4N2q/1BB5/P3Q2P/6RK w - - bm Nxf6; id "wcsac.0496"; acd 17; acs 5; acn 8011688; ce 782; pm e6e7; pv e6e7 Rf8e8 Bc3xf6 Re8xe7 Bf6xh4 Bc8xf5 Bh4xe7 Nb8d7 Ne4d6 Bf5g6 Qe2b2 Ra8b8 Bb3c2 c6c5; c0 "Analyzing engine: Rybka v1.2.w32";
    rn1qk2r/p2b3p/1p2p1p1/1B5Q/4P3/B1P1n3/P1P3PP/R4RK1 w kq - bm Qxh7; id "wcsac.0502"; acd 59; acs 2; acn 186672; ce 32760; pm Qh5e5; pv Qh5e5 Ne3f5 Rf1xf5 Qd8f6 Qe5xf6; c0 "Analyzing engine: Rybka v1.2.w32";
    r5b1/pqr3kp/1pn3p1/1Bp2pN1/4p3/2P3QP/PPPR1PP1/3R2K1 w - - bm Qxc7+; id "wcsac.0516"; acd 16; acs 6; acn 5096072; ce 266; pm Rd2d6; pv Rd2d6 f5f4 Qg3g4 Nc6d4 c3xd4 Ra8f8 d4xc5 b6xc5 Bb5c6 Qb7xb2 Bc6xe4 f4f3 Qg4h4 Kg7h8; c0 "Analyzing engine: Rybka v1.2.w32";
    r3r1k1/pb1qbp1p/1pn3pB/3N4/3pQ3/6P1/PP2PPBP/2RR2K1 w - - bm Qxe7; id "wcsac.0520"; acd 17; acs 37; acn 7095880; ce 235; pm Rc1xc6; pv Rc1xc6 Bb7xc6 Qe4xd4 f7f6 Nd5xe7+ Qd7xe7 Bg2xc6 Ra8d8 Bc6d5+ Kg8h8 Bh6f4 Rd8c8 Kg1g2 Re8d8; c0 "Analyzing engine: Rybka v1.2.w32";
    5bk1/5pp1/3N2b1/2B4p/6P1/1R4QP/1P2rP1K/5q2 b - - bm Bxd6; id "wcsac.0527"; acd 19; acs 43; acn 13665720; ce 1144; pm h5h4; pv h5h4 Rb3b8 h4xg3+ Kh2xg3 Qf1g1+ Kg3f3 Re2c2 Nd6b7 Qg1d1+ Kf3g3 Rc2xc5 Rb8xf8+ Kg8xf8 Nb7xc5; c0 "Analyzing engine: Rybka v1.2.w32";
    4r1k1/1pp2bbp/p1n3p1/5p2/5N2/2N2P2/PPP1B1PP/1K1R4 b - - bm Bxc3; id "wcsac.0529"; acd 19; acs 39; acn 17154752; ce 226; pm g6g5; pv g6g5 Be2xa6 b7xa6 Nf4d5 Bg7e5 Kb1c1 Kg8g7 g2g3 Nc6e7 Nd5xe7 Re8xe7 Nc3d5 Re7e8 c2c3; c0 "Analyzing engine: Rybka v1.2.w32";
    r2r4/1q1n1Qpk/p3Pb2/1p1p1N2/1P1p4/8/P5PP/2R1R1K1 w - - bm Re5; id "wcsac.0555"; acd 16; acs 19; acn 7009552; ce 418; pm e6e7; pv e6e7 Nd7e5 Re1xe5 Bf6xe5 e7e8Q Rd8xe8 Qf7xb7 d4d3 Rc1d1 Be5f6 Qb7xd5 d3d2 Qd5xd2 Re8f8; c0 "Analyzing engine: Rybka v1.2.w32";
    2r2rk1/pp1b1ppp/1qn1p3/3pP3/3P2n1/2PB1R2/PP1N2PP/R1BQ3K w - - bm Bxh7+; id "wcsac.0561"; acd 16; acs 59; acn 5580040; ce 79; pm Nd2b3; pv Nd2b3 f7f5 h2h3 Ng4h6 Bc1xh6 g7xh6 Rf3g3+ Kg8h8 Qd1h5 Rf8g8 Rg3xg8+ Rc8xg8 Qh5xh6 Qb6d8; c0 "Analyzing engine: Rybka v1.2.w32";
    1r5r/1bq1bpk1/p1p1pNp1/1p2P1P1/1P1P3N/P2Q4/6P1/3R1RK1 w - - bm Nd5; id "wcsac.0566"; acd 18; acs 11; acn 6693080; ce 732; pm Nf6h5+; pv Nf6h5+ Kg7f8 Nh4xg6+ Kf8e8 Ng6xh8 Ke8d7 Qd3h7 Rb8xh8 Qh7xh8 Qc7d8 Qh8g7 Qd8f8 Qg7xf8 Be7xf8; c0 "Analyzing engine: Rybka v1.2.w32";
    6qk/1p2Q2p/pbb3p1/5pN1/1P1p1P2/3P4/P2B2PP/6K1 w - - bm b5; id "wcsac.0570"; acd 20; acs 55; acn 8008816; ce 443; pm Ng5e6; pv Ng5e6 Bb6d8 Ne6xd8 h7h5 Nd8e6 Bc6d5 Qe7f6+ Kh8h7 Ne6f8+ Kh7h6 Qf6g5+ Kh6g7 Nf8xg6 Qg8e6; c0 "Analyzing engine: Rybka v1.2.w32";
    2n2r1k/1r1qb1pp/2p2p2/ppP3P1/5P1N/1P1N4/KP6/2QR1B2 w - - bm Ne5; id "wcsac.0571"; acd 15; acs 29; acn 6767072; ce 92; pm Bf1g2; pv Bf1g2 Rf8d8 Qc1e3 a5a4 Bg2f3 Qd7e8 g5xf6 a4xb3+ Ka2b1 g7xf6 Qe3e6 Rb7a7 Qe6xb3 Qe8g8; c0 "Analyzing engine: Rybka v1.2.w32";
    2kr2nr/ppp2ppp/1b6/1B2q3/8/4BP2/PPQ3PP/3RR2K w - - bm Bg5; id "wcsac.0576"; acd 21; acs 25; acn 15053016; ce 32744; pm Rd1xd8+; pv Rd1xd8+ Kc8xd8 Qc2d2+ Bb6d4 Be3g5+ Kd8c8 Re1xe5 Ng8f6 Qd2xd4 c7c6 Bb5xc6 Rh8d8 Bc6xb7+ Kc8b8 Qd4xd8+ Kb8xb7 Bg5xf6 g7xf6 Qd8d7+ Kb7b6 Re5b5+ Kb6a6 Qd7b7; c0 "Analyzing engine: Rybka v1.2.w32";
    2rr1b2/8/ppkq1pP1/3pp3/2p5/2BPPpP1/BQ3P2/1RRN1n1K b - - bm Qb8; id "wcsac.0580"; acd 17; acs 49; acn 6009840; ce 147; pm Rc8b8; pv Rc8b8 Kh1g1 Qd6e6 Kg1xf1 Qe6h3+ Kf1e1 Qh3h1+ Ke1d2 Qh1f1 Rc1c2 Qf1xd3+ Kd2c1 Qd3xg6 Bc3b4; c0 "Analyzing engine: Rybka v1.2.w32";
    k1q1bbrr/1p3pp1/p7/5n1n/PP2N2p/1NP5/1BB1Q1PP/2R2R1K b - - bm Bb5; id "wcsac.0582"; acd 14; acs 37; acn 5660520; ce 2; pm Nh5g3+; pv Nh5g3+ Ne4xg3 h4xg3 h2h3 Nf5d6 Nb3a5 b7b6 Na5b3 Be8xa4 Nb3d4 Ba4xc2 Rc1xc2 Qc8b7 Qe2g4; c0 "Analyzing engine: Rybka v1.2.w32";
    1rb2rk1/p1p2ppp/2q5/3R4/2P1N3/bP4B1/P1Q2P1P/1K5R w - - bm Bd6; id "wcsac.0593"; acd 16; acs 10; acn 6693056; ce 158; pm Bg3xc7; pv Bg3xc7 Rb8b6 Bc7xb6 a7xb6 Rh1g1 g7g6 Qc2d3 Ba3e7 Ne4d6 Bc8e6 Nd6f5 Qc6c7 Nf5xe7+ Qc7xe7; c0 "Analyzing engine: Rybka v1.2.w32";
    r6k/1p2RQ1p/3p4/p1q3r1/8/1P4N1/P1b3PP/5R1K w - - bm Nf5; id "wcsac.0602"; acd 39; acs 55; acn 56408920; ce 32752; pm Rf1e1; pv Rf1e1 Qc5c8 Qf7f6+ Kh8g8 Qf6xg5+ Bc2g6 Qg5d5+ Kg8f8 Qd5d4 Qc8c3 Qd4xc3 Bg6f7 Qc3h8+ Bf7g8 Qh8g7; c0 "Analyzing engine: Rybka v1.2.w32";
    r3r1k1/1pp2ppp/p2b4/7q/3P4/1Q4Pb/PP3P1P/RNBR2K1 b - - bm Re3; id "wcsac.0611"; acd 26; acs 39; acn 23255072; ce 32748; pm Qh5e2; pv Qh5e2 Nb1d2 Re8e3 Qb3c2 Bd6xg3 Rd1f1 Bg3xf2+ Rf1xf2 Qe2g4+ Kg1h1 Re3e1+ Nd2f1 Bh3xf1 Qc2xh7+ Kg8xh7 h2h4 Bf1g2+ Kh1h2 Qg4h3; c0 "Analyzing engine: Rybka v1.2.w32";
    1br3k1/1p4p1/p3p2r/5pq1/3Nb3/P1B1PpP1/1P1R3P/2R1Q1K1 b - - bm f2+; id "wcsac.0616"; acd 18; acs 37; acn 10154352; ce 747; pm Rh6xh2; pv Rh6xh2 Rd2xh2 Bb8xg3 Nd4xf3 Be4xf3 Kg1f1 Bg3xe1 Rc1xe1 Qg5g3 Re1e2 Bf3xe2+ Rh2xe2 Kg8f7 Re2g2; c0 "Analyzing engine: Rybka v1.2.w32";
    Rr4k1/1P1n1p2/6p1/3p1N1p/1Pn1p3/6PP/6P1/2R3K1 w - - bm Ne3; id "wcsac.0627"; acd 19; acs 53; acn 21950120; ce 870; pm Ra8xb8+; pv Ra8xb8+ Nd7xb8 Nf5e3 Kg8g7 Ne3xc4 h5h4 Nc4b6 e4e3 Nb6xd5 g6g5 Nd5xe3 g5g4 Rc1c8 Nb8d7; c0 "Analyzing engine: Rybka v1.2.w32";
    3qr1k1/pp3Rp1/2ppP2p/8/4N3/1B4P1/PP5P/4R1K1 w - - bm Rf8+; id "wcsac.0640"; acd 20; acs 55; acn 10691408; ce 847; pm e6e7; pv e6e7 Re8xe7 Rf7xe7+ d6d5 Re7xb7 a7a5 Ne4d6 Qd8xd6 Re1e8+ Qd6f8 Re8xf8+ Kg8xf8 Rb7c7 d5d4; c0 "Analyzing engine: Rybka v1.2.w32";
    5k2/p1q2p1p/2Pr2p1/4Q3/P7/6P1/5P1P/2R3K1 w - - bm Qxd6+; id "wcsac.0641"; acd 21; acs 1; acn 13121592; ce 606; pm Rc1e1; pv Rc1e1 Kf8g8 Qe5e8+ Kg8g7 Re1e7 Qc7xe7 Qe8xe7 Rd6xc6 Qe7xa7 Rc6c4 a4a5 h7h5 Qa7b7 h5h4; c0 "Analyzing engine: Rybka v1.2.w32";
    5k2/6b1/2p4p/P1pr4/2Q5/1P4P1/2P4P/7K w - - bm Qxd5; id "wcsac.0642"; acd 20; acs 33; acn 7717928; ce 796; pm a5a6; pv a5a6 Rd5d1+ Kh1g2 Bg7d4 a6a7 Rd1g1+ Kg2f3 Rg1a1 Qc4a4 Ra1xa4 b3xa4 Kf8e7 a7a8Q Ke7d7; c0 "Analyzing engine: Rybka v1.2.w32";
    5k2/ppq1r1b1/4P3/3Q2R1/P7/8/1P5P/6RK w - - bm Rxg7; id "wcsac.0643"; acd 21; acs 20; acn 10836384; ce 32740; pm Rg1f1+; pv Rg1f1+ Kf8e8 Rg5xg7 Re7xg7 Qd5h5+ Ke8e7 Qh5h4+ Ke7xe6 Qh4f6+ Ke6d7 Qf6xg7+ Kd7c8 Rf1f8+ Qc7d8 Qg7c3+ Kc8d7 Qc3d4+ Kd7e6 Rf8xd8 a7a5 Rd8f8 b7b5 Rf8f6+ Ke6e7 Qd4d6+ Ke7e8 Rf6f8; c0 "Analyzing engine: Rybka v1.2.w32";
    r4r1k/4N2p/4n1p1/4Pp2/1p1P1PP1/1q5P/p5R1/3R1QK1 b - - bm Qxd1; id "wcsac.0655"; acd 16; acs 39; acn 9315104; ce 813; pm Ne6xf4; pv Ne6xf4 Rd1a1 Nf4xg2 g4xf5 Qb3b2 Kg1h1 Ng2e3 Qf1g1 g6xf5 e5e6 Ne3c2 Ne7d5 Nc2xa1 Qg1e3; c0 "Analyzing engine: Rybka v1.2.w32";
    1R2rq1k/2p3p1/Q2p1pPp/8/4P3/8/P1r3PP/1R4K1 w - - bm Rxe8; id "wcsac.0668"; acd 24; acs 0; acn 16435152; ce 793; pm Qa6b5; pv Qa6b5 Rc2c1+ Kg1f2 Rc1c2+ Kf2f1 Re8xb8 Qb5xb8 Kh8g8 Qb8b3+ Kg8h8 Qb3xc2 Qf8e8 Qc2xc7 Qe8xg6; c0 "Analyzing engine: Rybka v1.2.w32";
    5rk1/6pp/3P4/2Q2p2/6n1/2P5/P1q3PP/R4RK1 w - - bm Qc4+; id "wcsac.0673"; acd 18; acs 32; acn 13436464; ce 789; pm d6d7; pv d6d7 Qc2d3 Ra1d1 Qd3e3+ Qc5xe3 Ng4xe3 d7d8Q Rf8xd8 Rd1xd8+ Kg8f7 Rf1e1 f5f4 g2g3 h7h6; c0 "Analyzing engine: Rybka v1.2.w32";
    4rrk1/1pp1R1pp/p7/q1P5/8/5P2/PPQ4P/5R1K w - - bm Qb3+; id "wcsac.0674"; acd 59; acs 3; acn 892096; ce 32758; pm Qc2c4+; pv Qc2c4+ Kg8h8 Qc4f7 Qa5c3 b2xc3 Rf8g8 Re7xe8; c0 "Analyzing engine: Rybka v1.2.w32";
    2k4r/1pp1q1p1/2n1b3/1Q3p1p/2Pr2n1/6P1/3NPPBP/R4RK1 w - - bm Qxb7+; id "wcsac.0711"; acd 18; acs 46; acn 10884008; ce 838; pm Bg2xc6; pv Bg2xc6 b7xc6 Qb5xc6 Kc8d8 Ra1a8+ Be6c8 Ra8xc8+ Kd8xc8 Rf1a1 Qe7b4 Ra1a8+ Qb4b8 Qc6e6+ Rd4d7; c0 "Analyzing engine: Rybka v1.2.w32";
    r6r/1Rp3n1/3k1pq1/3Pp1pp/4P1P1/2B1QP1P/7R/1b4K1 w - - bm Qb6+; id "wcsac.0723"; acd 59; acs 5; acn 1293208; ce 32758; pm Bc3b4+; pv Bc3b4+ Kd6d7 Qe3b6 Kd7e8 Qb6xc7 Qg6f7 Qc7xf7+ Ke8d8 Qf7d7; c0 "Analyzing engine: Rybka v1.2.w32";
    1k1r1b1r/Rpp2ppp/4b3/1q2N3/5Q2/1PN5/2nP1PPP/2BKR3 b - - bm Bxb3; id "wcsac.0747"; acd 16; acs 47; acn 11798176; ce 504; pm Nc2d4; pv Nc2d4 Re1e2 Nd4xe2 Nc3xb5 Ne2xf4 Ra7a8+ Kb8xa8 Nb5xc7+ Ka8b8 Nc7xe6 f7xe6 Ne5f7 Rd8c8 Nf7xh8; c0 "Analyzing engine: Rybka v1.2.w32";
    3r3k/Q5pp/4Nq1n/3B1p2/5P2/4B3/Pr2n1PP/3R1K2 b - - bm Qxe6; id "wcsac.0748"; acd 16; acs 36; acn 7396032; ce 08; pm Rd8e8; pv Rd8e8 Rd1e1 Nh6g4 Re1xe2 Ng4xh2+ Kf1e1 Rb2b1+ Ke1d2 Nh2f1+ Kd2d3 Rb1d1+ Re2d2 Nf1xd2 Be3xd2; c0 "Analyzing engine: Rybka v1.2.w32";
    R7/P3k3/8/8/8/8/7K/r7 w - - bm Rh8; id "wcsac.0757"; acd 59; acs 0; acn 48; ce 32724; pm Kh2g3; pv Kh2g3; c0 "Analyzing engine: Rybka v1.2.w32";
    3r3r/pRn2k1B/2p5/4q3/2p3Q1/4B3/P1P4P/7K w - - bm Qg6+; id "wcsac.0760"; acd 16; acs 36; acn 7392424; ce 1278; pm Rb7xc7+; pv Rb7xc7+ Qe5xc7 Qg4g6+ Kf7e7 Qg6g5+ Ke7f8 Be3c5+ Rd8d6 Qg5f6+ Kf8e8 Bh7g6+ Ke8d7 Bg6f5+ Kd7e8; c0 "Analyzing engine: Rybka v1.2.w32";
    rn3rk1/pbp1qppp/1p2pn2/3p4/1bPP1B2/5NP1/PP2PPBP/RN1Q1RK1 w - - bm c5; id "wcsac.0768"; acd 16; acs 53; acn 7094768; ce 10; pm Nf3e5; pv Nf3e5 Nb8d7 Ne5d3 Bb4d6 Nb1c3 Nf6e4 c4xd5 Ne4xc3 b2xc3 e6xd5 Qd1b3 Bd6xf4 Nd3xf4 Nd7f6; c0 "Analyzing engine: Rybka v1.2.w32";
    r2rbb1Q/3q1k2/6pp/np1p4/8/P3P3/1B3PPP/1BR2RK1 w - - bm Rc7; id "wcsac.0770"; acd 14; acs 18; acn 3794424; ce 467; pm f2f4; pv f2f4 Qd7e7 Rc1c7 Na5c4 Qh8f6+ Kf7g8 Rc7xe7 Nc4xb2 Re7c7 Rd8d6 Qf6xb2 Rd6e6 f4f5; c0 "Analyzing engine: Rybka v1.2.w32";
    r1b1r1k1/pp3pbp/2p3p1/q2n4/3N4/1P2PB2/PBQ2PPP/3R1RK1 w - - bm Nxc6; id "wcsac.0793"; acd 14; acs 3; acn 4469072; ce 19; pm a2a3; pv a2a3 Qa5b6 b3b4 Nd5f6 Nd4b3 Bc8g4 Bf3xg4 Nf6xg4 h2h3 Bg7xb2 Qc2xb2 Ng4e5 Nb3c5 a7a5; c0 "Analyzing engine: Rybka v1.2.w32";
    r1b1k3/1pq2pQ1/p3p1p1/4n3/3NN1pr/8/PPP5/2KR1R2 w q - bm Nb5; id "wcsac.0799"; acd 19; acs 58; acn 14106400; ce 32742; pm Qg7g8+; pv Qg7g8+ Ke8e7 Rf1xf7+ Ne5xf7 Rd1f1 Qc7f4+ Rf1xf4 Rh4h1+ Kc1d2 Rh1h2+ Nd4e2 Rh2h7 Qg8xh7 Ke7d7 Qh7xf7+ Kd7c6 Qf7f8 b7b6 Qf8d6+ Kc6b7 Rf4f7+ Bc8d7 Rf7xd7+ Kb7c8 Qd6c7; c0 "Analyzing engine: Rybka v1.2.w32";
    2r5/1R2pk2/3pN1p1/3Pp1Pp/4P3/rR6/5PKP/2b5 w - - bm Rc7; id "wcsac.0800"; acd 20; acs 50; acn 20910008; ce 116; pm Rb3b6; pv Rb3b6 Ra3c3 Rb6xd6 Bc1a3 Rd6b6 Kf7g8 Rb7b8 Ba3d6 Rb8xc8+ Rc3xc8 Rb6c6 Rc8a8 h2h4 Kg8f7; c0 "Analyzing engine: Rybka v1.2.w32";
    r1b1qrk1/pppnb1pp/4p3/2PpNp2/3PnP2/6P1/PP1NP1BP/R1BQ1RK1 b - - bm Ndxc5; id "wcsac.0814"; acd 17; acs 9; acn 7177864; ce 21; pm Nd7xe5; pv Nd7xe5 f4xe5 b7b6 Nd2xe4 d5xe4 c5xb6 a7xb6 Bc1e3 Bc8b7 Ra1c1 Qe8d7 a2a4 Bb7d5 Qd1c2; c0 "Analyzing engine: Rybka v1.2.w32";
    6k1/1R3p2/p1p5/2P3b1/1P2P1p1/5p1p/5P2/6K1 b - - bm Be3; id "wcsac.0817"; acd 30; acs 50; acn 38572504; ce 32742; pm g4g3; pv g4g3 f2xg3 Bg5e3+ Kg1h2 f3f2 Kh2xh3 f2f1Q+ Kh3g4 Qf1d1+ Kg4h3 Qd1h1+ Kh3g4 Qh1xe4+ Kg4h3 Qe4h1+ Kh3g4 Qh1d1+ Kg4h3 f7f5 Rb7b8+ Kg8g7 Rb8b7+ Kg7g6 Rb7g7+ Kg6xg7 g3g4 Qd1h1+ Kh3g3 f5f4; c0 "Analyzing engine: Rybka v1.2.w32";
    1k1r1b1r/p1p1q3/2p1p3/4Ppp1/4nP2/P2BQ3/1PP3PB/2KR3R b - - bm Rxh2; id "wcsac.0820"; acd 20; acs 42; acn 11351880; ce 91; pm Qe7c5; pv Qe7c5 Qe3xc5 Bf8xc5 Bd3xe4 Bc5e3+ Kc1b1 Rd8xd1+ Rh1xd1 f5xe4 Bh2g1 Be3xg1 Rd1xg1 g5xf4 Kb1c1; c0 "Analyzing engine: Rybka v1.2.w32";
    r7/b1q1kPp1/p2p3p/1p1P4/2NR2P1/PPQ2P2/6K1/8 w - - bm Re4+; id "wcsac.0832"; acd 19; acs 20; acn 13362280; ce 974; pm Rd4f4; pv Rd4f4 Ba7d4 Qc3xd4 Ke7f8 Qd4d3 Qc7e7 Nc4e3 Qe7e5 Qd3h7 Qe5xf4 Ne3f5 Qf4xf5 Qh7g8+ Kf8e7; c0 "Analyzing engine: Rybka v1.2.w32";
    k7/2p1rp1P/KpP2R2/7r/1P6/8/8/8 w - - bm Rh6; id "wcsac.0834"; acd 28; acs 43; acn 9291648; ce 000; pm Rf6xf7; pv Rf6xf7 Re7xf7 b4b5 Rh5f5 h7h8Q+ Rf7f8 Qh8xf8+ Rf5xf8; c0 "Analyzing engine: Rybka v1.2.w32";
    3rk2r/1p1b1pp1/p1n5/2RQP1Bp/1P6/8/1P2qPPP/3R2K1 b - - bm Qxd1+; id "wcsac.0842"; acd 18; acs 6; acn 8411536; ce 222; pm f7f6; pv f7f6 Qd5d2 Qe2xd2 Bg5xd2 Nc6xe5 Bd2c3 Ne5c6 b4b5 a6xb5 Rc5xb5 Bd7c8 Rd1xd8+ Ke8xd8 Bc3d2; c0 "Analyzing engine: Rybka v1.2.w32";
    5rk1/pb3ppp/3qp3/1p1n4/3PB1nQ/6P1/P1r2P1P/R1B2RK1 b - - bm Ndf6; id "wcsac.0845"; acd 15; acs 25; acn 2085768; ce 277; pm f7f5; pv f7f5 Be4xc2 Nd5c3 f2f3 Nc3e2+ Kg1g2 Qd6xd4 Bc1g5 Qd4b2 Ra1d1 Qb2xc2 Rd1d2 Qc2c4 h2h3; c0 "Analyzing engine: Rybka v1.2.w32";
    2rk4/p1rqn1p1/P1n1p2p/3pPp2/BP1P1P2/2R2N2/2R3PP/2Q3K1 w - - bm h4; id "wcsac.0860"; acd 18; acs 59; acn 8825536; ce 275; pm Nf3e1; pv Nf3e1 g7g6 Kg1f1 Rc8b8 Ne1d3 Rb8b6 b4b5 Qd7c8 b5xc6 Kd8e8 Qc1a3 Ke8f7 Nd3c5 Rb6b1; c0 "Analyzing engine: Rybka v1.2.w32";
    8/1p3pkp/p2r1rp1/8/8/2B5/PP5P/5RK1 w - - bm Rxf6; id "wcsac.0863"; acd 22; acs 29; acn 28778112; ce 167; pm h2h4; pv h2h4 h7h6 Kg1g2 g6g5 Bc3e5 Kg7g6 h4h5+ Kg6g7 Kg2g3 Rd6e6 Be5d4 Re6c6 Bd4e5 Rc6d6; c0 "Analyzing engine: Rybka v1.2.w32";
    2b3k1/8/2p5/2Pp2p1/3P1bP1/P1P1p2K/2q1B3/4R2Q b - - bm Ba6; id "wcsac.0869"; acd 19; acs 34; acn 12237512; ce 103; pm Kg8g7; pv Kg8g7 a3a4 Qc2xc3 Kh3g2 Qc3xd4 Qh1f1 Qd4d2 Re1d1 Qd2c2 Rd1c1 Qc2h7 Qf1h1 Qh7e4+ Be2f3; c0 "Analyzing engine: Rybka v1.2.w32";
    r4b1r/ppp3pp/4Q3/4p3/2Pqk3/8/PP1P1PPP/2B1K2R w K - bm Qg4+; id "wcsac.0873"; acd 26; acs 45; acn 28225448; ce 32750; pm Ke1e2; pv Ke1e2 Qd4xf2+ Ke2xf2 Ra8d8 Rh1e1+ Ke4d3 Re1e3+ Kd3c2 Qe6f5+ e5e4 Qf5xe4+ Kc2xc1 Re3e1+ Kc1xb2 Qe4b1+ Kb2a3 Qb1b3; c0 "Analyzing engine: Rybka v1.2.w32";
    rnb3kr/1p1nqppp/p3p3/2ppP3/3P1N2/2NB1Q2/PPP2PP1/R3K2R w KQ - bm Bxh7+; id "wcsac.0875"; acd 15; acs 53; acn 7847656; ce 14; pm 00+; pv OOO h7h6 d4xc5 Nd7xc5 Rh1h5 Nb8c6 Qf3g3 Qe7c7 Kc1b1 Bc8d7 a2a3 Nc5xd3 Nf4xd3 Nc6a5; c0 "Analyzing engine: Rybka v1.2.w32";
    3q4/p2nbk1p/2R1p1pB/1p1rPp2/8/5N1P/PPQ2PP1/7K w - - bm Rxe6; id "wcsac.0876"; acd 17; acs 34; acn 7635640; ce 61; pm Rc6c8; pv Rc6c8 Qd8b6 Rc8h8 Qb6c5 Rh8xh7+ Kf7e8 Rh7h8+ Ke8f7 Qc2xc5 Nd7xc5 Bh6g5 Rd5d7 Rh8h7+ Kf7f8; c0 "Analyzing engine: Rybka v1.2.w32";
    2r4r/1pq1kpp1/p3pn1p/8/2P2bPP/2B5/PPB1Q3/1K1R1R2 w - - bm Rxf4; id "wcsac.0880"; acd 17; acs 15; acn 9354576; ce 551; pm Bc3b4+; pv Bc3b4+ Bf4d6 Bb4xd6+ Qc7xd6 Rd1xd6 Ke7xd6 g4g5 h6xg5 h4xg5 Nf6e8 Rf1xf7 Rh8h1+ Bc2d1 Rc8xc4; c0 "Analyzing engine: Rybka v1.2.w32";
    rq2kb1r/1b1n1ppp/p1n5/1p1Np3/4P3/1B1RBN2/PP2QPPP/R5K1 w kq - bm Ng5; id "wcsac.0892"; acd 15; acs 12; acn 3734936; ce 175; pm Ra1c1; pv Ra1c1 Bf8d6 Nf3g5 Nc6d4 Be3xd4 e5xd4 Qe2h5 g7g6 Qh5h6 Bb7xd5 Bb3xd5 Bd6f4 Qh6g7 Bf4xc1; c0 "Analyzing engine: Rybka v1.2.w32";
    1r4k1/p4ppp/8/1B6/3rP2K/8/PPP3q1/R1BQ1R2 b - - bm Rxb5; id "wcsac.0901"; acd 59; acs 7; acn 1809440; ce 32758; pm Rd4xe4+; pv Rd4xe4+ Rf1f4 g7g5+ Kh4h5 Qg2h3+ Kh5xg5 Rb8xb5+ Qd1d5 Rb5xd5+ Kg5f6 Re4e6; c0 "Analyzing engine: Rybka v1.2.w32";
    2rnr1k1/ppq2p1p/5Qp1/2N5/4b3/2P1B1b1/PP2B1P1/3R1R1K w - - bm Bh6; id "wcsac.0915"; acd 14; acs 33; acn 1885336; ce 164; pm Be2g4; pv Be2g4 Rc8a8 Be3h6 Be4xg2+ Kh1xg2 Bg3e5 Nc5d7 Qc7c6+ Qf6xc6 Nd8xc6 Bh6f4 Kg8g7 Nd7xe5 Nc6xe5; c0 "Analyzing engine: Rybka v1.2.w32";
    7k/1p1bbn2/1q2p2p/p2pP1p1/1PpP1rNP/P1P3Q1/1B2B3/6RK w - - bm Nxh6; id "wcsac.0919"; acd 16; acs 26; acn 8276960; ce 83; pm Qg3h2; pv Qg3h2 a5xb4 a3xb4 Rf4xg4 Be2xg4 g5xh4 Qh2c2 Qb6d8 Qc2g6 Qd8f8 Bg4xe6 Bd7xe6 Qg6xe6 Nf7g5; c0 "Analyzing engine: Rybka v1.2.w32";
    r1bqnrk1/ppp2p2/2np1bpp/3NN3/3PQ3/3B4/PPP2PPP/R1B1R1K1 w - - bm Nxf7; id "wcsac.0924"; acd 27; acs 52; acn 19997248; ce 32752; pm Ne5xg6; pv Ne5xg6 Kg8g7 Ng6xf8 Kg7xf8 Bc1xh6+ Bf6g7 Qe4h7 f7f5 Re1xe8+ Kf8xe8 Qh7g8+ Bg7f8 Qg8xf8+ Ke8d7 Bd3xf5; c0 "Analyzing engine: Rybka v1.2.w32";
    2rq1rk1/pp3ppp/3p4/6P1/b3pP2/1N4Q1/PPP3P1/2KR3R w - - bm Rxh7; id "wcsac.0928"; acd 17; acs 3; acn 5412768; ce 87; pm Qg3h3; pv Qg3h3 h7h6 g5xh6 g7g6 Qh3e3 Ba4xb3 a2xb3 d6d5 c2c4 Qd8a5 Qe3d4 f7f6 Qd4xd5+ Qa5xd5; c0 "Analyzing engine: Rybka v1.2.w32";
    3rr1k1/pb3p1p/qp2p1pB/2p4n/3pN3/2P2B1Q/PP5P/R2R3K w - - bm Qxh5; id "wcsac.0934"; acd 15; acs 40; acn 6817344; ce 000; pm Qh3g2; pv Qh3g2 Bb7xe4 Bf3xe4 e6e5 Bh6g5 Nh5f4 Qg2g3 Qa6e2 Be4c6 Re8f8 Bg5xd8 Rf8xd8 Qg3e1 Qe2h5; c0 "Analyzing engine: Rybka v1.2.w32";
    1k5r/1r1B2pp/1PQ5/4pp2/R7/3q3P/5PP1/6K1 w - - bm Bc8; id "wcsac.0940"; acd 20; acs 36; acn 14918128; ce 1093; pm Bd7xf5; pv Bd7xf5 Qd3d1+ Kg1h2 Qd1xa4 Qc6xa4 Rb7xb6 Bf5e4 Rb6f6 Qa4a8+ Kb8c7 Qa8xh8 Kc7d6 Qh8xg7 Rf6f4; c0 "Analyzing engine: Rybka v1.2.w32";
    r4rb1/pp2q1bk/1np2npp/2N1Np2/3P1P2/4P1PB/PPQB3P/R4RK1 w - - bm Bxf5; id "wcsac.0943"; acd 14; acs 36; acn 1916096; ce 242; pm Ne5xg6; pv Ne5xg6 Qe7c7 Bh3xf5 Rf8e8 e3e4 Bg8f7 e4e5 Nf6d5 Bf5e4 Kh7g8 f4f5 Nb6d7; c0 "Analyzing engine: Rybka v1.2.w32";
    2kr2nr/ppp1q1pp/2npbp2/3B4/4P3/B1Q2N2/P4PPP/1R2R1K1 w - - bm Rxb7; id "wcsac.0961"; acd 15; acs 47; acn 7202384; ce 356; pm Bd5xc6; pv Bd5xc6 b7xc6 Qc3xc6 Qe7e8 Qc6a6+ Kc8d7 Ba3xd6 Qe8f7 Rb1b7 Kd7e8 Rb7xc7 Qf7h5 e4e5 f6f5; c0 "Analyzing engine: Rybka v1.2.w32";
    4rr2/p1q2p1k/1p1RbQp1/4Pp1p/2P4R/5N1P/PP4P1/7K w - - bm Rxh5+; id "wcsac.0970"; acd 18; acs 10; acn 9075512; ce 155; pm Nf3g5+; pv Nf3g5+ Kh7g8 Ng5xe6 f7xe6 Qf6xg6+ Qc7g7 Qg6xh5 Rf8f7 Qh5e2 Qg7g5 Rd6d4 Rf7g7 Rh4h5 Qg5e7; c0 "Analyzing engine: Rybka v1.2.w32";
    rnb2k2/ppqpRr2/2p3p1/8/3Q4/8/P4PPP/R5K1 w - - bm Qh8+; id "wcsac.0973"; acd 59; acs 4; acn 1269672; ce 32758; pm Ra1e1; pv Ra1e1 Kf8g8 Re7e8+ Rf7f8 Re8xf8+ Kg8xf8 Qd4f6+ Kf8g8 Qf6xg6+ Kg8f8 Re1e8; c0 "Analyzing engine: Rybka v1.2.w32";
    r1bq1rk1/ppppnpp1/1b5p/1Bn1P1B1/2Q5/2P2N2/PP3PPP/RN3RK1 w - - bm Qh4; id "wcsac.0974"; acd 17; acs 40; acn 7961144; ce 17; pm b2b4; pv b2b4 Nc5e6 Bg5h4 a7a5 Qc4e4 d7d5 e5xd6 ep c7xd6 Bh4xe7 Qd8xe7 Bb5d3 f7f5 Qe4d5 Rf8f7; c0 "Analyzing engine: Rybka v1.2.w32";
    rr4k1/4pp1p/p2p1bp1/q2P3P/1p4P1/P4P2/1PPQ4/2KR1B1R b - - bm Bxb2+; id "wcsac.0987"; acd 15; acs 35; acn 2737024; ce 208; pm Qa5a4; pv Qa5a4 Qd2d3 b4xa3 b2xa3 Bf6g5+ Rd1d2 Rb8b5 Kc1d1 Bg5xd2 h5xg6 h7xg6 Kd1xd2 Ra8c8 Qd3e4; c0 "Analyzing engine: Rybka v1.2.w32";
    2k5/1pp2ppp/4p3/1P5q/5n2/P1N2r1P/1PQ3PK/3R4 b - - bm Nxh3; id "wcsac.0998"; acd 21; acs 54; acn 17412752; ce 290; pm Nf4xg2; pv Nf4xg2 Qc2xg2 Qh5e5+ Kh2h1 Qe5e3 Kh1h2 Rf3f2 Rd1g1 Qe3e5+ Kh2h1 Rf2xg2 Rg1xg2 c7c6 b5xc6; c0 "Analyzing engine: Rybka v1.2.w32";
User avatar
sje
Posts: 4675
Joined: Mon Mar 13, 2006 7:43 pm

Re: About 10% of the WCSAC EPD positions are broken.

Post by sje »

First, it would be nice if the analyzing program were to emit SAN moves in the EPD analysis. It is a requirement, after all.

There is a problem that there is no real consensus as to what constitutes a well formed chess problem (and answer) outside of the obvious cases of certain checkmating.

It would be nice if some of the heavy machinery like Hydra were available for doing a common good by running a methodological scan of various test suites. Eight or more hours a day for a year would give answers for WCSAC that would be definitive for nearly all purposes.
jdart
Posts: 4366
Joined: Fri Mar 10, 2006 5:23 am
Location: http://www.arasanchess.org

Re: About 10% of the WCSAC EPD positions are broken.

Post by jdart »

I think more than 10% are broken, over 50% I would guess. I stopped using this test suite a while ago.

As you say there are alternate mate sequences in many cases. But there are also positions where there is no clear best move, or the supplied solution is not best.

--Jon
Dann Corbit
Posts: 12540
Joined: Wed Mar 08, 2006 8:57 pm
Location: Redmond, WA USA

Re: About 10% of the WCSAC EPD positions are broken.

Post by Dann Corbit »

jdart wrote:I think more than 10% are broken, over 50% I would guess. I stopped using this test suite a while ago.

As you say there are alternate mate sequences in many cases. But there are also positions where there is no clear best move, or the supplied solution is not best.

--Jon
I don't think it is nearly so bad as 50%. Of the 900 or so not listed here, Rybka solved them all and held the solution for at least 6 plies and at a depth of at least 16 plies.

Of those listed here, I guess that about 100 will remain as bugs and 20 are actually just solutions that were not discovered in time for one reason or another.

I guess that the 10% error rate is about the same as any other test suite before it gets a thorough debugging.
jdart
Posts: 4366
Joined: Fri Mar 10, 2006 5:23 am
Location: http://www.arasanchess.org

Re: About 10% of the WCSAC EPD positions are broken.

Post by jdart »

The fact that Rybka gave the "correct" solution does not mean there are not other alternate solutions. This test suite in particular has a lot of positions where there's something like a mate in 4 and an alternative mate in 5. Many programs will find the mate in 5 first (because of move ordering) and stop there. IMO it is not reasonable to score this as incorrect.
Dann Corbit
Posts: 12540
Joined: Wed Mar 08, 2006 8:57 pm
Location: Redmond, WA USA

Re: About 10% of the WCSAC EPD positions are broken.

Post by Dann Corbit »

jdart wrote:The fact that Rybka gave the "correct" solution does not mean there are not other alternate solutions. This test suite in particular has a lot of positions where there's something like a mate in 4 and an alternative mate in 5. Many programs will find the mate in 5 first (because of move ordering) and stop there. IMO it is not reasonable to score this as incorrect.
I agree. In fact, a proven mate in 50 is just as good as a proven mate in 1. Both moves clearly win the game.

Similarly, if a move is a few centipawns better than some other choice, it is very much up in the air which of the two is better.

I am interested in debugging test suites because I think that better test suites can make for better tactical understanding. And bad test suites may even cause people to "detune" their engines to as to get the wrong answers instead of the right ones.