Author: Drexel,Michael
Date: 12:17:59 10/19/05
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No, this position was created by me yesterday evening to make it clear there exists a Bug in Fritz 9. I could create hundreds of them, the specific position doesn´t matter at all. While analysing an endgame position I got very strange scores. Fritz evaluated a position -2 which should have been evaluated at least -6. So I knew that it will likely drop pieces under certain circumstances and I created this position. There exists probably an almost infinte number of endgame positions where this bug occurs. The engine is therefore IMO useless for endgame analysis. Another extreme example: [D]nkr1n3/p1p5/2p5/8/8/8/1K6/RB6 w - - 0 1 Analysis by Fritz 9: 1.Le4 c5 2.Lc6 Sd6 3.Tc1 Sc4+ 4.Kc3 Sab6 ³ (-0.36) Depth: 7/15 00:00:00 23kN 1.Ld3! ³ (-0.36) Depth: 7/15 00:00:00 38kN 1.Ld3 Sb6 2.Tc1 Td8 3.Le4 c5 4.Lf3 Td2+ 5.Kc3 ³ (-0.37) Depth: 8/19 00:00:00 97kN 1.Le4! ³ (-0.36) Depth: 8/19 00:00:00 103kN 1.Le4 c5 2.Lc6 Sd6 3.Kc1 Sb6 4.Ta5 c4 5.Ta3 ³ (-0.38) Depth: 9/19 00:00:00 221kN 1.Le4 c5 2.Lc6 Sd6 3.Kc2 Sb6 4.Ta5 Sd5 5.Kc1 c4 ³ (-0.39) Depth: 10/24 00:00:02 774kN 1.Le4 c5 2.Lc6 Sd6 3.Kb1 Sb6 4.Ta5 c4 5.Th5 Te8 6.Th7 ³ (-0.39) Depth: 11/26 00:00:03 1970kN 1.Le4 c5 2.Lc6 Sd6 3.Kb1 Te8 4.Ta5 Sc4 5.Ta6 Sab6 6.Kc2 Se3+ 7.Kb3 ³ (-0.41) Depth: 12/30 00:00:07 6547kN 1.Ld3! ³ (-0.40) Depth: 12/30 00:00:08 8098kN 1.Ld3 Sb6 2.Tc1 Td8 3.La6 Td2+ 4.Ka1 c5 5.Th1 Td1+ 6.Txd1 Sd6 ³ (-0.55) Depth: 13/31 00:00:41 50615kN 1.Le4! ³ (-0.55) Depth: 13/31 00:00:42 53001kN 1.Le4 c5 2.Tc1 Sd6 3.Ld3 Sc4+ 4.Ka2 Td8 5.Le4 Td2+ 6.Kb3 Tb2+ 7.Kc3 Tb3+ 8.Kc2 Sab6 9.Th1 Se3+ ³ (-0.42) Depth: 13/31 00:00:46 57578kN nkr1n3/p1p5/2p5/8/8/8/1K6/RB6 w - - 0 1 Analysis by Shredder 9: 1.Le4 -+ (-5.81) Depth: 1/1 00:00:00 1.Le4 -+ (-5.81) Depth: 1/1 00:00:00 1.Le4 c5 -+ (-5.97) Depth: 2/4 00:00:00 1.Le4 Sd6 2.Lf3 -+ (-6.04) Depth: 3/5 00:00:00 1.Kb3 -+ (-6.02) Depth: 3/5 00:00:00 1.Kb3 Td8 2.Le4 -+ (-5.97) Depth: 3/5 00:00:00 1.Kb3 Sb6 2.Lf5 Td8 -+ (-6.20) Depth: 4/6 00:00:00 1.Kb3 Sb6 2.Lf5 Td8 3.Kb4 -+ (-6.21) Depth: 5/9 00:00:00 1.Kb3 Sb6 2.Le4 Sd5 3.Ta6 Td8 -+ (-6.41) Depth: 6/9 00:00:00 1.Le4 -+ (-6.40) Depth: 6/9 00:00:00 1.Le4 Sd6 2.Lxc6 Sb6 3.Kb3 Sbc4 -+ (-6.34) Depth: 6/9 00:00:00 1.Le4 Sd6 2.Lxc6 Sb6 3.Kb3 Sbc4 4.Kb4 -+ (-6.37) Depth: 7/12 00:00:00 17kN 1.Le4 c5 2.Ta5 Sb6 3.Kb3 c4+ 4.Kb4 c5+ -+ (-6.47) Depth: 8/15 00:00:00 57kN 1.Le4 c5 2.Lc6 Td8 3.Tc1 Sb6 4.Txc5 Sf6 5.Kb3 -+ (-6.44) Depth: 9/15 00:00:00 120kN 1.Le4 c5 2.Lc6 Sd6 3.Kb3 Tf8 4.Ta5 c4+ 5.Kb4 Sb6 -+ (-6.54) Depth: 10/19 00:00:00 202kN 1.Le4 c5 2.Lc6 Sd6 3.Th1 Tf8 4.Th7 Sb6 -+ (-6.57) Depth: 11/23 00:00:01 387kN 1.Le4 c5 2.Lc6 Sd6 3.Tc1 c4 -+ (-6.70) Depth: 12/25 00:00:01 793kN 1.Le4 c5 2.Lc6 Sd6 3.Tg1 Sb6 4.Tg5 c4 5.Kc3 Th8 6.Kb4 Th3 7.Tc5 -+ (-6.69) Depth: 13/24 00:00:02 1641kN 1.Le4 c5 2.Lc6 Sd6 3.Th1 Sb6 4.Th5 c4 5.Kc3 Tg8 6.Kb4 a5+ 7.Txa5 Tg3 -+ (-6.78) Depth: 14/29 00:00:04 2649kN 1.Le4 c5 2.Lc6 Sd6 3.Tc1 c4 4.Th1 Tg8 5.Lxa8 -+ (-6.92) Depth: 15/34 00:00:09 5911kN 1.Ld3 -+ (-6.91) Depth: 15/35 00:00:16 11296kN 1.Ld3 Sd6 -+ (-6.91) Depth: 15/35 00:00:18 12539kN 1.Ld3 Sd6 2.La6 Tg8 3.Tc1 Sb6 4.Txc6 Tg2+ 5.Kb3 Tg3+ 6.Kb2 Sa4+ 7.Kc2 Se4 8.Te6 Tg2+ 9.Kc1 Sd6 10.Te7 Sc3 -+ (-7.06) Depth: 16/35 00:00:26 18062kN 1.Le4 -+ (-7.05) Depth: 16/35 00:00:26 18148kN 1.Le4 c5 2.Lc6 Sd6 3.Tg1 Th8 4.Tg6 Sb6 -+ (-6.95) Depth: 16/35 00:00:30 20300kN 1.Le4 c5 2.Tg1 Sd6 3.Lc2 Sb6 4.Tg5 c4 5.Kc3 -+ (-7.03) Depth: 17/37 00:00:42 28932kN Or with pawns for both sides: [D]nkr1n3/p1p4P/2p5/8/8/8/1K6/RB6 b - - 0 1 Analysis by Fritz 9: 1...Sd6 2.h8D Txh8 3.Ld3 Th3 4.Lc2 Sb6 ³ (-0.39) Depth: 7/18 00:00:00 14kN 1...Sd6 2.h8D Txh8 3.Lg6 Sb6 4.Ld3 c5 5.Kc2 ³ (-0.39) Depth: 8/20 00:00:00 57kN 1...Sd6 2.h8D Txh8 3.Ta6 Th2+ 4.Ka1 Sb6 5.Ld3 c5 6.Kb1 ³ (-0.41) Depth: 9/22 00:00:00 201kN 1...Sd6! ³ (-0.70) Depth: 10/26 00:00:00 713kN 1...Sd6! µ (-0.98) Depth: 10/26 00:00:00 743kN 1...Sd6! -+ (-1.54) Depth: 10/26 00:00:00 870kN 1...Sd6-- µ (-1.26) Depth: 11/26 00:00:01 1407kN 1...Sd6 2.Ld3 Th8 3.La6 Txh7 4.Tg1 Th8 5.Kb3 Sb6 6.Tg7 Th3+ 7.Kc2 Th2+ ³ (-0.37) Depth: 11/28 00:00:02 2737kN 1...Sf6! ³ (-0.38) Depth: 11/28 00:00:02 3080kN 1...Sf6 2.h8D Txh8 3.Lg6 Sb6 4.Kb3 Th3+ 5.Kc2 Sfd5 6.Le4 Se3+ 7.Kb2 Th1 ³ (-0.41) Depth: 11/30 00:00:03 3997kN 1...Sf6 2.h8D Txh8 3.Lf5 Th2+ 4.Kb3 Sb6 5.Te1 a5 6.Te6 a4+ 7.Ka3 Ta2+ 8.Kb4 Sbd5+ 9.Kc5 ³ (-0.44) Depth: 12/29 00:00:05 6550kN 1...Sf6 2.Ld3 Sb6 3.Tf1 Sbd5 4.h8D ³ (-0.47) Depth: 13/32 00:00:11 14765kN 1...Sf6 2.Ld3 Sb6 3.Tf1 Sbd5 4.h8D Txh8 5.Lg6 a5 6.Ta1 Th2+ 7.Kb3 Tb2+ 8.Kxb2 Sf4 ³ (-0.47) Depth: 14/32 00:00:17 23366kN Even if such wrong evaluations would be easy to spot for any human (except one ;)), you hardly can trust such an engine. The positions might occur only in the search. Michael
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