Author: Dann Corbit
Date: 11:32:30 07/22/03
Go up one level in this thread
On July 22, 2003 at 02:18:04, Dann Corbit wrote:
>On July 21, 2003 at 23:53:48, Normand M. Blais wrote:
>
>>The following position occured in a game between two chess programs (My program
>>had white).
>>
>>[d]r3r1k1/1p3ppp/2n1qn2/p1b1pNB1/3pP3/P2B4/1PP2PPP/R2Q1RK1 w - -
>>
>>After the game, I decided to let the program analyse the position again just for
>>fun. But then I notice that, after finding the correct move, the pv line at
>>depth 6 was ending in a checkmate while the score at that depth was 0.02. I
>>suspect that this is a bug. Any idea how this could happend?
>>
>>NMB
>>
>>Here is the analysis:
>>
>> 1 -0.09 0 58 a4
>> 2 -0.19 0 1404 a4 Rac8
>> 3 0.05 0 2401 Qf3 Nd7 Rfd1
>> 4 -0.05 2 12896 Qf3 Nd7 Rfd1 Rac8
>> 5 -0.04 7 50855 Qf3 Nd7 Rfd1 Rac8 a4
>> 6 0.02 23 147187 Bc4 Qxc4 Bxf6 Bf8 Qg4 Qxc2 Nxg7 Bxg7 Qxg7#
>> 7 0.15 81 515963 Bc4 Qxc4 Bxf6 Bf8 Qg4 h5 Nh6+ Kh8
>> 8 0.02 296 1695515 Bc4 Qxc4 Bxf6 Bf8 Nxg7 Bxg7 Qg4 Qxc2 Qxg7#
>
>There seems to be some difference of opinion as to what the best thing to do
>here is:
>
>Crafty:
> clearing hash tables
> time surplus 0.00 time limit 16:39 (16:39)
> depth time score variation (1)
> 6-> 0.44 0.67 1. Qf3 Nd7 2. b3 Qg6 3. h4 f6
> 7 0.71 0.64 1. Qf3 Nd7 2. Qg3 Qg6 3. Nh4 Qh5 4.
> Nf5
> 7-> 1.64 0.64 1. Qf3 Nd7 2. Qg3 Qg6 3. Nh4 Qh5 4.
> Nf5
> 8 3.24 0.53 1. Qf3 Nd7 2. b3 Qg6 3. Bd2 Qf6 4.
> Bc4 a4 5. bxa4 Rxa4
> 8-> 6.52 0.53 1. Qf3 Nd7 2. b3 Qg6 3. Bd2 Qf6 4.
> Bc4 a4 5. bxa4 Rxa4
> 9 8.93 0.53 1. Qf3 Nd7 2. b3 Qg6 3. Bd2 Qf6 4.
> Bc4 a4 5. bxa4 Rxa4
> 9 23.07 0.58 1. f4 exf4 2. Rxf4 Nd7 3. Qf1 f6 4.
> Bh4 Nde5 5. Be2
> 9 24.39 0.90 1. Bc4 Qxc4 2. Bxf6 g6 3. Nh6+ Kf8
> 4. b3 Qc3 5. h3 a4
> 9-> 24.73 0.90 1. Bc4 Qxc4 2. Bxf6 g6 3. Nh6+ Kf8
> 4. b3 Qc3 5. h3 a4
> 10 26.01 0.53 1. Bc4 Qxc4 2. Bxf6 g6 3. Nh6+ Kf8
> 4. Rc1 Be7 5. Ng4 Qc5 6. Qf3 Bxf6 7.
> Nxf6
> 10 50.74 0.57 1. f4 Nd7 2. Qg4 Kh8 3. Qg3 g6 4. Nh4
> f6 5. Bh6 Rac8 6. fxe5 Ndxe5
> 10-> 1:10 0.57 1. f4 Nd7 2. Qg4 Kh8 3. Qg3 g6 4. Nh4
> f6 5. Bh6 Rac8 6. fxe5 Ndxe5
> 11 2:00 0.52 1. f4 exf4 2. Rxf4 Nd7 3. Qg4 Nde5
> 4. Qg3 Nxd3 5. cxd3 Rac8 6. Nh6+ gxh6
> 7. Be7+ Qg6 8. Bxc5 Qxg3 9. hxg3
> 11 2:43 0.56 1. Qf3 Nd7 2. b3 h6 3. Bc4 Qg6 4. Bd2
> Ne7 5. Nxe7+ <HT>
> 11 3:06 0.59 1. Bc4 Qxc4 2. Bxf6 g6 3. Nh6+ Kf8
> 4. Ng4 Kg8 5. Qf3 Be7 6. Nxe5 Qxc2
> 11-> 3:19 0.59 1. Bc4 Qxc4 2. Bxf6 g6 3. Nh6+ Kf8
> 4. Ng4 Kg8 5. Qf3 Be7 6. Nxe5 Qxc2
> 12 3:28 0.58 1. Bc4 Qxc4 2. Bxf6 g6 3. Nh6+ Kf8
> 4. Qf3 Be7 5. Bxe7+ Kxe7 6. b3 Qe6
> 7. Rad1 Kf8 8. h3
> 12-> 5:16 0.58 1. Bc4 Qxc4 2. Bxf6 g6 3. Nh6+ Kf8
> 4. Qf3 Be7 5. Bxe7+ Kxe7 6. b3 Qe6
> 7. Rad1 Kf8 8. h3
> 13 5:46 0.52 1. Bc4 Qxc4 2. Bxf6 g6 3. Nh6+ Kf8
> 4. Qf3 Be7 5. Bxe7+ Kxe7 6. Rad1 a4
> 7. b3 axb3 8. cxb3 Qe6 9. b4
> time=16:39 cpu=98% mat=0 n=320857243 fh=92% nps=321k
> ext-> chk=6264616 cap=1032852 pp=132168 1rep=380104 mate=26868
> predicted=0 nodes=320857243 evals=88678232
> endgame tablebase-> probes done=0 successful=0
>
>Ruffian:
> r3r1k1/1p3ppp/2n1qn2/p1b1pNB1/3pP3/P2B4/1PP2PPP/R2Q1RK1 w - -
> Depth Time Score Best line
> 8/18 1.41 0.18 Qe2 Ne7 Bc4 Qb6 Qf3 Nxf5 Qxf5 Qc6 Rfe1
> 8--> 1.78 0.18 Qe2 Ne7 Bc4 Qb6 Qf3 Nxf5 Qxf5 Qc6 Rfe1
> 9/23 3.41 0.14 Qe2 Ne7 Bc4 Qb6 Ng3 Rac8 Rab1 Qc7 Bxf6 gxf6
> 9/23 6.37 x.xx Qf3
> 9/23 8.78 0.19 Qf3 Rac8 Nh6+ Kf8 Bxf6 Qxf6 Qxf6 gxf6 Bc4 Rc7 Nf5
> 9--> 9.29 0.19 Qf3 Rac8 Nh6+ Kf8 Bxf6 Qxf6 Qxf6 gxf6 Bc4 Rc7 Nf5
> 10/23 14.63 0.19 Qf3 Rac8 Nh6+ Kf8 Bxf6 Qxf6 Qxf6 gxf6 f4 Kg7 Nf5+
> Kh8 Bc4
> 10--> 19.43 0.19 Qf3 Rac8 Nh6+ Kf8 Bxf6 Qxf6 Qxf6 gxf6 f4 Kg7 Nf5+
> Kh8 Bc4
> 11/27 1:08 0.23 Qf3 Kh8 Qe2 Nd7 Rfd1 Ne7 Nxe7 Bxe7 Bc4 Qd6 Be3 Qc7
> 11--> 1:20 0.23 Qf3 Kh8 Qe2 Nd7 Rfd1 Ne7 Nxe7 Bxe7 Bc4 Qd6 Be3 Qc7
> 12/31 3:40 0.26 Qf3 Rac8 c3 dxc3 bxc3 Kh8 Rfb1 Rc7 Bc2 Nd7 Rd1 Rec8
> Qe2
> 12--> 4:08 0.26 Qf3 Rac8 c3 dxc3 bxc3 Kh8 Rfb1 Rc7 Bc2 Nd7 Rd1 Rec8
> Qe2
> 13/33 11:04 0.27 Qf3 Nd7 Rfd1 Ne7 Bb5 Nc6 c3 a4 Rac1 Qg6 cxd4 exd4
> Bf4 Nde5
> 13--> 12:02 0.27 Qf3 Nd7 Rfd1 Ne7 Bb5 Nc6 c3 a4 Rac1 Qg6 cxd4 exd4
> Bf4 Nde5
> 14... 12:02 1/43 Qf3
>
>Time: 16:39, cpu 95.57%, nodes 458063864, nps 458504
>Hash: 128M, used 99%, hits 23%
>EGTB: probs 0, hits 0
>
>Chess Tiger 14 likes Rc1:
>r3r1k1/1p3ppp/2n1qn2/p1b1pNB1/3pP3/P2B4/1PP2PPP/R2Q1RK1 w - - ce 56; acd 14; acs
>4; pv Rc1 Ne7 Qe2 Nxf5 exf5 Qb6 Bb5 Rec8 c3 dxc3 Rxc3 Nd5 Rf3 f6 Bc4;|Ra1c1
>
>ChessMaster:
>Time Depth Score Positions Moves
>8:55 3/12 0.68 58866439 1.Qf3 Nd7 2.Bb5 Rec8 3.Rfd1 a4
> 4.Rac1 g6 5.Ng3 Be7 6.Bd2 Bh4
>
>The Chessmaster recommends: Queen to f3.
>
>Analysis: You move your queen to f3. Black replies by moving the knight to d7.
>You move your bishop to b5. Black responds with rook at e8 to c8. You move your
>rook at f1 to d1. Black responds with the pawn to a4. You move your rook at a1
>to c1. Black counters by moving the pawn to g6, which attacks your knight. You
>move your knight to g3, which moves it to safety. Black counters by moving the
>bishop to e7, which threatens your bishop at g5. You move your bishop to d2,
>which moves it to safety. Black responds by moving bishop to h4.
>
>As a result of this sequence of moves, Black's mobility is slightly decreased.
>Additionally, Black's pawn structure slightly weaker.
>
>
>Phalanx:
>r3r1k1/1p3ppp/2n1qn2/p1b1pNB1/3pP3/P2B4/1PP2PPP/R2Q1RK1 w - -
> -> increment adds 1440 s to soft time limit
> -> soft time limit 3154.28 s
> -> hard time limit 41599.9 s
> 6 35 63 58602 Qd1-e2 Nf6-d7 Pf2-f3 Pa5-a4
> 6 -> 0:01.16 124167 0 turns
> 7 55 231 289628 Qd1-e2 Nf6-d7 Qe2-g4
> 7 -> 0:03.21 452253 0 turns
> 8 36 471 728667 Qd1-e2 Nf6-d7 Qe2-g4 Qe6-g6 Nf5-h4 Qg6-e6
> Qg4xe6 Re8xe6 Bd3-c4 Re6-d6
> 8 40 1225 2022612 Pf2-f4 Nf6-d7 Qd1-g4 Qe6-g6 Qg4-f3
> 8 45 1370 2317380 Bd3-c4 !
> 8 70 1420 2443319 Bd3-c4 Qe6xc4 Bg5xf6 Pg7-g6 Nf5-h6 Kg8-f8
> Qd1-d2 Bc5-e7 Pb2-b3 Qc4-e6
> 8 -> 0:14.45 2474828 2 turns
> 9 75 1688 2921312 Bd3-c4 Qe6xc4 Bg5xf6 Pg7-g6 Qd1-d2 Pa5-a4
> 9 -> 0:24.03 4177378 0 turns
> 10 59 3091 5453579 Bd3-c4 Qe6xc4 Bg5xf6 Pg7-g6 Qd1-d2 Pa5-a4
> Nf5-h6 Kg8-f8 Ra1-d1 Re8-e6 Nh6-g4 Ra8-c8
> 10 -> 0:52.36 9412593 0 turns
> 11 62 8140 13821490 Bd3-c4 Qe6xc4 Bg5xf6 Pg7-g6 Qd1-d2 Pa5-a4
> Nf5-h6 Kg8-f8 Qd2-g5 Ra8-a6 Ra1-c1 Ra6-b6
> Pb2-b4
> 11 -> 4:43.81 45012677 0 turns
> 12 64 36867 58734717 Bd3-c4 Qe6xc4 Bg5xf6 Pg7-g6 Qd1-d2 Pa5-a4
> Nf5-h6 Kg8-f8 Rf1-e1 Re8-e6 Nh6-g4 Kf8-g8
> Qd2-h6 Bc5-f8
> 12 -> 10:19.54 98381024 0 turns
> 13 70 89488 141218659 Bd3-c4 Qe6xc4 Bg5xf6 Pg7-g6 Qd1-d2 Re8-e6
> Nf5-h6 Kg8-f8 Nh6-g4 Kf8-g8 Pb2-b3 Qc4-c3
> Qd2xc3 Pd4xc3 Rf1-d1 Pa5-a4 Ng4-h6 Kg8-f8
> 13 -> 28:51.54 271014655 0 turns
Yace:
usetime = 86399.00, mintime = 86399.00 maxtime = 86399.00 tl 86399.00 ml 0 tu 0.
00
11 0.001 -0.21 1t 1.Bxf6 Qxf6 {0}
34 0.017 -0.02 1t 1.Qf3 {10}
78 0.026 -0.02 1. 1.Qf3 {10}
330 0.034 -0.15 2t 1.Qf3 a4 {10}
1136 0.045 -0.15 2. 1.Qf3 a4 {10}
2025 0.054 0.11 3t 1.Qf3 a4 2.Nh6+ Kf8 3.Bxf6 Qxf6 4.Qxf6 gxf6 {0}
3427 0.063 0.11 3. 1.Qf3 a4 2.Nh6+ Kf8 3.Bxf6 Qxf6 4.Qxf6 gxf6 {0}
6708 0.099 0.01 4t 1.Qf3 Nd7 2.Rfd1 a4 {10}
10570 0.107 0.01 4. 1.Qf3 Nd7 2.Rfd1 a4 {10}
16333 0.124 0.08 5t 1.Qf3 Nd7 2.Rfd1 a4 3.Qh5 {10}
25704 0.146 0.09 5t+ 1.Bc4 Qxc4 2.Bxf6 d3 3.Qg4 Rac8 4.cxd3 Qxd3 {0}
31453 0.163 0.26 5t 1.Bc4 Qxc4 2.Bxf6 g6 3.b3 Qc3 {0}
35180 0.173 0.26 5. 1.Bc4 Qxc4 2.Bxf6 g6 3.b3 Qc3 {0}
61596 0.237 0.17 6t 1.Bc4 Qxc4 2.Bxf6 g6 3.Nh6+ Kf8 4.Qd2 a4 {0}
120186 0.390 0.17 6. 1.Bc4 Qxc4 2.Bxf6 g6 3.Nh6+ Kf8 4.Qd2 a4 {0}
188206 0.533 0.31 7t 1.Bc4 Qxc4 2.Bxf6 g6 3.Nh6+ Kf8 4.Qd2 a4 5.Rad1
{0}
279526 0.725 0.31 7. 1.Bc4 Qxc4 2.Bxf6 g6 3.Nh6+ Kf8 4.Qd2 a4 5.Rad1
{0}
459022 1.103 0.25 8t 1.Bc4 Qxc4 2.Bxf6 g6 3.Nh6+ Kf8 4.Qd2 a4 5.Rad1
Rac8 {0}
725340 1.680 0.25 8. 1.Bc4 Qxc4 2.Bxf6 g6 3.Nh6+ Kf8 4.Qd2 a4 5.Rad1
Rac8 {0}
1407664 3.258 0.20 9t 1.Bc4 Qxc4 2.Bxf6 g6 3.Nh6+ Kf8 4.Qd2 a4 5.Rad1
Re6 6.Ng4 Ke8 {0}
3531647 8.268 0.20 9. 1.Bc4 Qxc4 2.Bxf6 g6 3.Nh6+ Kf8 4.Qd2 a4 5.Rad1
Re6 6.Ng4 Ke8 {0}
5560587 13.172 0.17 10t 1.Bc4 Qxc4 2.Bxf6 g6 3.Nh6+ Kf8 4.Qd2 Re6 5.Ng4
h5 6.Qh6+ Ke8 7.Qh8+ Bf8 8.Bg7 Ke7 {0}
13240819 32.555 0.17 10. 1.Bc4 Qxc4 2.Bxf6 g6 3.Nh6+ Kf8 4.Qd2 Re6 5.Ng4
h5 6.Qh6+ Ke8 7.Qh8+ Bf8 8.Bg7 Ke7 {0}
19868019 47.874 0.14 11t 1.Bc4 Qxc4 2.Bxf6 g6 3.Nh6+ Kf8 4.Qd2 Re6 5.Ng4
h5 6.Qh6+ Ke8 7.Qh8+ Bf8 8.Bg7 Ke7 9.Nxe5 Nxe5
10.Bxe5 {80}
69733869 3:10.5 0.14 11. 1.Bc4 Qxc4 2.Bxf6 g6 3.Nh6+ Kf8 4.Qd2 Re6 5.Ng4
h5 6.Qh6+ Ke8 7.Qh8+ Bf8 8.Bg7 Ke7 9.Nxe5 Nxe5
10.Bxe5 {80}
89298000 4:00.4 0.14 12t 1.Bc4 Qxc4 2.Bxf6 g6 3.Nh6+ Kf8 4.Qd2 Re6 5.Ng4
h5 6.Qh6+ Ke8 7.Qh8+ Bf8 8.Bg7 Ke7 9.Nxe5 Nxe5
{-260}
257301734 12:26.0 0.15 12t+ 1.Rc1 Ne7 2.Qf3 Nd7 3.Bxe7 Bxe7 4.Bb5 Bg5 5.Qg3
Kf8 6.Qxg5 g6 {350}
336399294 16:42.0 0.16 12t 1.Rc1 Rec8 2.Qe2 Nd7 3.Qg4 Qg6 4.c3 Nf6 5.Qh4H
Nd7H {HT} {10}
381001784 18:53.5 0.16 12. 1.Rc1 Rec8 2.Qe2 Nd7 3.Qg4 Qg6 4.c3 Nf6 5.Qh4
Nd7 {HT} {10}
809501466 41:28.9 0.10 13t 1.Rc1 Ne7 2.Nxe7+ Bxe7 3.c3 dxc3 4.Rxc3 Rac8
5.Bxf6 Bxf6 6.Qc2 Rxc3 7.Qxc3 Rd8 8.Rc1 Qd6
{HT} {0}
830457245 42:31.4 0.11 13t+ 1.Bc4 Qxc4 2.Bxf6 g6 3.Nh6+ Kf8 4.Qd2 Re6 5.Ng4
h5 6.Qh6+ Ke8 7.Qh8+ Bf8 8.Bg7 Ke7 9.Nxe5 Rc8
{80}
880959982 44:54.9 0.14 13t 1.Bc4 Qxc4 2.Bxf6 g6 3.Nh6+ Kf8 4.Qd2 Re6 5.Ng4
h5H 6.Qh6+H Ke8H 7.Qh8+H Bf8H 8.Bg7H Ke7H {HT}
{0}
1300059964 1:05:47 0.14 13. 1.Bc4 Qxc4 2.Bxf6 g6 3.Nh6+ Kf8 4.Qd2 Re6 5.Ng4
h5 6.Qh6+ Ke8 7.Qh8+ Bf8 8.Bg7 Ke7 {HT} {0}
1439413633 1:12:07 0.12 14t 1.Bc4 Qxc4 2.Bxf6 g6 3.Nh6+ Kf8 4.Qd2 Re6 5.Ng4
Ke8 6.Bg7 Be7 7.b3 Qc5 8.Rfd1 a4 9.Rab1 {0}
1626637479 1:22:08 0.13 14t+ 1.Qf3 Nd7 2.Qg4 Qg6 3.Nh4 a4 4.Nxg6 fxg6
1838182293 1:32:47 0.13 14t 1.Qf3 Nd7 2.Qg4 Qg6H 3.Nh4H Qe6H 4.Qxe6H Rxe6H
5.Bc4H Rd6H 6.Rfd1H a4H {HT} {10}
3648740766 3:07:41 0.13 14. 1.Qf3 Nd7 2.Qg4 Qg6 3.Nh4 Qe6 4.Qxe6 Rxe6 5.Bc4
Rd6 6.Rfd1 a4 {HT} {10}
2777542436 6:10:35 0.16 15t 1.Qf3 Nd7 2.Bd2 Qg6 3.Rac1 a4 4.Bb5 Nb6 5.c3
Rad8 6.Rfd1 Re6 7.Bxc6H {HT} {350}
3075043503 6:25:24 0.17 15t+ 1.Bc4 Qxc4 2.Bxf6 g6 3.Nh6+ Kf8 4.Ng4 h5 5.Qd2
Re6 6.b3 Qa6 7.Nxe5 Nxe5 8.Qh6+ Ke8 9.Bxe5 d3
10.Qh8+ Bf8 {80}
3298093060 6:35:57 0.17 15t 1.Bc4 Qxc4 2.Bxf6 g6H 3.Nh6+H Kf8H 4.Ng4H Re6H
5.b3H Qc3H 6.Ra2H {HT}
1975758719 9:17:10 0.17 15. 1.Bc4 Qxc4 2.Bxf6 g6 3.Nh6+ Kf8 4.Ng4 Re6 5.b3
Qc3 6.Ra2
3187900167 10:17:25 0.17 16t 1.Bc4 Qxc4 2.Bxf6 g6 3.Nh6+ Kf8 4.Ng4 Re6 5.b3
Qc3 6.Qc1 Kg8 7.Rd1 Be7 8.Rd3 Qc5 9.Rf3 Bxf6
10.Nxf6+ Kh8 {HT} {0}
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.