Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: An exchange sacrifice...

Author: Jeremiah Penery

Date: 18:03:46 08/24/04

Go up one level in this thread


On August 24, 2004 at 00:23:38, Eric Jensen wrote:

>I have recently come across the following position,
>
>/r5k/pp2qppp/2b/n/2pPr/P1P1PQ1P/1B4P/1B2RRK/
>
>with white to move.  It will be white's 21st move.  I have let crafty run and
>analyze this position for over 2 hours, and it returns a value of over +2 for
>white.  However, I don't think that crafty understands the position, because
>I've had it sort of play against itself (I was using SCID for analysis, and
>pulled up the engine analysis with crafty) by making it's best move for each
>side after about a min or so each time, and it routinely wins with black.
>
>I would be interested to see a Deep Position evaluation of hte position from
>Shredder or Junior or something Stronger than Crafty, but also I would be
>interested in seeing games from a short engine match with this start position,
>just to see if the evaluations can be trusted.

I have an old modified Crafty I made and this is what it tells me:

Modified Crafty 19.1(?), AthlonXP 1900+

           10     7.34  -0.06   1. Bxe4 Bxe4 2. Qg4 b5 3. Kh2 Nb3 4.
                                Rd1 f5 5. Qf4 Qb7
           10->  20.53  -0.06   1. Bxe4 Bxe4 2. Qg4 b5 3. Kh2 Nb3 4.
                                Rd1 f5 5. Qf4 Qb7
           11    28.25  -0.03   1. Bxe4 Bxe4 2. Qh5 Nb3 3. Rf4 Bxg2
                                4. Qxf7+ Qxf7 5. Rxf7 Kxf7 6. Kxg2
                                Rf8
           11    50.62   0.18   1. Qf5 g6 2. Qf6 Re6 3. Qxe7 Rxe7 4.
                                e4 Rae8 5. Rf4 Nb3 6. Kh2 <HT>
           11->  59.20   0.18   1. Qf5 g6 2. Qf6 Re6 3. Qxe7 Rxe7 4.
                                e4 Rae8 5. Rf4 Nb3 6. Kh2 <HT>
           12     1:16   0.05   1. Qf5 g6 2. Qf6 Re6 3. Qxe7 Rxe7 4.
                                e4 Rae8 5. Rf4 Nb3 6. Bc2 Nd2
           12->  17:16   0.05   1. Qf5 g6 2. Qf6 Re6 3. Qxe7 Rxe7 4.
                                e4 Rae8 5. Rf4 Nb3 6. Bc2 Nd2
           13    18:30   0.29   1. Qf5 g6 2. Qf6 Qxf6 3. Rxf6 Re6 4.
                                Rxe6 fxe6 5. Bc2 Nb3 6. Rf1 Kg7 7.
                                Kf2 Rf8+
           13->  20:24   0.29   1. Qf5 g6 2. Qf6 Qxf6 3. Rxf6 Re6 4.
                                Rxe6 fxe6 5. Bc2 Nb3 6. Rf1 Kg7 7.
                                Kf2 Rf8+
           14    25:56   0.24   1. Qf5 g6 2. Qf6 Qxf6 3. Rxf6 Re6 4.
                                Rxe6 fxe6 5. Bc2 Rf8 6. Rf1 Nb3 <HT>
           14->  76:39   0.24   1. Qf5 g6 2. Qf6 Qxf6 3. Rxf6 Re6 4.
                                Rxe6 fxe6 5. Bc2 Rf8 6. Rf1 Nb3 <HT>
           15   103:16   0.21   1. Qf5 g6 2. Qf6 Qxf6 3. Rxf6 Re6 4.
                                Rxe6 fxe6 5. Rf1 Nb3 6. Rf6 Bd5 7.
                                Kf2 Kg7 8. Rf4 Rf8 9. Rxf8 Kxf8
           15-> 126:49   0.21   1. Qf5 g6 2. Qf6 Qxf6 3. Rxf6 Re6 4.
                                Rxe6 fxe6 5. Rf1 Nb3 6. Rf6 Bd5 7.
                                Kf2 Kg7 8. Rf4 Rf8 9. Rxf8 Kxf8
           16   150:59   0.24   1. Qf5 g6 2. Qf6 Qxf6 3. Rxf6 Re6 4.
                                Rf4 Rae8 5. e4 Nb3 6. Bc2 f6 7. Ref1
                                Nd2 8. d5 Nxf1 9. dxe6
           16-> 384:17   0.24   1. Qf5 g6 2. Qf6 Qxf6 3. Rxf6 Re6 4.
                                Rf4 Rae8 5. e4 Nb3 6. Bc2 f6 7. Ref1
                                Nd2 8. d5 Nxf1 9. dxe6
           17   489:20   0.20   1. Qf5 g6 2. Qf6 Qxf6 3. Rxf6 Re6 4.
                                Rf4 Rae8 5. e4 Nb3 6. Kf2 f6 7. Rd1
                                g5 8. Rf5 g4 9. d5
           17-> 895:44   0.20   1. Qf5 g6 2. Qf6 Qxf6 3. Rxf6 Re6 4.
                                Rf4 Rae8 5. e4 Nb3 6. Kf2 f6 7. Rd1
                                g5 8. Rf5 g4 9. d5

           18   1153:45   1/29?  1. Qf5


      Elapsed Time: 1153:46, CPU Time: 1147:59, CPU Use: 99%
      Nodes: 24858365339, Evaluations: 2148216470, FH%: 93%, NPS: 359k
      EXTENSIONS->
          Threat: 6692782, Check: 1518216461, One Move: 101030902
          Passed Pawn: 23606622, Recapture: 59761629
      PRUNING->  Futility: 4275534194, Razors: 570384065
      TABLEBASES-> Probes: 0, Successful: 0
      HASHING->
          Raw Hits: 244% (418072557/171069176)
          Good Hits: 243% (416987868/171069176)
          Pawn Hits: 96% (2074248611/-2146750794)
          Filled: 99%
          EXACT Hits: 0% (622)
          LOWER Hits: 197% (337512962)
          UPPER Hits: 45% (77621640)



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.