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Subject: Discrepancy between score and PV

Author: Normand M. Blais

Date: 20:53:48 07/21/03

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#

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Last modified: Thu, 15 Apr 21 08:11:13 -0700

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