Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Conspiracy -- conshmiracy

Author: Dann Corbit

Date: 20:19:41 01/20/00

Go up one level in this thread


On January 20, 2000 at 22:23:15, Michael Neish wrote:

>On January 20, 2000 at 02:18:51, Ed Schröder wrote:
>
>>You misunderstand. It's the DB main-line for 36.axb5 what made Kasparov
>>suspicious. In this main-line DB sacrificed 3 pawns for no direct win
>>but for a dangerous looking king attack, all very human-like. Kasparov
>>could not believe his eyes (he still can't) and started the accusation
>>human intervertion took place as he could not believe a computer was
>>able to produce such a (super) main-line.
>>
>>So this whole issue is NOT about the move 36.axb5 but about the asthonising
>>main-line DB produced.
>
>Ed, out of interest, do you happen to know what was the line that DB came up
>with?  Was it the same as what was played in the actual game?
>
>I just did what a lot of you must have done: I set my pet program thinking on
>the position where DB chose 36. axb5.  In this case I'm using HIARCS 7.  This is
>probably very naive, but at 8-ply the score for 32. Qb6 and 32. axb5 was almost
>the same.  At 9-ply though it favours Qb6 quite clearly (about +1.7, compared to
>+1.0 for axb5).  Maybe the key points in the search lie at deeper plies?  Can
>anyone tell me what a program should be able to spot in order to determine that
>axb5 is the best move?  And has it been proven beyond doubt by grandmaster
>analysis that axb5 is best?
>
>Not trying to prove a point either way.  Just interested.

Kasparov was very, very unhappy that the computer chose axb5.  Since he is the
strongest player in the world, I think that is a very good indication that DB
chose the right move.

With computer analysis, you will never know if the right move was chosen or not,
unless you do an exhaustive search without null move all the way to checkmate.
Hyatt & Heinz both did "goes deep" experiments that show no matter how deep you
look, you never stop finding improvements.  And each new ply is of approximately
the same value as the one before it (but much harder to calculate).

GM's, also, can be wrong in their analysis.  So what is the best move from some
board position?  Nobody knows.  On the other hand, you *can* rigorously say that
for an examination of all the positions up to n plies forward, some move is
better than others (assuming you can come to agreement on how to calculate
piece, positional, and other value factors consistently).




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.