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Subject: Re: Some analysis of Deep Fritz for kasparov-deeper blue first game

Author: Uri Blass

Date: 12:10:13 05/07/01

Go up one level in this thread


On May 07, 2001 at 14:29:05, Robert Hyatt wrote:

>On May 07, 2001 at 12:40:22, Uri Blass wrote:
>
>>
>>For me difference of more than +2 in the evaluation of Deeper blue and Crafty is
>>convincing.
>>
>>I am not talking about the difference of 1.7 and 1.4.
>>There is even a difference of more than 1 pawn between Deep Fritz's evaluation
>>and Crafty's evaluation but Fritz can find the right pv.
>
>Just listen to what you just said.  There is a difference of more than one pawn
>but DF has the right PV.

Difference of more than 1 pawn is not difference of more than 2 pawns and the
difference between Deeper blue and crafty was of more than 2 pawns.

Difference of more than 1 pawn can be a result of different evaluation but
difference of more than 2 pawns is usually result of tactics.


  With DB you can _not_ see the PV.  The first moves
>are probably reasonable.  The moves at the end might or might not be reasonable,
>and the last 6 plies + extensions + captures are not seen _ever_.

I mean to the second move in the pv that is not at the end of the pv and is
almost the start of the pv when I say that deep blue has not the right pv
Rf5+ Ke2... is the wrong pv of deeper blue.

Rf5+ Ke3... is the right pv after Rf5+.
>
>Which simply shows that you can _not_ compare DB to _anything_ without all the
>information...
>
>
>
>
>>
>>I cannot say 1.7 of Crafty is better than 1.4 of Deeper blue but I can say that
>>4.x of Crafty and 3.x of other programs are better than 1.x of deeper blue and
>>the evaluation of deeper blue was 1.x if you look at depth 15(the depth that
>>Crafty found the line with Ke3)
>
>Count the pieces on the board, then look at king safety, and everything else.
>Then you can _guess_ at what DB was evaluating compared to Crafty and the other
>micro programs.  But you can only _guess_.  You are assuming they are seeing
>_less_.  What if they are seeing _more_???  How can you tell they aren't?  You
>can't.  It is _all_ a guess...
>
>
>
>
>>
>>I am almost sure that Crafty can beat Deeper blue if Crafty searches the same
>>depthes that deeper blue searched and my guess is that Crafty on an alpha is
>>clearly better than deeper blue.
>>
>>Uri
>
>
>Not a chance.  It would be competitive, but only competitive, in that it would
>not get run off the board in a match.  It would lose decisively however...
>
>I ran a 10 game set vs Cray Blitz about a year ago (right after I first got the
>quad xeon).  I did it as a favor for someone wanting to test a T90 for
>comparison to something I can't mention.  I played the games at a time control
>of 60 moves in 30 minutes.  Cray Blitz won 6 and drew 3.  There were only a
>couple of games that were tactical busts...  most were just endgame losses where
>the Cray searched incredibly deep with its speed advantage...
>
>I call that a pretty decisive result.  And that same program got stomped by the
>predecessor of Deep Blue.

There was only one game when Cray blitz with no bugs lost and one game proves
nothing.

Uri



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