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Subject: Re: Junior 5 - Crafty 15.17 40/120 games

Author: Serge Desmarais

Date: 03:55:39 08/29/98

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On August 28, 1998 at 23:47:30, Robert Hyatt wrote:


>
>
>the real problem is to be a pawn down, with a nice lead in development, and
>then suddenly find a way to win a pawn but give up the positional advantage in
>doing so...  then it ends up left with a ragged position, maybe equal material,
>and loses the endgame in a slow grind...
>
>Or, if you remember the DB vs Kasparov game 6, an IM tried that position against
>a couple of the top commercial programs last year, with the IM playing black,
>and he won all games easily.  Because the programs would invariably find a way
>to "cash in" and get a little material back, but black ends up a piece ahead
>and the win is easy if white's attack fizzles.  This is what makes playing such
>openings so very difficult..  As a human, when attacking, after tossing a pawn
>or even a piece, I'm not looking to win a pawn (or the piece) *back*...  I am
>looking for much more... something programs often don't grasp...
>
>But one day, maybe they will..  the thing that helps is great search depth, so
>that it can "keep the win of material in sight" but still carry on the attacking
>plan...  I've seen much better results as depth has increased.  In the old days,
>doing 6-7 plies, such problems were serious, because that's not much horizon to
>both win material *and* keep up the attack.  At today's 10-12 plies, the
>programs can do better.  But not as good as they will at 15-16-18 plies in the
>future...


   That is understandable. But I am under the impression that more and more PC
programs are becomming less materialistic. For example, Fritz 5 often gives
pawns. For example, if a pawn it threatened of capture and defending it would
mean bringing the pieces back behind the lines and having a somewhat cramped
position, it would often let go the pawn and to keep active pieces play and try
to make threats directly at the opposing king. Of course, it too had to suffer
and slowly die in a long ending a few times. But sometimes it works and it would
win, or at least obtain a draw because of sufficient compensations.


   One major problem I found that happens in several programs is in endings with
all pawns on the same side while being a piece down (say K+R+3P vs K+R+B+2P).
And when the opponent would offer a rook trade, they would go for it!. Fritz,
did it while at 17 plies. What is strange is that almost IMMEDIATELY after the
trade, the eval drops damatically below what it was a lot deeper before the
trade! I have seen similar things in Genius too (trading queens to remain with
K+pawns vs K+pawn(s)+B! With a piece down, the opponent can take the opposition
at will with a B or N's move! As for PC programs, they are now much better than
me at finding counterplay and evaluating compensations for material invested, it
seems. (I am just about a 1800-1900 USCF player - rated over 1680 here in Quebec
and as I know one must add between 100 to 200 points to translate our ratings in
USCF). I admit I have much more trouble playing against tactical and aggressive
programs like Fritz, Crafty etc. than playing quiet ones, like Genius, agaisnt
which I am able to draw from time to time at 40/2 (when I succeed in bringing
positions with opposite colour bishops etc.). But against the tactical fast
searchers (aggressive?) it is tough to even pass the 30th move without being at
a disadvantage!


Serge Desmarais



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