Author: Robert Hyatt
Date: 14:40:22 10/13/98
Go up one level in this thread
On October 13, 1998 at 17:01:51, Moritz Berger wrote:
>On October 13, 1998 at 15:56:09, Robert Hyatt wrote:
>>On October 13, 1998 at 13:04:02, Moritz Berger wrote:
>>
>>just so you know, some of these are openings Crafty is *not* going to
>>play very well, most likely, unless the "cramped pawns and blocked
>>position" code is working better than I thought. :)
>
>So far, Crafty has been doing quite well (50%), despite some games with wrong
>settings for Crafty (which will be repeated after the 10th Nunn position). That
>some openings are not well suited for computers is intended in the Nunn test as
>far as I understand it - measuring progress where it is needed most seems to be
>a good thing for such a test.
>
>>this is one example, although I haven't looked at the precise variation to
>>see how the position starts off... and how did crafty draw the first game
>>with an eval of -6.something? that ought to be lost? Could the result
>>tag be wrong somehow?
>
>In the Fritzian universe, eval -xx.yy means: advantage for black (as opposed to
>eval xx.yy = good for white). Crafty scores are parsed by Fritz, so
>
>{0.05/12 428}
>
>translates to:
>- 0.05 advantage for white
>- eval at 12 ply
>- after 428 seconds, not taking into account time spent on that position in
>permanent brain
>
>Position at move 73. (white to move) in the drawn game
>(FEN: 8/4k1K1/6r1/4n3/8/8/7R/8 w - - 0 73) is a draw per KT-EGTB.
>Indeed, after move 116 we still have 5R2/6r1/7K/4n3/4k3/8/8/8 b - - 0 116 and no
>progress has been made. So I adjudicated it a draw.
>
>Why the -6.something score from Crafty? Crafty 15.19 engine for Fritz uses
>different opening book and EGTB mechanisms than wcrafty or linux-crafty:
>
>- The Fritz UI controls the opening book. When it leaves the book, it hands over
>to the active engine (Hiarcs, Junior, Fritz, Crafty, Exchess, Nimzo,
>CD-Endgame).
>
>- per move timing is *not* controlled by the Fritz UI but by the engines
>themselves - they are initialized with proper time controls at the beginning of
>each game, but then left alone.
>
>- Endgames are either done by selected "playing" engines or "CD-Endgame" engine
>(that is selected automatically if you select that option (default) and only
>probes some 5 man KT-EGTB at the root).
>
>Obviously, there's no crafty.rc or any other way to pass parameters to the
>Crafty engine other than using the engine-parameters dialog with options offered
>by the UI, namely (for Crafty 15.19): "no tricks" and "draw score normal".
>
>I remember reading a statement from Bob that Crafty would suffer if it didn't
>have it's own book. I have played several dozens of Blitz (60/5) games
>Crafty15.19/PII-450 vs. Hiarcs6/P233MMX and Crafty scored about 50% with the
>FritzPower book.
>
>Why the "good" result? The reason is simply that the Fritz PowerBook doesn't
>contain any Fritz-specific weightings but only move frequency, performance
>percentage and ELO-performance plus learning-adjusted weightings (learning is
>also not done by the engine but by the UI, using engine evals for guidance). So
>the Fritz PowerBook concept works equally well for all engines because the
>learning-values are all 0 before the 1st game.
>
>Do you have any more questions I didn't answer?
>
>I feel that if Crafty gets 50% in the Nunn test or in Blitz games against Hiarcs
>and if Crafty has a PII-450 vs. P233MMX for its opponent, this still shows that
>Crafty is very likely not weaker than 100 SSDF-ELO than the top commercial
>programs - after all, as Fritz engine it doesn't get it's own book (doesn't
>matter in the Nunn test, of course), it doesn't get full EGTB support and
>doesn't have its own positional learning. I think the result shows that Crafty
>is a serious, strong chess program and this is exactly the reason why I also
>enjoy it for consultation in ChessBase 7, not only as an opponent to play
>against. Remember how "well" another program recently did against Hiarcs 6 in
>the Nunn test with the same hardware handicaps against Hiarcs ...
>
>Moritz
ok... the - eval now makes sense... This is the way crafty normally annotates
a game on its own, too, but I didn't stop to look at a position... although I
now need to look at the game to see why it couldn't win a +6 ending...
And I wasn't questioning what you are doing. But some openings don't work. For
some programs...
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