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Subject: Re: Why ... egtb format ...

Author: Anthony Cozzie

Date: 10:52:02 04/02/04

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On April 02, 2004 at 02:13:53, Johan de Koning wrote:

>On April 01, 2004 at 22:30:27, Eugene Nalimov wrote:
>
>>I see. So in FEG your have krpkr wtm, krpkr btm, krkrp wtm, and krkrp btm. Than
>>yes, you can figure value without the search, at a cost of (probable) extra TB
>>probe. Extra probe is unavoidable when the score is a draw.
>
>As Uri pointed out, one can easily avoid these extra probes inside
>an alpha-beta search.
>
>But as Theron pointed out some years ago, one should avoid *any*
>probe inside a search.
>
>>So your are paying that price, and slower access due to 4x larger block size, to
>>achieve ~30% smaller TBs. Reasonable tradeoff, but I would not call it "better"
>>:-)
>
>Decompression time is tiny compared to random disk access, and it is
>getting tinyer all the time. Hence when we're talking about 20% smaller
>(rather then 30% !) it's not a trade-off but simply a small advantage.
>
>When it comes to "better", there is the simple fact that FEG generates
>the data [BLEEP]ingly fast. On any machine. Without the need to update
>whenever some Pawn is added to whatever side.
>
>Please accept that fact and don't play stupid (or should I say don't
>play MicroSoft?). Though my social intelligence is close to retarded,
>I can't help sensing friction eversince we met (Maastricht 2002).
>I'm trying to ignore it, and letting it be your problem. But as you
>can see, sometimes I fail to ignore it. Let's just say Nalimov TBs
>are cool and FEG is cool, OK?
>
>>BTW you can achieve better compression in .emd files by replacing all "broken"
>>scores by the most common non-broken score in the TB. I always was curious how
>>much it will save, but never made the experiment...
>
>Do the experiment and be surpised. Surprised by the fact it doesn't
>save much. Surprised by the fact that, given a suitable symbol size,
>statistical compression works much better than intuition. Well, we
>knew that already. But still it is scary. :-)
>
>... Johan

For those of us that don't want to spend 1 year writing good interior node
recognizers, the Nalimov TBs & free code are great :)

anthony



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