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Subject: Re: The King's News Clothes (Re: DB vs)

Author: Robert Hyatt

Date: 17:13:16 11/23/98

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On November 23, 1998 at 18:47:20, Amir Ban wrote:

>On November 23, 1998 at 17:14:28, Robert Hyatt wrote:
>
>>On November 23, 1998 at 11:50:01, Amir Ban wrote:
>>
>
>>I'm going to try to keep this simple.  Here is a point-blank question:  if you
>>really believe that nonsensical statement you wrote above, then how can you
>>reconcile that with a program that is searching at least 1,000 times faster
>>than you, yet only gets to depth 10-11 in the game?  If they are not extending
>>far more than you could ever hope to then exactly *what* are they doing with
>>that factor of 1,000?  And remember that they have a pretty simple quiescence
>>search and they toss out bummer captures as well, so the work is *not* in
>>looking at zillions of captures.
>
>Seems like you misunderstand another side of this, because you are mistaking me
>for a null-mover.
>
>To get to nominal ply 11, I would have to search at least to my (half-ply) depth
>21. If you've ever seen Junior play, you know that that's a lot for a middlegame
>position. I'm guessing it will take Junior at least a few days to get there.
>
>When I do get to that depth, though, I expect to see much more than Deep Blue
>sees at its ply 11, because I'm much more heavily extended, and of that, I'm
>sure.
>
>Amir

That's my question, however.. They are *only* getting to ply 11.  I can get to
ply 10 with crafty with null-move *off*.  searching under 300K nodes per second.
So what do you suppose *they* are doing with that factor of 1,000 nodes?  Must
be something *very* serious...  IE I saw *Socrates "outsearch" deep thought by
a ply or two in Cape May (if you look at depth reported on the screen).  And
Deep Blue isn't going any deeper today it seems.  So those nodes are going
*somewhere* and the only place I can figure is extensions...  They have always
been liberal (ie they allow 1 ply of extensions for *every* ply in the search
if you read their JICCA paper.  You can't go beyond that and have a search that
terminates... and even 1:1 is on the ragged edge...

That was my only point here...  that they follow some things *very* deeply.
I sometimes see 24 ply variations from Crafty on a 12 ply search.  But when
I watched Deep Thought I saw many 30+ ply variations in tactical cases, and
that doesn't touch the last 4-5 plies + captures that don't get displayed...




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