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Subject: Re: Please stop the bickering

Author: Robert Hyatt

Date: 10:45:40 10/29/99

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On October 29, 1999 at 12:54:51, Robert Hyatt wrote:

>
>Sorry... but not even close.  I have used null move since 1989, when Don Beal
>wrote the JICCA paper "Selective search without tears" which was a detailed
>description of the null-move approach".  A bit more than 5 years if my math is
>right, and _not_ a commercial programmer.  When we were getting ready (and I am
>not sure about the exact time) for an ACM event, Burton Wendrof pointed out this
>to me (I am not even sure it was in the JICCA now that I think about it) and
>sent me a copy.  I added the code with 10 minutes work (I used R=1 to start
>with, Beal mentioned R=2, but it seemed unsafe to me at the time).
>
>Where does the 'commercial programmer' angle you mention come from?
>
>


I thought about this some more.  I now remember the name of Murray Campbell's
paper which was "Some experiments with the null-move search".  This was _the_
paper on the classic null-move search, and was written while Murray was at
the University of Alberta, which means prior to chiptest/deep thought, which
first played in 1986.  So somewhere around 1985-1987 is the time when null-move
search became generally known.  Murray explained the algorithm, the overhead,
and even discussed R=2 but mentioned that at 198x speeds (whatever that was)
it was not certain that it was safe to use without having to accept severe
tactical mistakes.  I believe "Selective search without tears" came out before
this (Don Beal author) as Murray attributed the original idea to Beal.

I think the main new thing that came out in Chrilly's paper was the "null-move
threat extension" defined in the section "the program that knew too much".  But
this was hardly the first publication about null-move.  This came out after
Crafty was already running IIRC.  And Crafty had null-move in version 1.2,
which was inside the first month of its development.  Version 3.4 included the
null-move threat extension mentioned by Chrilly.  Which stayed in for several
months before being discarded.




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