Computer Chess Club Archives




Subject: Re: When to do a null move search - an experiment

Author: Robert Hyatt

Date: 20:34:57 04/29/04

Go up one level in this thread

On April 29, 2004 at 23:26:12, Dave Gomboc wrote:

>>>>No of course not, brute force is silly, Rebel since day 1 has been a selective
>>>>program. But I am getting your point, in the days before the nullmove was
>>>>discovered Genius and Rebel had the best (static) selective search, a dominant
>>>>factor in their successes, is that what you meant to say? If so, it is true.
>>>>If only Frans had kept his mouth shut to Chrilly (Chrilly leaking nullmove in
>>>>the ICCA journal) it is very likely Fritz would been the next Richard Lang still
>>>>dominating all the rating lists and WCC's for the last decade. But Frans didn't
>>>>and then all bets were off.
>>>Donninger published the article in 1993. Before that, there were two other
>>>publications dealing with null-move:
>>Yes, nullmove as we use it today, the other 2 articles not.
>>>Beal, D.F. (1989). Experiments with the null move. Advances in Computer Chess
>>>5, (Ed. D.F. Beal) , pp. 65--79.
>>>Goetsch, G. and Campbell, M.S. (1990). Experiments with the null-move heuristic.
>>>Computers, Chess, and Cognition, (Eds. T.A. Marsland and J. Schaeffer), pp.
>I think that while Chrilly Donninger's article was important, if it had not been
>published the idea would have been discovered and published later anyway.  The
>question is how much longer would it have taken to become public knowledge?  Of
>course, we can never know, but given that people were doing experiments with the
>null move already I don't think it would have taken a whole decade.

I was doing null-move in 1989-1990 after receiving a draft of Campbell's paper
from Burton Wendroff (lachex).

I used R=1, although Campbell's paper specifically mentioned R=2 as a test that
needed to be done.

Chrilly's paper was more about the null-move threat detection, if I recall the
paper, as that part was a new idea (doing a null-move and seeing if it failed
low badly but a real move failed high normally, suggesting that this is a
position where there is a forced move to hold off a serious threat, something
that needs to be searched deeper).

I believe I still have the hardcopy of the draft of the paper I received.  I
don't have dates, but based on version numbers in my old CB hard copy, it
appears that null-move was added prior to the 1989 wccc event after I saw this
paper.  I also have a draft from that same time period of the first singular
extensio paper they wrote...  I didn't implement that for several more years

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