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Subject: Re: SEE for forward pruning in Q. Search

Author: David Blackman

Date: 03:02:59 08/11/99

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On August 10, 1999 at 21:55:29, Robert Hyatt wrote:

>If you want to play around, here's another idea I have on my 'to-do' list:
>
>at present I 'break' the search into two 'chunks'.  the part near the root
>uses R=3, the rest uses R=2. Something tells me this might be made much more
>dynamic than that...  ie R=4, then 3, and finally 2.  But rather than some
>static divisor as I have now, make this dynamic so as you go deeper, you use
>bigger R values near the root, etc...
>
>Seems reasonable.  Whether it will work or not, we won't know until we try
>it...

I tried this when i first heard vague rumours about null-move, before i heard
about the R=x thing. I think the null search was at half the depth of the main
search (instead of depth-R-1 which is the normal way). Hard to say if it helped
since the rest of the program was quite weak and i didn't get much depth anyway
in those days.

Another thing i tried was to always do the null-move to a fixed depth, like
maybe 3 ply. This sometimes allowed really impressive search depths, but of
course it can get into serious trouble by missing tactics that start with an
apparently non-threatening move. Overall it was a loser. But i am thinking of
trying this again in combination with some other ideas to limit the damage ...



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