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

Author: Vincent Diepeveen

Date: 10:15:16 08/11/99

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On August 10, 1999 at 18:42:58, Tom King wrote:

>On August 09, 1999 at 20:41:50, Robert Hyatt wrote:
>
>>On August 09, 1999 at 17:51:01, Tom King wrote:
>>
>>>On August 08, 1999 at 21:35:46, Robert Hyatt wrote:
>>>
>>>[snip]
>>>>
>>>>
>>>>I've been doing a 'hybrid' for nearly a year...  R=3 fairly close to the
>>>>root, R=2 beyond some threshold that I don't remember what it is...
>>>>
>>>>
>>>
>>>Interesting.. better than pure R=2 or pure R=3? I did some experiments a while
>>>back, using R=3 on the opponent's move, and R=2 on the computers move (idea
>>>being - let's not cover up the opponent's threats, and if we miss some of our
>>>threats, well, so be it). But it was more or less a 'wash'.
>>
>>
>>I started playing with this after Paris, as someone said that Frans (or someone)
>>was fiddling around with R=3.  Bruce and I played a few games one night with
>>Ferret vs Crafty, with bruce using R=3, and we saw _no_ gross mistakes on his
>>part.  In fact, we couldn't tell the difference (at least R=3 was not making
>>mistakes that R=2 wasn't).
>>
>>But I never felt comfortable with raw R=3, as R=2 causes more than enough
>>problems already, thank you very much.  :)
>>
>>Ernst is writting an ICCA paper describing some experiments he did with this
>>(totally unconnected with my tests).  Wait for his paper to hit the journal as
>>he has some good data...  And I am not yet sure that this is a good idea, but I
>>have been running it a good while and it has been in the distributed Crafty for
>>quite a while as well and no one has complained.  Of course, now that everyone
>>knows, look out.  :)
>
>One thing's for sure - I'm sure there's a lot more we could all be doing with
>the null move. Playing around with different values of R, depending on depth in
>the tree, alpha and beta etc. etc. I look forward to this paper. Ernst has been
>productive of late..I'm sure I'm not the only one to enjoy reading his articles.
>[even if his damn program does kill mine at the WCCC ;-)]

i did for many years first nullmove R=3 then R=2 (since 1995 i toy
with this), and it solved many tricks for me in the known testsets.

However practically R=3 always gives more speedup so
i'm using everywhere R=3 now.
>Cheers,
>Tom.



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