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Subject: Re: node explosion

Author: Robert Hyatt

Date: 16:31:12 08/22/05

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On August 22, 2005 at 18:37:26, Eugene Nalimov wrote:

>On August 22, 2005 at 17:40:38, Robert Hyatt wrote:
>
>>On August 22, 2005 at 15:50:15, David Dahlem wrote:
>>
>>>What is the most likely cause of a huge node explosion at depth 10, with a
>>>branching factor of 24?
>>>
>>>I'm getting 72% move ordering with this order...
>>>
>>>1. Best move in previous ply
>>>2. Winning captures
>>>3. Killer moves
>>>4. Neutral captures
>>>5. Bad captures
>>>6. Rest of the moves
>>>
>>>Thanks for any clues
>>>Dave
>>
>>
>>A pathological case.
>>
>>For example, you search to depth N, and you get all the move ordering stuff set
>>for that tree, then you search one ply deeper and discover everything changes,
>>and what was a good move in the last search is now horrible because you are
>>seeing some tactics you were overlooking at one ply less.
>>
>>This doesn't happen that often, but it does happen, and there's nothing you can
>>do since you can't tell that ordering is screwed up until after the fact...   :)
>
>Internal iterative deepening may help in such cases.
>
>Thanks,
>Eugene


Perhaps, although I don't use it there.  Only when I seriously need a good move
and the hash table comes up empty...



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