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Subject: Re: Schröder's new web page

Author: Vincent Diepeveen

Date: 10:19:33 12/30/02

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On December 30, 2002 at 02:20:53, Uri Blass wrote:

In this case test it before shouting about it.
i assume you throw nullmove out of movei and then
look whether you get 15% with it?

>On December 28, 2002 at 19:03:33, Tony Werten wrote:
>
>>On December 28, 2002 at 16:03:46, Uri Blass wrote:
>>
>>>On December 28, 2002 at 15:39:08, Tony Werten wrote:
>>>
>>>>On December 28, 2002 at 14:17:17, Alessandro Damiani wrote:
>>>>
>>>>>[snip]
>>>>>
>>>>>>
>>>>>>the problem of most 'reductions' is the hard fact that you lose a full ply
>>>>>>near the root.
>>>>>
>>>>>That's why reductions are not done in every node, but under certain conditions.
>>>>>The quality then depends on those conditions, of course. Therefore, reductions
>>>>>are not bad per se.
>>>>
>>>>This was about recursive reductions as FHR. What happens is at a ply you decide
>>>>to reduce depth, but 2 ply later, the conditions are still met and you reduce
>>>>another ply etc.
>>>>
>>>>I dumped them because they cost to much tactical strenght. Ed's nonrecursive way
>>>>seem to give me a 5% node reduction. Not bad for 2 minutes work.
>>>>
>>>>Tony
>>>
>>>The question is still if it does not cost too much tactical strength.
>>>
>>>It is not clear if being 5% faster in 95% of the cases and seeing tactics one
>>>ply later in 5% of the cases is a good idea.
>>
>>I had no case where I saw tactics one ply later. But then again, I didn't have
>>the 15% speedup Ed mentioned either.
>>
>>Personally, I think I prefer the "safe" 5%.
>
>I believe that more than 5% can be gained and the point is that if you get only
>5% you need to check a lot of positions to verify that seeing tactics one ply
>later is rare enough to justify pruning.
>
>I believe that better conditions can be used for reduction and the gain should
>be more than 15%.
>
>I did not test it in movei because I already have different rules of pruning
>based on evaluation.
>
>Uri



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