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Subject: Re: In the generate_move function...

Author: Nicolas Carrasco

Date: 07:26:14 12/21/99

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You conviced me to put SEE before MVV/LVA. I will make stats and I someone is
interested I will publicate them.

On December 21, 1999 at 09:56:31, Robert Hyatt wrote:

>On December 21, 1999 at 06:45:01, Daniel Clausen wrote:
>
>>Hi
>>
>>On December 21, 1999 at 00:36:03, Robert Hyatt wrote:
>>
>>>On December 20, 1999 at 13:02:38, Nicolas Carrasco wrote:
>>>
>>>>Do u know any documentation of MVV and LVA?
>>>
>>>This approach (MVV/LVA or Most Valuable Victim, Least Valuable Attacker)
>>>was designed for hardware move generators, as this is easy to do with some
>>>parallel hardware for each square.  It works OK for normal chess programs,
>>>although SEE is generally better.
>>>
>>>It just means (a) find the most valuable piece that is attacked by the
>>>moving side, and then (b) capture it by the least valuable piece that is
>>>attacking it.
>>>
>>>Very simple to implement.
>>
>>This is what I'm also doing in my engine now. I noticed though that in
>>my case it's better to try the loosing capture also before the quiet
>>moves. I'm not sure whether this has to do with the relatively bad
>>quality for the MVV/LVA-value (compared to the SEE-value) or caused
>>by yet another silly mistake somewhere in my engine.
>>
>>Kind regards,
>> -sargon
>
>
>This is only true with MVV/LVA.  Because it doesn't recognize 'losing' captures
>very well.  QxR is not losing, if the queen has a bishop behind it, backing it
>up, and the rook is defended by a rook.  So that QxR, RxQ, BxR is played.  That
>wins a pawn.  SEE would correctly recognize that this wins material and try
>it before moves like RxR which might (by MVV/LVA) either win a rook or be an
>even exchange.
>
>Once you add SEE, you can put off losing captures to the very end.



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