Null move question & using the main TT in qsearch ?

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MahmoudUthman
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Null move question & using the main TT in qsearch ?

Post by MahmoudUthman »

*First regarding the null move , why is it bad to descend directly to the Q-Search on the wiki I found this
It is debatable whether a programmer should allow the null move search descend directly to the quiescence search. Most probably it is worthwhile only with more tactically aware versions of quiescence.
but what is the definition of "a more tactically aware" ? what else to consider than captures + promotions ?

*Second : is it okay to use the main transposition table in the Q-Search or should I use a separate one ?

*by the way I don't limit the depth of the Q-Search "in case it makes any difference"
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Evert
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Re: Null move question & using the main TT in qsearch ?

Post by Evert »

MahmoudUthman wrote:*First regarding the null move , why is it bad to descend directly to the Q-Search on the wiki I found this
It is debatable whether a programmer should allow the null move search descend directly to the quiescence search. Most probably it is worthwhile only with more tactically aware versions of quiescence.
but what is the definition of "a more tactically aware" ? what else to consider than captures + promotions ?
Checking moves.
*Second : is it okay to use the main transposition table in the Q-Search or should I use a separate one ?
Using a separate one is probably a bad idea, because it's just another thing competing for cache space. Some don't use the transposition table at all in q-search.
Best to just try both and see what works best for you.
MahmoudUthman
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Re: Null move question & using the main TT in qsearch ?

Post by MahmoudUthman »

I don't understand what is wrong with checking moves in Qsearch ? does this hold even if I don't return early using the stand pat score in case of check ?
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cdani
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Re: Null move question & using the main TT in qsearch ?

Post by cdani »

MahmoudUthman wrote:I don't understand what is wrong with checking moves in Qsearch ? does this hold even if I don't return early using the stand pat score in case of check ?
Analyzing checking moves on the first level of qsearch works pretty well, as very often there are tactics involved with them. But not on next levels as the tree explodes quite easy.
Ferdy
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Re: Null move question & using the main TT in qsearch ?

Post by Ferdy »

MahmoudUthman wrote: but what is the definition of "a more tactically aware" ? what else to consider than captures + promotions ?
Other moves to consider:
1. A non-capture checking move
2. A non-capture pawn move to 7th rank
3. A non-capture pawn move that forks opp knight and rook
4. A non-capture pawn move that becomes a passer in ending and this passer is uncatchable by the opp king.
MahmoudUthman wrote: *by the way I don't limit the depth of the Q-Search "in case it makes any difference"
QS is inaccurate, don't spend too much time on it. Find a way to exit as early as possible.
To increase accuracy of QS, spend more time to improve your evaluation.