Playing transposition table moves in the Quiescence search

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jdart
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Re: Playing transposition table moves in the Quiescence search

Post by jdart » Sat Jan 19, 2019 2:45 pm

I have looked at my code again after seeing this thread. I try to use the hash move in the q-search if possible, to possibly avoid calling the move generator. I found though that it wasn't quite filtering hash moves that originally were not from the q-search so that they met all the q-search conditions. So far fixing this appears to be a tiny gain but it is within the error bars of my testing, so not clear.

--Jon

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cdani
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Re: Playing transposition table moves in the Quiescence search

Post by cdani » Mon Jan 21, 2019 7:34 pm

D Sceviour wrote:
Fri Jan 18, 2019 1:40 am
Would not quiet moves explode and make the position noisy? Daniel Jose Queralto (Andscacs) suggested a complete QS cutoff at depth of -6. Current tests on my engine demonstrate an elo loss with any QS depth cutoff. The exchange combinations are necessary. There are SEE methods that try to reduce the exchange calculations, but are they really any faster or more effective than a standard quiescent exchange search?
What I do is, from -5 I search only recaptures.

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silentshark
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Re: Playing transposition table moves in the Quiescence search

Post by silentshark » Mon Jan 21, 2019 7:38 pm

Well, I did some quick testing. Not doing tt probes in qsearch was -22 ELO for me. But that was after 600 odd games. Probably need to run more tests, but removing tt probes doesn't seem like a win (for me).

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cdani
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Re: Playing transposition table moves in the Quiescence search

Post by cdani » Mon Jan 21, 2019 7:40 pm

D Sceviour wrote:
Fri Jan 18, 2019 1:40 am
The tt move, if any, should be tried first. As long as it does not lose elo, this seems to be theoretically correct. I never found a non-capture move in the tt table on the horizon. This is because a non-capture tt best move would have a greater depth stored and the hash probe should prune.
Hash probe prune depending on the depth and on the bounds.

I take any hash move in Andscacs, and many times is a quiet move. Nothing bad seems to happen.

flok
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Re: Playing transposition table moves in the Quiescence search

Post by flok » Tue Jan 22, 2019 11:32 am

cdani wrote:
Mon Jan 21, 2019 7:34 pm
D Sceviour wrote:
Fri Jan 18, 2019 1:40 am
Would not quiet moves explode and make the position noisy? Daniel Jose Queralto (Andscacs) suggested a complete QS cutoff at depth of -6. Current tests on my engine demonstrate an elo loss with any QS depth cutoff. The exchange combinations are necessary. There are SEE methods that try to reduce the exchange calculations, but are they really any faster or more effective than a standard quiescent exchange search?
What I do is, from -5 I search only recaptures.
gives me -29 elo, doing only recaptures from -5 (11k games)
www.vanheusden.com: Embla / PuppetMaster / DeepBrutePos / Pos / Feeks

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