Researching if LMR-affected search improves Alpha?

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JVMerlino
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Researching if LMR-affected search improves Alpha?

Post by JVMerlino » Fri Jan 22, 2010 8:58 pm

I can't remember where I saw this, but in Myrddin I have coded the search such that, if a move had LMR reductions applied to it and the search then improves Alpha, that the move should then be researched at the unreduced depth.

Does anybody else do this?

Many thanks in advance,
jm

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Roman Hartmann
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Re: Researching if LMR-affected search improves Alpha?

Post by Roman Hartmann » Fri Jan 22, 2010 9:11 pm

Yes, I'm doing that too. I took the LMR-sheme from Tords website btw (maybe you saw it there too) and it works just nicely and even though I tried to modify LMR several times the research with unreduced depth after improving alpha seems to work best for me.

Roman

zamar
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Re: Researching if LMR-affected search improves Alpha?

Post by zamar » Fri Jan 22, 2010 9:13 pm

Stockfish does that.
Joona Kiiski

Michael Sherwin
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Re: Researching if LMR-affected search improves Alpha?

Post by Michael Sherwin » Fri Jan 22, 2010 9:51 pm

RomiChess is that way.
Regards,
Mike

bob
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Re: Researching if LMR-affected search improves Alpha?

Post by bob » Fri Jan 22, 2010 10:40 pm

JVMerlino wrote:I can't remember where I saw this, but in Myrddin I have coded the search such that, if a move had LMR reductions applied to it and the search then improves Alpha, that the move should then be researched at the unreduced depth.

Does anybody else do this?

Many thanks in advance,
jm
So far as I know, _everybody_ does this. :)

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JVMerlino
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Re: Researching if LMR-affected search improves Alpha?

Post by JVMerlino » Fri Jan 22, 2010 10:42 pm

Well, there it is then. :)

Thanks to everybody who replied!

jm

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