Move ordering - what's best?

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Henk
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Joined: Mon May 27, 2013 10:31 am

Re: Move ordering - what's best?

Post by Henk »

I remember first step to becoming a good tactical player is examining all captures.
So only near the leaves you can be sure bad captures are really bad captures for there is no depth left to examine them.

If you put bad captures at the end of the move list they get reduced too much by LMR. So it may miss good sacrifices.
Or maybe LMR should not reduce any captures?

Also a bad capture might create a passed pawn so it may be difficult to detect bad captures.
Joost Buijs
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Joined: Thu Jul 16, 2009 10:47 am
Location: Almere, The Netherlands

Re: Move ordering - what's best?

Post by Joost Buijs »

Henk wrote: Thu Feb 21, 2019 12:28 pm I remember first step to becoming a good tactical player is examining all captures.
So only near the leaves you can be sure bad captures are really bad captures for there is no depth left to examine them.

If you put bad captures at the end of the move list they get reduced too much by LMR. So it may miss good sacrifices.
Or maybe LMR should not reduce any captures?

Also a bad capture might create a passed pawn so it may be difficult to detect bad captures.
I exclude all tactical moves (captures, promotions, checking moves, evasions and some pawn pushes) from LMR, maybe this is far from optimal, I don't know. There are so many variables to consider, if you all want to check them out by playing engine-engine matches you have to make a full time job of it. In the past I could sit down working for several days in a row on the engine, but that time is long gone.
konsolas
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Joined: Sun Jun 12, 2016 5:44 pm
Location: London
Full name: Vincent

Re: Move ordering - what's best?

Post by konsolas »

I use:
  • Hash
    Good captures (SEE)
    Killers (primary, secondary, and primary from ply - 2)
    Bad captures (SEE)
    Quiets, sorted by history heuristic
I saw a small elo gain after moving bad captures before the quiets, possibly because SEE is often tactically imperfect.
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xr_a_y
Posts: 1871
Joined: Sat Nov 25, 2017 2:28 pm
Location: France

Re: Move ordering - what's best?

Post by xr_a_y »

I saw a small elo gain after moving bad captures before the quiets, possibly because SEE is often tactically imperfect.
How small ?