Move ordering - what's best?

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Henk
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Re: Move ordering - what's best?

Post by Henk » Thu Feb 21, 2019 11:28 am

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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Re: Move ordering - what's best?

Post by Joost Buijs » Thu Feb 21, 2019 3:56 pm

Henk wrote:
Thu Feb 21, 2019 11:28 am
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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Re: Move ordering - what's best?

Post by konsolas » Thu Feb 21, 2019 9:38 pm

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
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Location: France

Re: Move ordering - what's best?

Post by xr_a_y » Fri Feb 22, 2019 12:22 pm

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

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