Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: What is the Success Rate of Killer/History Moves?

Author: Roberto Waldteufel

Date: 23:49:29 05/31/00

Go up one level in this thread


On May 31, 2000 at 23:55:25, Robert Hyatt wrote:

>On May 31, 2000 at 16:29:48, Roberto Waldteufel wrote:

>>My currant move order is:-
>>
>>1)Null Move
>>
>>2)Hash move
>>
>>3)My heuristic move (if legal and different from (2))
>>
>
>The next three are 'broken'.  They should all be folded together.  IE
>ep captures could be the first one chosen.  And you should certainly search
>e8=Q before trying Bxh6, assuming e8=q doesn't lose material.
>
>Also castling moves are just "moves".  these could be suggested by the killer
>heuristic, by the history heuristic, but I wouldn't try them in a fixed place
>just because they are castling moves.
>
>
>
>
>>4)Captures in MVV/LVA order
>>
>>5)Non-capturing pawn promotions
>>
>>6)En Passant captures
>>
>>7)Castling
>>
>>8)Non-capture Moves with all pieces except the king and pawns
>>
>>9)Non-capture king moves
>>
>>10)Non-capture/Non-Promoting Pawn moves
>>

[snip]

My motive for putting castling first among non-capture/non-promotion moves was
that castling, if legal, is usually a good move. I could generate all the
captures/promotions and sort them before searching, but the program has no way
of telling which are good and which are bad before it has searched them. I
believe you use a static swap evaluator to order your captures - I would be
interested to try a similar idea - but I am not sure how you evaluate the swaps
without incurring a lot of overhead? My present arrangement never generates a
move until it is ready to search it. Perhaps this is misguided and some static
analysis would save time by improving the cut-off rate? If I understand
correctly DarkThought uses the same MVV/LVA order for the captures without
generating any moves "in advance" until it gets to the non-captures. How does
your static swap evaluator work?

Best wishes,

Roberto



This page took 0 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.