Author: Robert Hyatt
Date: 15:34:17 03/30/00
Go up one level in this thread
On March 30, 2000 at 15:47:03, Inmann Werner wrote: >On March 30, 2000 at 15:39:09, Peter Fendrich wrote: > >>On March 30, 2000 at 15:04:09, Inmann Werner wrote: >> >>>On March 30, 2000 at 11:07:16, Robert Hyatt wrote: >>> >>> >>>>Here is mine: >>>> >>>>1. hash table move. >>>>2. captures that don't appear to lose material using a SEE procdedure, >>>>ordered from biggest gain to equal exchanges. >>>>3. 2 killer moves. >>>>4. up to 4 history ordered moves (history heuristic) >>>>5. rest of the moves. >>> >>>question to 5) >>>here is the rest of the non capturing moves and the "loosing capture" moves. >>>Which of them should be searched first? >>> >>>IMHO the non capturing moves. >>> >>>Werner >> >>I don't think you should order them at all... >>When the program reaches this point it will probably not find a fail high for >>the current node and the sorting will only cost performance without giving much >>in return. >>//Peter > >Excuse, but I do not agree. >Why should a good positional move not produce a fail high? >And i do not sort. I only give the moves "values" at generation time. In search, >I only look at the first 9 moves in an ordered way, the rest i pick at random. >My question is: When I produce the "loosing captures" (together with all >captures), I can give them a small positive or a negative value (without cost). > >I give them a negative value, and it works a little better than otherwise. > >Werner The reason is this: If you spend much time sorting, and (as in Crafty) 92% of the fail highs happen on the first move searched, by the time you get thru the captures, the killers, and the history moves, the probability of a fail high is _very_ remote. How much time are you willing to invest to get that occasional quick fail high? Hard to say what the right answer is, there...
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