Author: Sune Fischer
Date: 12:25:46 07/27/04
Go up one level in this thread
On July 27, 2004 at 15:03:30, Robert Hyatt wrote: >On July 27, 2004 at 14:43:06, Sune Fischer wrote: > >>On July 27, 2004 at 13:33:40, Robert Hyatt wrote: >> >>>On July 27, 2004 at 09:42:46, Sune Fischer wrote: >>> >>>>On July 27, 2004 at 09:33:13, Anthony Cozzie wrote: >>>> >>>>>On July 27, 2004 at 03:18:50, Sune Fischer wrote: >>>>> >>>>>>On July 25, 2004 at 22:01:31, Robert Hyatt wrote: >>>>>> >>>>>>>Bad idea. Start the next iteration even if you don't think you will have time >>>>>>>to finish it. You might fail low. Wouldn't that be nice to know? :) >>>>>> >>>>>>This may or may not be a good idea. >>>>>> >>>>>>I think if it is a good idea, then you should always try and search the next >>>>>>iteration for a short time to see if you get a quick fail-low. >>>>>> >>>>>>On the other hand, if it is a bad idea it is better to save the time that will >>>>>>probably be wasted anyway. >>>>>> >>>>>>From what I can tell you propose to do a mixture, i.e. to use extra time if the >>>>>>time manager tells you to? >>>>>> >>>>>>I really doubt this is the best way, because it will be extremely random when >>>>>>you get to begin the next ply. >>>>>> >>>>>>-S. >>>>> >>>>>It seems you have 3 options here: >>>>> >>>>>Optimism: Hope that a move you haven't searched yet will fail high; terminate >>>>>after searching all moves. >>>>> >>>>>Pessimism: Make sure that the move you want to play won't fail low: terminate >>>>>after searching the first move. >>>>> >>>>>Don't Care: Just exit whenever time runs out ;) >>>> >>>>I think you have more choices, e.g. search the next ply, when time is about to >>>>run out, with a null window around the fail-low bound. >>> >>>I don't think any of that is reasonable. I have seen searches where the first >>>move takes 1 second to resolve a true score. I have seen searches where the >>>first move will talk almost forever to resolve the score. KISS is a good idea >>>here, IMHO. >> >>...which is why you shouldn't try and resolve the score. :) > >How is that KISS? IE I +normally+ try to resolve the score, so why change what >is the normal case??? For a special case that is not particulary significant. Because you could normally save 20% of your time?! Only way to know is to try it, I can only say it works for me :) > >> >>>> >>>>Just to assert as quickly as possible that it doesn't fail horribly low. >>>> >>>>Little sense in trying to resolve an exact score for the next ply if you only >>>>15% time left. >>> >>> >>>Often that is more than enough time to resolve the score. >> >>I think 15% is rarely enough time. > > >100 seconds per move. 15% is 15 seconds. For the first N iterations that is >more than enough time. How to accurately predict when you are starting the >_last_ iteration? Well, e.g. compare time remaining with the time spent on the last iteration, use a bit of logic and you might eventually get there... :) >> >>If the whole last ply took 70% and the first move on the last ply took 60%, then >>you can probably expect to use about twice that, i.e. 120% time, to resolve the >>score on the first move. >> >>That's pretty hopeless unless something dramatic happens. >> >>-S. > >Try fine 70 for a quick counter-example... Howso? -S.
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