Author: Robert Hyatt
Date: 18:32:53 03/16/04
Go up one level in this thread
On March 16, 2004 at 17:45:49, Vincent Diepeveen wrote: >On March 16, 2004 at 14:48:14, Robert Hyatt wrote: > >>On March 16, 2004 at 13:52:21, Mridul Muralidharan wrote: >> >>>On March 16, 2004 at 13:06:34, Robert Hyatt wrote: >>> >>>>On March 16, 2004 at 12:41:55, Sune Fischer wrote: >>>> >>>>>On March 16, 2004 at 12:30:42, Robert Hyatt wrote: >>>>> >>>>>>On March 16, 2004 at 12:04:22, Sune Fischer wrote: >>>>>> >>>>>>>On March 16, 2004 at 11:25:55, Vincent Diepeveen wrote: >>>>>>> >>>>>>>>On March 16, 2004 at 11:19:17, Renze Steenhuisen wrote: >>>>>>>> >>>>>>>>I principally agree with GCP here. I do not understand how in certain software >>>>>>>>HH can work. Must be a bug in their move ordering IMHO. >>>>>>> >>>>>>>If you can't make them work, why do you reply to his post? >>>>>>> >>>>>>>-S. >>>>>> >>>>>> >>>>>>Ignorance. Unabashed ignorance... >>>>>> >>>>>>What else? >>>>>> >>>>>>HH works just fine. Of course if Vincent can't get them to work, then it is >>>>>>impossible that they will work for anybody. "proof" enough?? >>>>> >>>>>Yes, and this time the poster even gets to contact him personally for more >>>>>information on how NOT to make them work! >>>>> >>>>>I admit I can see his point, precious secrets _like that_ are not to be posted >>>>>in a public forum :) >>>>> >>>>>-S. >>>> >>>> >>>>none of his "precious secrets" should be posted... >>>> >>>>:) >>> >>>Just try this - after the end of a 3 min search from a fairly complicated middle >>>game position (like for example - Nxh6 nolot position) , print out the history >>>values. >>> >>>You will see the junk that is contained in the table. >> >>Do you understand what this "junk" means??? > >You obviously do not. It works for me, and for others, so what part don't I understand? Your hand-waving?? I _never_ understand that... > >you collect about something very general data. that's just *too* general data. Obviously not since it _works_... > >>I don't see how it can be called "junk". The data simply reflects how useful >>each move was in the search done. > >>> >>>If you seriously expect much of information to be obtained from this for move >>>ordering - I dont know what to say. >> >>I feel the same, except in an inverse way. >> >>History works for me. Turn it off and the tree gets bigger. A couple of >>samples: >> >> nodes w history nodes wo history >>pos1 38,151,984 42,728,175 >>pos2 167,685,660 184,874,107 >>pos3 81,663,363 124,704,814 >> >>Now if you believe those three randomly chosen positions are worse because of >>"random junk" feel free. The tree size is _remarkably+ smaller on pos 3, and >>significantly smaller on the other two... >> >> >> >> >>> >>>I like some other mentioned here though - clear it x number of ply or y number >>>of seconds - helps to reduce the randomness. >> >>Why would I want to do that? This data is useful all over the tree. This is >>the very idea behind it. Killers are local. History is global. Use both. >> >> >> >>>Also Ed's idea is also somewhat better. >>> >>>I have not tried these , so cant comment - but helps in localising the effects >>>to a smaller subtree where the tables could be potentially more relevent. >>> >>>But essentially , history tables in the general sense will detreriorate into >>>random move ordering quiet soon for higher depth when number of nodes increases. >> >>Then explain how my "random move ordering" is way more efficient. You are not >>understanding what goes on in the history heuristic within the tree... >> >> >>> >>>Is that one of the reasons why you sort and try history scores for only first n >>>(i think 4) number of history moves in crafty ? >> >>Nope. It is for efficiency. at ALL nodes ordering is irrelevant. If, after >>the hash move, good captures, two killers, I can't get a cutoff on one of the >>first four history moves, I give up as I probably won't get a cutoff at all. >> >> >> >> >>> >>>Maybe this could be an optimisation reason also - i dont know. >> >>It isn't anything but performance based... >> >> >>> >>>But if there is a possibility of hitting a better move earlier on using history >>>tables , then shouldn't crafty not be trying it for all the moves ? - the gain >>>could be potentially exponential in case of earlier cutoff ! >> >>I _do_ try it _everywhere_.... >> >> >>> >>>Mridul
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