Author: Robert Hyatt
Date: 18:35:52 03/16/04
Go up one level in this thread
On March 16, 2004 at 16:31:00, Gerd Isenberg 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??? >> >>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... > > >Ok, i may find three positions too where some additional random move ordering >results in similar smaller trees ;-) I didn't "pick" three positions. Those are just the last 3 kopec positions as they were easy to grab. I'll be happy to test any group you want to choose however. :) When I tuned history a long time back, I used about 100 positions to test. > >I believe in HH too, still use byte arrays with some degree of saturation. >I count overflows for each color if 255. >I age them by div two if some amount of overflows occurs. >I use higher increment for mate threads if < 200. >I use countermove or butterfly heuristic too and of course killers. >With depth left > 3 i use more sophisticated move sorting. > >In my next generation approach i will try move-index in a range of about >0...4000 (quite moves per side) to distinguish not only between coordinates but >pieces too. Curious about the infuence on HH with those indices. > ><snip>
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.