Author: Christophe Theron
Date: 10:18:04 04/15/04
Go up one level in this thread
On April 15, 2004 at 01:05:38, martin fierz wrote:
>On April 14, 2004 at 19:29:44, Christophe Theron wrote:
>
>>On April 14, 2004 at 12:32:56, Robert Hyatt wrote:
>>
>>>On April 14, 2004 at 10:21:55, martin fierz wrote:
>>>
>>>>On April 13, 2004 at 17:00:24, Matthew Hull wrote:
>>>>
>>>>>On April 13, 2004 at 14:21:07, Christophe Theron wrote:
>>>>>
>>>>>>On April 13, 2004 at 01:29:02, Russell Reagan wrote:
>>>>>>
>>>>>>>On April 12, 2004 at 23:07:46, Christophe Theron wrote:
>>>>>>>
>>>>>>>>Further, wouldn't you just *hate* if I took the fun out of chess programming by
>>>>>>>>telling you everything? :)
>>>>>>>
>>>>>>>My gut feeling is that we would probably be disappointed for the most part. I
>>>>>>>bet a lot of us think all of you commercial authors are harboring lots of
>>>>>>>magical secrets that can turn an average program into a beast. Something similar
>>>>>>>to the improvements you get by going from minimax to alphabeta, or by adding
>>>>>>>null-move to an average program, and things like that. Those are very
>>>>>>>significant improvements.
>>>>>>>
>>>>>>>I have received the impression from you and other sources like Ed's webpage that
>>>>>>>this is not the case. There are some clever things on Ed's webpage, but for the
>>>>>>>most part, it is good ideas based on common sense, and then taking the time and
>>>>>>>effort to hammer out every last detail to make an idea work, followed by an
>>>>>>>efficient implementation.
>>>>>>>
>>>>>>>To illistrate the difference between what I think a lot of people would expect
>>>>>>>to hear from you if you divulged all of your secrets and what I think we would
>>>>>>>really get, consider null-move. Null-move is something that you can add to a
>>>>>>>program that uses no forward pruning, and once you spend a small amount of time
>>>>>>>getting it to work right, the program suddenly plays like it's on steroids
>>>>>>>(relatively speaking). However, if we took an average program and added in a few
>>>>>>>ideas from Ed's webpage, I wouldn't expect nearly as big of an improvement. I
>>>>>>>think you guys just take a lot of ideas and get small improvements here and
>>>>>>>there, and at the end of the decade, it amounts to a big improvement. 10%
>>>>>>>reduction in tree size here, 20% there, it adds up.
>>>>>>>
>>>>>>>Am I right? If we are expecting to see magical earth shattering secrets, would
>>>>>>>we be disappointed?
>>>>>>
>>>>>>
>>>>>>
>>>>>>I don't think you would be disappointed.
>>>>>>
>>>>>>But you are right in assuming that you would not see a dramatic improvement such
>>>>>>as the one you get from alpha-beta vs minimax.
>>>>>>
>>>>>>You know, one has to wonder where the difference in elo strength between Crafty
>>>>>>and the top commercial comes from.
>>>>>
>>>>>
>>>>>Compare this with your mileage at home. Many of the plus performance scores are
>>>>>against accounts running commercial programs.
>>>>
>>>>
>>>>this is irrelevant to the discussion - crafty on ICC is running on 4 processors.
>>>>big hardware difference...
>>>
>>>Nope. Dual xeon 2.8 with hyperthreading on. There are faster duals on ICC
>>>running the "deep programs."
>>>
>>>
>>>>
>>>>it's just what christophe was writing about: crafty is competitive because it
>>>>can use multiple processors (x4 = ~100 rating points). on single processor PCs,
>>>>it is not competitive with top commercials.
>>>>
>>>>the reason is that the commercial programmers write a program for the user who
>>>>buys it - and this user has 1 processor, with *very* few exceptions. if bob had
>>>>spent his time on eval, he would be quite competitive too on single processors
>>>>IMO, but that is not what he chose to do.
>>>>
>>>>i'm speculating here, but probably it's easier for him to focus on
>>>>multiprocessing than on knowledge&search for "political" reasons. when you're
>>>>paid by the university to do research, they want you to do something that the
>>>>people in charge perceive as "useful". tweaking an evaluation function would
>>>>probably sound less useful than accomplishing the parallelization of a complex
>>>>program. parallelization is also interesting for computer science students,
>>>>because the future will bring more multiprocessing systems - also because of
>>>>things like hyperthreading on one processor.
>>>>
>>>>cheers
>>>> martin
>>>
>>>Actually UAB doesn't care. I focus on parallel search because that is actually
>>>what interests _me_. It's an interesting problem. In 5 years _everybody_ will
>>>have a dual as a single chip will have 2-4 processors on it...
>>
>>
>>
>>That's what somebody insisted on telling me in Paderborn, 1999.
>>
>>Maybe it was Martin, actually I don't remember.
>
>do you mean me? i was never in paderborn :-)
>
>cheers
> martin
So it was not you. Sorry, and sorry for the guy who was here. There were so many
new faces for me to discover at Paderborn, I think I'm mixing everything up...
Christophe
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