Author: Ed Schröder
Date: 02:44:36 07/22/00
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On July 21, 2000 at 22:27:45, Robert Hyatt wrote: >On July 21, 2000 at 19:16:41, Ed Schröder wrote: > >>On July 21, 2000 at 15:29:26, Robert Hyatt wrote: >> >>If you don't mind I only answer those points not earlier discussed >>(enough) to avoid ending up in endless circles. >> >> >>>>2) DB is no brute force program (as you always have claimed). Quote >>>>from the IBM site: >>>> >>>> "Instead of attempting to conduct an exhaustive "brute force" >>>> search into every possible position, Deep Blue selectively >>>> chooses distinct paths to follow, eliminating irrelevant searches >>>> in the process." >>>> >>>>I always said this after I had seen the log-files. It beats me how you >>>>always have claimed the opposite on such a crucial matter presenting >>>>yourself as the spokesman of Hsu even saying things on behalf of Hsu >>>>and now being wrong on this crucial matter? >>> >>>Sorry, but you are wrong and are interpreting that wrong. DB uses _no_ >>>forward pruning of any kind, this _direct_ from the DB team. The above is >>>referring to their search _extensions_ that probe many lines way more deeply >>>than others. If you want to call extensions a form of selective search, that >>>is ok. It doesn't meet the definition used in AI literature of course, where >>>it means taking a list of moves and discarding some without searching them at >>>all. >> >>The quoted text describes DB as a selective program, no brute force. I >>don't see how you can explain it otherwise. The text is crystal clear. >> >> > >Why don't you simplyh ask Hsu, or are you afraid you will get an answer >you don't want? DB was _always_ brute force. Every document written about >DB said this. The paragraph you are quoting is talking about "selective >search extensions" which was one of the real innovations from the Deep Thought >development (singular extensions, later used by Lang, Kittinger, Moreland, >Hyatt, who knows who else). I disagree. Extensions are always selective. Some moves are extended some don't and that makes that extensions is a selective process by nature. So the text (about brute force) can't be related to the previous sentence (about extensions). They made 2 statements (not one). >You _know_ they were basically in the same mold as the rest of us. This has >_never_ been in doubt. > >If you do doubt it, just ask the horse's mouth, since you don't want to believe >me. > > > >> >>>This _was_ deep thought. It was doing about 2M nodes per second in 1995, >>>according to Hsu. >> >>Then Hsu is wrong or the IBM site. >> >>Quote from the IBM site: >> >> "Deep Thought acquires 18 >> additional customized chess >> processors and emerges as >> Deep Thought II. It now is >> running on an IBM/6000 and >> can search six to seven million >> chess positions per second. > > >That was correct. But as I said (after a conversation with Hsu) it _never_ >really ran at that speed. The few times they tried to use all the hardware, >things didn't work out very well (this was mainly used during the Fredkin >stage II matches, where they physically shipped the machine (a single Sun >workstation + the VME cards) to remote locations. > >Hsu has said point blank, the most recent version of DT was searching about >2M nodes per second. I take him at his word, since he built the thing... The only thing that counts here is the contradicting data: 1991: IBM 7 million 1995: Hsu 2 million Now who to believe that's the question. >> >>6 to 7 million NPS. This in the year 1991 so 4 years before the Hong Kong >>event. So according to Hsu and/or IBM in 1995 the machine dropped from 7 to >>2 million NPS?? One might expect the opposite, a faster machine after >>4 years but not a slower one. Something ain't right with these numbers. > > >Simply email Hsu... it was his box. He can tell you what you want to >know... > > >> >> >>>Fine. Again, Hsu is a liar. If that is what you want to think. Here is >>>an excerpt from him that might help: >>> >>>=============================================================================== >>>Web-based DB Jr uses a single card, a random opening book (including >>>fairly bad lines) and one second per move (a quarter of which is used >>>in downloading the evaluation function, and the search extensions are >>>more or less off due to the very short time). It probably plays at around >>>2200, which is usually sufficient to play against players in random marketing >>>events. Repetition detection is also turned off (The web-based program >>>is stateless). The playing strength of "DB Jr." spans a quite wide range, >>>depending on the setup. The top level, which we used for analysis and >>>in-house training against Grandmasters, is likely in the top 10 of the >>>world. >>>================================================================================ >> >>I said the contradiction is in the private emails so you can't know. >> >>Ed > > >No, but I believe from the above, which is also private email, there is >absolutely no confusion in what "web DB Jr" was. It is _very_ clear, and >not open to misinterpretation, wouldn't you say?? > >It was thrown together at the request of marketing guys. And "thrown together" >is a pretty accurate description. He says "2200". In another email he said >"2200 might have been optimistic"... Every time it is something else. I stopped believing it. Ed
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