Author: Jeremiah Penery
Date: 18:13:47 10/14/99
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On October 14, 1999 at 20:07:08, Ratko V Tomic wrote: >>That is simply _totally_ wrong. Using micros, we decide what we want to eval, >>we try it, and decide whether the gain from the knowledge is worth the cost in >>search speed/depth. Hsu does the same, except rather than having to choose >>whether to use it or not due to speed, he decides whether to use it or >>not based on whether he wants to design the hardware to handle that. >> >>_EXACTLY_ the same issue, just in a slightly different context. > >Well, same if looked from high up enough and you see generic choices, >prototyping and decision, implementation. That far, they're similar. But a micro >programmers have a more stringent reality check in the five or ten other guys, >as smart and creative or better, competing on the same hardware, same tools. The DB guys had a reality check in Philadelphia, when Kasparov handily disposed of the machine. They obviously still had a lot of work to do in a short time (1 year). The results speak for themselves, IMO. >So, >if they're to be the best, their choices have to be the best. Who is to say which commercial (or not) program is the best today? Is Hiarcs better than Fritz, or Chessmaster, or Tiger, Nimzo, Crafty, Rebel, Junior? Every one of these programs does things differently. Their choices are different, and are what work best _within the framework of that particular engine_. If someone comes up with the "best" forward-pruning algorithm, what's to say it will work equally well in any other engine? Does this make it not the "best" choice anymore? There are _many_ different ways of accomplishing these things, and there almost certainly is no "best" choice for any of them. >DB team has no >real competition, i.e. if they lose to the human champion, they can just say, >well, we did the best with the given means (and no genuine test is there to tell >us whether that was so, it's only their perfectly expected belief), but the >champion was much too strong. For a micro guy, there is always a genuine test, >falsity or less than top quality will fail in the competition on equal footing. > >DB team situation is more like former Soviet industry (not so surprising for >something out of IBM), no genuine competition, no real check, other than >self-imposed one as it suits them (note especially the restrictions on DB or DB >Jr. play against other programs; the general avoidance of genuine tests). We all >know how did Soviet industry & economy eventually fare when faced with genuine >reality check. > >I do think that if the top commercial programs were to get the same speed >hardware as DB, at least couple of them (Hiarcs and Rebel, at least) would be >stronger against the top humans than the DB. Why Hiarcs and Rebel, as opposed to other programs? >Unfortunately, this is at present >untestable belief, but if DB ever gives a match chance to micros, we may be able >to extrapolate some strength relation adjusted for the hardware. It would be nice to see something concrete for once. >> If you really >>believe that others are more creative than the DB team, you are _sadly_ >>mistaken. >> > >Well, if, say, you take Ed vs Hsu, we can say, without knowing the best ideas of >their work, there is a 50% a priori chance Ed is more creative (in his chess >programming work). And the same goes for all the top chess programmers. So, the >odds that Hsu is more creative than, say, the top 5 micro programmers, are 1 in >32, i.e. 3.1%. In other words, the odds that at least some top micro programmers >are more creative than Hsu are about 97%, which supports well my hypothesis >(arrived at another way). Is creativity more important than potential (I'm not sure that's the word I'm looking for. What I'm trying to say is this: Say DB's _potential_ (assuming it was done as well as possibly could've been done) is 1000x of any micro program. Even if they only achieve 1/100 of their potential, they are still 10x better than any micro.) ? The DB guys were certainly creative, as can be seen by their results. I was reading some of the commentary and analysis on DB vs. Kasparov game 6, and it's very relevant here. I'll find and post the relevant sections later. In the way you're speaking, Hsu didn't have to be creative. He could put in all the evaluation he wanted with no worry about speed. There was no "I'll try these 8 selective algorithms, these 3 pruning methods, these several extension ideas, several move ordering schemes, ....etc." in what he did. He could do a deep search with tons of extensions, coupled with a very large evaluation, and using no risky pruning techniques, with _no loss of speed_. >>hmmm.. I have seen 14 ply searches from crafty in the middlegame. I have >>seen DB go incredibly deep, with PVs well over 40 plies long. I doubt that >>will be a serious problem to them. >> >> >I think there was a bit of misunderstanding here. I wasn't saying that programs >won't see something 14 plies deep, but that they _will_ see some apparent 14 ply >gain, which actually is a poisoned gain (of the same kind as the more obvious >gain in the well known opening traps), which was always in that opening, but >human opening theory never warned about them, since humans normally wouldn't see >some long tricky combination to "win" a poisoned pawn. So these are hidden (from >human eye) traps, waiting for the programs to step into. Again, there is some stuff addressing this in the commentary I mentioned. >Well, in match of two identical programs set to search at N and N+1, the >shallower one will win some good percentage of games, maybe 20-30%. So there >must have been good number of positions were _ultimately_ the deeper search >found a substantially worse move (a losing move) than the shallower one. Namely, >it may true that the evaluation will say such positions are rare, but the >ultimate judge is not the (fundamentally inaccurate) evaluation function but the >final outcome. So, there is no question that such positions exist and their >number is not at all vanishingly small. Therefore there may be a general >strategy (including openings) which could guide present-day alpha-beta searchers >into a sample of games biased in favor of such positions. Our present-day chess >trategy is simply not geared toward this objective, and programs are appearing >stronger than they actually will turn out to be. I don't think this is because the deeper search really returns something worse. It can, occasionally, do this, but only because of mis-evaluation. Much of the time, this happens in positions that even a shallow searcher could win. Positions where a 5 ply search and an 8 ply search would return the same result, for example. If the position is better, less plies of search will often be sufficient. Jeremiah
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