Author: chandler yergin
Date: 20:59:36 01/13/05
Go up one level in this thread
On January 13, 2005 at 15:52:19, Duncan Roberts wrote: >On January 13, 2005 at 12:50:52, Robert Hyatt wrote: > >>On January 12, 2005 at 21:47:05, Les Fernandez wrote: >> >>>On January 12, 2005 at 21:21:34, Dann Corbit wrote: >>> >>>>On January 12, 2005 at 21:18:22, chandler yergin wrote: >>>> >>>>>On January 12, 2005 at 21:13:08, Dann Corbit wrote: >>>>> >>>>>>On January 12, 2005 at 21:09:16, chandler yergin wrote: >>>>>> >>>>>>>On January 12, 2005 at 21:02:01, Dann Corbit wrote: >>>>>>> >>>>>>>>On January 12, 2005 at 20:57:40, chandler yergin wrote: >>>>>>>> >>>>>>>>>On January 12, 2005 at 20:33:25, Dann Corbit wrote: >>>>>>>>> >>>>>>>>>>On January 12, 2005 at 20:25:24, Uri Blass wrote: >>>>>>>>>> >>>>>>>>>>>On January 12, 2005 at 19:56:25, Dann Corbit wrote: >>>>>>>>>>> >>>>>>>>>>>>On January 12, 2005 at 19:37:29, Steve Maughan wrote: >>>>>>>>>>>> >>>>>>>>>>>>>Dann, >>>>>>>>>>>>> >>>>>>>>>>>>>>Things that seem impossible quickly become possible. >>>>>>>>>>>>> >>>>>>>>>>>>>I recon about 300 years before a computer will solve chess. This assumes >>>>>>>>>>>>> >>>>>>>>>>>>>1) 10^120 possible positions >>>>>>>>>>>> >>>>>>>>>>>>This is far, far too large. Chess positions have been encoded in 162 bits, >>>>>>>>>>>>which puts an absolute upper limit at 10^58 (and it is probably much less than >>>>>>>>>>>>that). >>>>>>>>>>>> >>>>>>>>>>>>>2) Alpha-beta cutting this down to 10^60 sensible positions >>>>>>>>>>>> >>>>>>>>>>>>The incorrect first assumption renders this and all following assumtions as >>>>>>>>>>>>moot. >>>>>>>>>>> >>>>>>>>>>>The second assumption is also not correct. >>>>>>>>>>> >>>>>>>>>>>By the same logic alphabeta can cut less than 2^30 positions in KRB vs KR to >>>>>>>>>>>2^15 positions but it does not happen and solving some KRB vs KR position with >>>>>>>>>>>no KRB vs KR tablebases is not something that you need 2^15 nodes for it. >>>>>>>>>> >>>>>>>>>>No. The second assumption would be true if the first was true. This was >>>>>>>>>>formally PROVEN by Donald Knuth. In a perfectly ordered alpha-beta solution >>>>>>>>>>tree, the number of nodes is proportional to the square root of the nodes in the >>>>>>>>>>full tree. >>>>>>>>>> >>>>>>>>>>If there were 10^120 in the full tree, then about 10^60 would be in the solution >>>>>>>>>>tree. >>>>>>>>>> >>>>>>>>>>It can be less than that. >>>>>>>>> >>>>>>>>>It "Can't be LESS than that! >>>>>>>>> >>>>>>>>> But it cannot be more. >>>>>>>>> >>>>>>>>> >>>>>>>>>It Certainly CAN! >>>>>>>>> >>>>>>>>>In any TREE.. the TREE ONLY represents "What HAS Been PLayed." >>>>>>>>>REFUTE THAT! >>>>>>>> >>>>>>>>You do not have to solve every game. Only every position. Look at the two >>>>>>>>chess games that I posted. The end position for both was identical. In fact, >>>>>>>>despite the many moves, there are only a very few positions that are distinct. >>>>>>>>For each of those positions, if you know the best move, you do not care how you >>>>>>>>got there. >>>>>>>> >>>>>>> >>>>>>>How do you now the "Best Move" until you have calculated them ALL? >>>>>> >>>>>>The miracle of alpha beta is that it allows you to prune away huge chunks of the >>>>>>tree and get EXACTLY the SAME answer you would get if you examined every single >>>>>>leaf. >>>>>> >>>>>>>Hmmm? >>>>>> >>>>>>Read a paper on alpha-beta and you will find the answer. >>>>> >>>>>Still doesn't come CLOSE to 10^ 120th Power for Solving ANYTHING! >>>>>Also.. there are positions for "Underpromotion" which you don't take into >>>>>account. >>>> >>>>Underpromotion is also completely irrelevant. Each of the possible outcomes of >>>>promotion is simply a new position. Those positions have already been counted >>>>in the set of 10^43 distinct positions. So you see, underpromotion does not >>>>even complicate things at all. >>>> >>>>>That's WHY 7 man EGTB'S will NOT jump the ELO Rating... >>> >>>#1 Chandler just because we do not see a measurable advantage that 6 piece >>>egtb's offer a computer doesnt mean that a larger,ie 10 piece egtb, wouldnt be >>>measurable. Think about it. With only 6 pieces on the board most GM's I >>>suspect would know how to handle that even though some of the 6 piece egtb's can >>>be very tough even for them. Now if that GM was to try and develope a workable >>>approach to survivng an endgame for which we have perfect information for 10 >>>pieces I doubt in most cases he could survive (IMHO). I suspect the benefits of >>>egtb's will become more obvious as we develope large sets. >>> >>>#2 In one of the other threads of yours you mentioned the incredible magnitude >>>of chess positions and that there was 0% chance of solving chess. Well in >>>support of Dann's statement where he corrected your figure of 10*120 let me just >>>say that although perfectly ordered alpha-beta solution will reduce this number >>>I can probably also reduce that number quite a bit further when we talk about >>>unique positions vs positions. Although the task "seems" unattainable you just >>>probably have not looked at all kinds of methods that may offer ways of trimming >>>down that one number that you are baseing all your thoughts on. Keep an open >>>mind, we see this stuff happen every day in technology. >>> >>>Les >>> >> >> >>This is irrefutable: Each successive generation of tables provides a _higher_ >>strength improvement than the previous generation, until we get the 32 piece >>tables done at which point perfect chess will be played. We won't reach there >>for a long time, if ever (never is such a long way away I try to not use it) but >>from personal experience, having started off with just 3-4 piece files, then >>adding all the 5's, I can assure you that the 5 piece files added much more to >>my program than the 3-4 piece files did. And the 6's have added even more even >>though all are not done. I can't say it is an exponential growth with so few >>data points, but I can say without fear of being proven wrong later that it is >>just as clearly more than a linear growth in playing strength. > > >could you comment about the table base searches slow the software down a lot. > >duncan > They DON'T Slow it down at ALL! It's instantaneous! >> >> >> >> >>>>>>>>>>tree >>>> >>>>That has more to do with disk access time. But I expect that judicious use of >>>>the data will increase Elo ratings. >>>> >>>>>They, can't even be solved yet.. and NOT in your lifetime either.. will they.. >>>>>or for future generations to come. >>>>>STOP! The NONSENSE!
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