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Subject: Re: Lies.. Damn Lies & Statistics!

Author: Dann Corbit

Date: 18:21:34 01/12/05

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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...

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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