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Subject: Re: What's the Secret to Shredder 7.04 Success?

Author: Jim Bond

Date: 18:58:19 05/03/03

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On May 03, 2003 at 20:58:31, Tom Kerrigan wrote:

>On May 03, 2003 at 16:50:31, Jim Bond wrote:
>
>>On May 03, 2003 at 15:59:17, Uri Blass wrote:
>>
>>>On May 03, 2003 at 15:45:14, Jim Bond wrote:
>>>
>>>>On May 03, 2003 at 15:10:50, Uri Blass wrote:
>>>>
>>>>>On May 03, 2003 at 14:37:48, Jim Bond wrote:
>>>>>
>>>>>>On May 03, 2003 at 14:07:59, Uri Blass wrote:
>>>>>>
>>>>>>>On May 03, 2003 at 13:44:27, Jim Bond wrote:
>>>>>>>
>>>>>>>>On May 03, 2003 at 10:32:08, George Wilson wrote:
>>>>>>>>
>>>>>>>>>Hi
>>>>>>>>>
>>>>>>>>>  After playing Shredder 7.04 against Several Strong programs on two separate
>>>>>>>>>computers I am very "Impressed" . I wonder though what distinguishes this
>>>>>>>>>program from the other top programs, what gives it the edge in playing strength?
>>>>>>>>> I think it is shredders fantastic endgame prowness. All six of the games it won
>>>>>>>>>against century 4 was in the endgame, however rebel seemed to play even with it
>>>>>>>>>tactically in all the middlegames
>>>>>>>>
>>>>>>>>This could be partly due Shredder's ability to probe ending game table base.  I
>>>>>>>>tend to find that, in its analysis window, the tb numbers are much bigger than
>>>>>>>>other engines.
>>>>>>>
>>>>>>>I disagree
>>>>>>>Bigger is not better.
>>>>>>>
>>>>>>>I did not check your theory but if shredder probes ending tablebases more than
>>>>>>>other programs then it suggests that shredder has not knowledge that it can
>>>>>>>trust without tablebases.
>>>>>>>
>>>>>>>A program with knowledge is not going to probe tablebases in a lot of tablebases
>>>>>>>positions because calculating the winner by knowledge is faster.
>>>>>>>
>>>>>>>Uri
>>>>>>
>>>>>>Calculating the winner by knowledge may be faster but is it more accurate than
>>>>>>tablebase?  I am afraid not.  The table base is a superset of conventional
>>>>>>theory or knowledge.  It is an oracle.  Shredder might be going for accuracy as
>>>>>>oppose to speed.
>>>>>>
>>>>>>Jim
>>>>>
>>>>>It is not less accurate if you do it only in the right part of the cases.
>>>>>The right part can be bigger when the program has more knolwedge.
>>>>>
>>>>>Uri
>>>>
>>>>Not less accurate?  So are you claiming you or someone can program chess
>>>>knowledge equally or more accurate than the complete 5-men tablebase?  I believe
>>>>the fact is no body can otherwise there wouldn't be tablebase at all.  People
>>>>wouldn't have developed it in the first place.  Can anyone cover all the "right
>>>>parts" as quoted from you?  Have anyone been able to?  I am afraid not.
>>>>
>>>>Jim
>>>
>>>I do not use tablebases in movei but there are cases that can be evaluated
>>>correctly without tablebases
>>>
>>>I can give you examples:
>>>
>>>KQ vs K is always a win if the position is not stalemate and findin if the
>>>position is stalemate is faster than calling tablebases.
>>>
>>>KBP vs K is a draw when the bishop is blind and the king is close enough to the
>>>corner.
>>>
>>>KPP vs KP is a win for the side with the pp if this side is to move and has
>>>unstoppable pawn  and the distance of the opponent's pawn to be a queen is
>>>bigger by at least 2.
>>>
>>>It is possible to define a lot of rules that will be 100% correct and will cover
>>>part of the cases.
>>>
>>>The main part when they can help is in positions when one side has 3 pieces
>>>because these cases can be detected as wins in most of the cases with no errors
>>>in the cases that they are detected as wins.
>>>
>>>Uri
>>
>>Thanks for sharing the rules.  However I wonder if anyone can program a rule
>>that can accurately solve this Queens-pawn mate in 63 ending position (126 half
>>moves).  The program would have to tell me 1, -1 or 1/2 accurately without TB.
>>
>>8/4q2K/1k5p/7Q/6P1/8/8/8 w - - 0 81
>>
>>My point is that in simpler cases, 100% accuracy it is possible, but in more
>>complicate cases, without TB, it is not humanly programmable or computer
>>searchable.  I am only guessing Shredder might be taking advantage of TB to a
>>greater degree than other programs given TB is the "truth".
>>
>>Jim
>
>What's your problem?
>
>Uri never said that rules are accurate in all cases or that tablebases are
>unnecessary and should never be probed.
>
>Of COURSE you can find cases where rules will not apply. That's when you do a
>lookup. The fact that you can find these cases completely misses the point.
>
>-Tom

You are welcome to adding your opinions.  I guess you want to clarified what Uri
has been trying to say - more TB probing is bad.  Do you agree?

Jim





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