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

Author: Jim Bond

Date: 20:54:19 05/03/03

Go up one level in this thread


On May 03, 2003 at 23:14:26, Tom Kerrigan wrote:

>On May 03, 2003 at 21:58:19, Jim Bond wrote:
>
>>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
>
>Uri has been saying nothing of the sort--he's saying that a probe is not
>necessarily good, i.e., when you can get a perfectly accurate rule-based answer
>much faster.
>
>-Tom

You are saying "a probe is not necessarily good" but I believe at least it is
accurate.  I think you meant to say more probes are not necessary more efficient
which is acceptable but you can not deny the a fact that Shredder does more
probes and it is the top program.  I am not say the correlation is 100% but the
correlation is there.

Jim




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