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Subject: Re: EGTB question

Author: Mike Hood

Date: 09:38:55 09/28/01

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Thanks for the reply, Eugene. I'm willing to accept I may be wrong, but how do
you explain the discrepancies I named?

Mike

On September 28, 2001 at 11:11:33, Eugene Nalimov wrote:

>There is no bug in TBSTAT, and statistics is correct.
>
>Eugene
>
>On September 28, 2001 at 08:27:37, Mike Hood wrote:
>
>>On September 19, 2001 at 04:23:39, Les Fernandez wrote:
>>
>>>Has anyone tabulated the total win-lose-draw-broken positions for first the 3
>>>then 4 and then the 5 piece sets?  I know that the information is available on
>>>Bobs ftp site but hoping that someone has already done it for both WTM and BTM
>>>so I dont have to do them one by one.
>>>
>>>ie:
>>>
>>>EGTB     WINS     LOSE     DRAW     BROKEN
>>>
>>> 3
>>> 4
>>> 5
>>
>>This is theoretically possible, but not very sensible at the moment. Most of the
>>TBS files on Robert Hyatt's ftp server are defective, probably due to a bug in
>>TBSTAT.
>>
>>For instance:
>>
>>krrk.tbs -- On black's move there are 1032 positions that lose in 16, but on
>>white's move the longest mate is Mate in 7.
>>
>>kqrkr.tbs -- On black's move there are 60 moves that are Mate in 5, but there
>>are ZERO moves that are Mate in 4.
>>
>>kbpk.tbs -- On white's move there is 1 position that is Mate in 31, but there
>>are ZERO moves that are Mate in 30.
>>
>>In most of the TBS files the number of broken positions is not listed.
>>
>>Over 50% of the TBS files are obviously defective, and I can't vouch for the
>>validity of the others. And, to ask a naive question, shouldn't the number of
>>Mates/Losses/Draws in a pawnless tablebase always be divisible by 4?
>>
>>I've reported the bug to Eugene by email a few weeks ago, but it hasn't been
>>fixed yet.
>>
>>Mike
>>
>>**** Dansez de la apusul pana la rasaritul soarelui ****



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