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Subject: Re: Fritz endgame CD

Author: blass uri

Date: 22:03:03 03/24/99

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On March 25, 1999 at 00:19:38, blass uri wrote:


>4)There are errors in the tablebases because the tablebases are based on some
>wrong assumptions:
>
>Here are some wrong assumptions that explain errors for my Fritz5(16 bit):
>
>assumption 1:KRP vs KR cannot be a win for the weaker side.(There is no problem
>of this assumption for KQP vs KQ)
>assumption 2:KQ vs KRP cannot be a win for the weaker side.
>assumption 3:KQX vs KQ when X is not a pawn is a draw unless X is a rook.
>assumption 4:KQR vs KQ cannot be a win for the weaker side.
>
>Uri

I found that the wrong assumptions are not made everywhere.

Here is an example:
8/2q4P/4k3/8/4R2K/8/8/8 b - - 0 1
Fritz5 CD sees that Kf5 is one of the winning moves

If it realy uses assumption 4 then it could evaluated it as draw.
after performing
Kf5 it shows draw evaluation for h8Q,h8N,h8B
It is strange that it shows (-#13) for h8R when black mate in 1 by Qh2#.

The only explanation is that after h8R KxR the cd rom shows mate in 12
The KQ vs KRR is not in the tablebases so Fritz probably searched to see what is
going on and does not know to search correct.

Uri



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