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Subject: Re: Stalemating swindle

Author: James T. Walker

Date: 08:00:28 11/28/02

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On November 28, 2002 at 03:32:44, Alastair Scott wrote:

>On November 28, 2002 at 00:55:28, Uri Blass wrote:
>
>>On November 27, 2002 at 23:45:47, Robert Hyatt wrote:
>>
>>>On November 27, 2002 at 15:44:03, Alastair Scott wrote:
>>>
>>>>On November 27, 2002 at 10:44:12, Richard Pijl wrote:
>>>>
>>>>>I had special detection code for rambling rooks in the Baron, but removed that
>>>>>in 0.99.3 as it fired wrongly in certain cases. This means that Baron 0.99.4
>>>>>beta 1 doesn't find the draw.
>>>>>
>>>>>Baron 0.36 (containing the rambling rook detection code) has no problem
>>>>>detecting the draw, it spots it immediately, showing Kxe3 as the PV. When backup
>>>>>up to the diagram position it doesn't show the draw anymore. The reason is that
>>>>>Baron considers 60..gxh3 a mistake, enabling the draw. Instead, Baron 0.36 will
>>>>>play 60..Rge2!
>>>>>
>>>>>I have been thinking a lot about a better way to detect perpetual check's but
>>>>>haven't implemented anything yet.
>>>>
>>>>You're right - I saw Rge2 immediately after I played Rh3, but Ruffian never even
>>>>considered it.
>>>>
>>>>But Crafty 19.1 comes up with a remarkable shot after 33 seconds (at 14 ply) -
>>>>60..Rg1+. I doubt very much whether any human player would ever dream up _that_.
>>>>
>>>>Interestingly, the right move is played for the wrong reasons; Crafty, up until
>>>>then, plays 60..gxh3 with a score of -6.5. It then moves to 60..Rg1+ with a
>>>>score of -10 without ever realising that gxh3 should have a score of 0 ;)
>>>>
>>>>Alastair
>>>
>>>
>>>I'm not understanding the crafty comment above.  If Rg1 is -10, and gxh3 is -6,
>>>I can see why it would prefer Rg1 over gxh3, so that white has g1 as a way out.
>>>But why would it want to play a move that leads to a draw when it can get a -10,
>>>which is good for black???
>>
>>The comment is that crafty does not see the draw
>>for gxh3 and prefers Rg1+ only because Rg1+
>>has a bigger advantage.
>>
>>This is what was considered as the wrong reason
>>by the poster.
>
>Couldn't have put it better myself :)
>
>This is proving a tricky position. For example, SOS plays ..gxh3 and doesn't
>seem to understand the position at all; it sees Rxe3+ but goes from 7 to 18 ply
>thereafter with a score of -6.6 ...
>
>Alastair

Isn't that natural since it will probably take 100 ply to see the draw?
Jim



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