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Subject: Re: Which is better?

Author: John Merlino

Date: 14:01:11 04/24/05

Go up one level in this thread


On April 24, 2005 at 16:49:55, Ricardo Gibert wrote:

>On April 24, 2005 at 16:45:12, John Merlino wrote:
>
>>On April 24, 2005 at 16:40:26, Ricardo Gibert wrote:
>>
>>>On April 24, 2005 at 16:28:06, Vincent Lejeune wrote:
>>>
>>>>On April 24, 2005 at 15:05:41, John Merlino wrote:
>>>>
>>>>>On April 24, 2005 at 14:31:52, Jack Lad wrote:
>>>>>
>>>>>>[d] 6nr/p2rkp1n/1pQRq1pp/1N2P3/8/4BN1P/PPP2PP1/2K4R w
>>>>>>
>>>>>>1.Nc7 or Nfd4?
>>>>>>
>>>>>>Or can they both mate in the same number of moves?
>>>>>
>>>>>Playing through the lines, it appears that:
>>>>>
>>>>>1.Nc7 is a Mate in 9.
>>>>>
>>>>>1.Nfd4 is a Mate in 11.
>>>>>
>>>>>jm
>>>>
>>>>3 best moves from ChessMaster 10 (AMD@3000+)
>>>>
>>>>Time	Depth	Score	Positions	Moves
>>>>9:38	1/13	Mate09	233251425	1.Nc7 Rxc7 2.Qxc7+ Kf8 3.Rxe6 Kg7
>>>>					4.Nh4 Ng5 5.Bxg5 Ne7 6.Bf6+ Kh7
>>>>					7.Qxe7 Rf8 8.Qxf8 fxe6 9.Qg7#
>>>
>>>You need to be careful with 1.Nc7. If CMX is anything like Ruffian, it will get
>>>a mate score, lose it, get it again only to lose it again while shifting from a
>>>best response to it of Rxc7, Nf8, Qf5 and Ngf6 all the while. Ruffian had a
>>>tough time with 1.Nc7. It took 5 times longer to reach the same depth of 14 that
>>1.Rxe6 got and ultimately lost the mate score.
>>
>>Chessmaster will never lose a mate score for the side to move. Once it reports a
>>mate, the only thing it can do is possibly report a shorter mate.
>>
>>Therefore, my "playing with the lines" (which you comment on in another post)
>>was merely to ensure that there was no shorter mate than the ones that The King
>>found relatively quickly.
>>
>>jm
>
>Okay. I did not know that CM enforced the property of never losing a mate score.
>Interesting.

In my opinion, no engine should report a mate score and then say "oops, I was
wrong, sorry...." :-)

jm



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