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Subject: Re: Deep Blue Jr.

Author: Robert Hyatt

Date: 16:59:26 07/19/02

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On July 19, 2002 at 13:45:07, Uri Blass wrote:

>On July 19, 2002 at 13:16:06, Joshua Lee wrote:
>
>>I was wondering that if the DB team estimated a rating or over 300 points higher
>>than the programs at that time on equivalent hardware or equal search, they
>>weren't clear on that. That would mean 2796 on a P200 and Fritz 7 for example
>>wouldn't be anywhere near this on a P200. Has anyone seen anything about their
>>tests against commercial software and does anyone have any opinions about this?
>>
>>Granted that Software has improved and that on Todays Fastest Hardware The Top
>>Programs (provided the SSDF list is that accurate) is on equal footing with Deep
>>Thought and DB Jr.
>
>
>Why do you think that they may be only equal.
>I believe that the opinion of most programmers is that
>the top programs of today are clearly better
>than Deep thought and deep blue JR.
>
>It is known that their search algorithms were bad
>relative to what is known today
>(otherwise you could see people who copy their
>search algorithms with good results when I know that
>the people who tried to copy the way that they use
>singular extensions got bad results in games so
>they do not use it).
>
>It is known that they believed some wrong assumptions
>
>They believed that null move pruning is dangerous at
>their speed when the results say that null move pruning
>is only more productive when the machines are faster.
>
>They believed that the brute force depth is not very important
>at their speed and singular extensions are more important
>and they were again wrong(programs already
>have similiar speed to deep thought and they do not use
>singular extensions in the way that deep thought used them).
>
>Their speed simply misleaded them to wrong assumptions
>that they did not test.
>
>Uri


That last sentence is simply wrong.

On two counts...

1.  They tested _and_ wrote several papers on their search extensions.  It
was hardly "not tested".

2.  I have said this before.  You can accomplish the _same_ thing with
either selective extensions, or selective forward pruning.  There need be
_no_ difference in the two...  Assuming there is is theoretically incorrect.



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