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Subject: Re: ACM1994

Author: Robert Hyatt

Date: 10:16:35 09/20/05

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On September 20, 2005 at 12:59:03, Uri Blass wrote:

>On September 20, 2005 at 11:58:35, Robert Hyatt wrote:
>
>>On September 20, 2005 at 02:35:50, Bruce Moreland wrote:
>>
>>>On September 18, 2005 at 14:47:26, Robert Hyatt wrote:
>>>
>>>>On September 18, 2005 at 14:38:27, Uri Blass wrote:
>>>>
>>>>>On September 18, 2005 at 13:59:18, Robert Hyatt wrote:
>>>>>
>>>>>>On September 18, 2005 at 12:00:09, Vincent Diepeveen wrote:
>>>>>>
>>>>>>>On September 18, 2005 at 10:45:19, Robert Hyatt wrote:
>>>>>>>
>>>>>>># Name 1 2 3 4 5 P BU SB G
>>>>>>>1 Deep Thought II 2w1  5b0  7w1  3b1  5b1  4  13½ 11  5
>>>>>>>2 Zarkov          1b0  6b1  4w1  5b=  3w1  3½ 15  9¾ 5
>>>>>>>3 Star Socrates   10w1 7b1  5w1  1w0  2b0  3  12½ 5  5
>>>>>>>4 Now             6w=  10b= 2b0  8w1  9b1  3  10½ 5½ 5
>>>>>>>5 Mchess Pro      8b1  1w1  3b0  2w=  1w0  2½ 16½ 7¾ 5
>>>>>>>6 Cray Blitz      4b=  2w0  9w1  7b0  10w1 2½ 11  4  5
>>>>>>>7 Wchess 9w1      3w0  1b0  6w1  8b0       2  13½ 4½ 5
>>>>>>>8 Evaluator       5w0  9b0  10w1 4b0  7w1  2  10  2½ 5
>>>>>>>9 Innovation II   7b0  8w1  6b0  10b1 4w0  2  10  2½ 5
>>>>>>>10 Spector        3b0  4w=  8b0  9w0  6b0  ½ 12½ 1½ 5
>>>>>>>
>>>>>>>Zarkov from those days had no problems beating your 3 million nps Cray Blitz.
>>>>>>>Nor had Wchess problems beating your 3 million nps Cray Blitz.
>>>>>>>
>>>>>>
>>>>>>Ask John about the game.  First, this was a 500K program for rounds 2-4.  And
>>>>>>when you ask him, he'll tell you about our rather severe crash problem due to a
>>>>>>missing test to limit ply to 64 or less.  And in a couple of cute places, we
>>>>>>went beyond that limit, crashed, and burned.  We fixed it for the last round,
>>>>>>but it really didn't matter to the final results.
>>>>>>
>>>>>>But notice the issue was about deep thought, _not_ about Cray Blitz.  Did you
>>>>>>see any of the micros coming close?  (hint:  round 2 was a forfeit which is why
>>>>>>they were paired a second time, round 2 never got started for the DT MCP game).
>>>>>
>>>>>Deep Thought was significantly better than the micro of 1995
>>>>>
>>>>>Uri
>>>>
>>>>I am well aware of that.  And DB was 100x faster than deep thought 2, and also
>>>>had a better evaluation...
>>>>
>>>>that was my point in all this...
>>>
>>>I think that Hsu is a pretty arrogant person, after having read some stuff that
>>>he has said about himself and other chess programmers.
>>>
>>>Read his book, if you can stand it.
>>
>>I did.  It didn't particularly turn me off.  But then I have had dozens of
>>face-to-face conversations with him dating back to 1987 in Orlando at the ACM
>>event that year, continuing thru the point where he left IBM a few years back.
>>
>>>
>>>For years you have taken a few things he has said as truth, but given his
>>>personality I am not sure if they are true.  He may think they are, but this
>>>doesn't mean that they are.
>>
>>That is probably all in perception.  I took very little of what he said at face
>>value, without supporting evidence.  He was usually more than happy to sit down
>>with deep thought and play with positions to see how it would react.  And he
>>never wanted to "hide" the display so I could not see.  I didn't trust the SE
>>data, since they gave conflicting reports on the effect (was it +70 or +7 rating
>>points better) so I simply tried it for myself in Cray Blitz.  And I think that
>>+7 was closer to the truth although in the right positions it was much more than
>>that...
>>
>>
>>
>>
>>>
>>>He hung you out to dry by leaving you as primary defender of Deep Blue for
>>>years, while he left the trivialities of computer chess to mere mortals like us.
>>> The DB project doesn't deserve defense.  It hit computer chess like a
>>>carpetbagger, then left in the night when the money was gone.
>>>
>>>bruce
>>
>>
>>However, I would not attribute that to Hsu or Campbell.  They were active in
>>computer chess for many years.  IBM pulled the plug for obvious reasons after
>>they hit the peak of Mt. Everest...
>>
>>I'll always have a great deal of respect for the group.  PVS search was first
>>used in my program by accident, as Murray and I played with it at an ACM event
>>on a machine we were not using, but a machine we had to use due to a power loss
>>during a key round.  Singular Extensions was Hsu's idea, and it certainly
>>worked, since many are using it today in various forms.
>
>I know nobody who use it in the way that Hsu used it.
>
>Uri


Several have used PV-singular as defined by Hsu.  Kittinger was one, Lang was
another.  I'm not sure anyone did the FH-singular extension as defined by Hsu
because it is _very_ costly.  But I did it in Cray Blitz and it worked just
fine.  I tried it in Crafty and it didn't work just fine.  Whether that was a
result of the null-move stuff with R=2/3, vs Cray Blitz with R=1, I don't really
 know since I was not interested in crippling Crafty's search to try them
further...

One day I might, again...

However, just because no one did FH-singular doesn't mean the idea is wrong.  No
one does it because of the cost.  When you are 1000x faster than your nearest
competitor, you can give up a factor of 10x to implement something like that,
and _still_ be 100x faster than them which is more than enough to avoid
trouble...

People copy ideas that work well with low cost, they often avoid things with
high cost because that cost will more than offset the gain if you don't have
special-purpose hardware to hold the cost down.  I could make a list of a few
key endgame features that appeared in Crafty before they were in any commercial
programs.  Outside passed pawns in 1995 is one.  Then candidate passed pawns
(distant majorities).  etc.  If you go back to 1976 and "blitz" we had the
"passed pawn race" code already in place so that we could detect uncatchable
passed pawns in king and pawn endings.  Most everyone does that today.  Because
the costs are more than offset by the gains.  FH-singular might not be there
yet, but that is why no one is using it, not that it does not work.  Because it
is clearly correct theoretically.  Just too expensive practically...




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