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Subject: Re: SEE for forward pruning in Q. Search and nullmove cooking problems

Author: Vincent Diepeveen

Date: 03:35:13 08/13/99

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On August 12, 1999 at 14:33:59, Robert Hyatt wrote:

>On August 12, 1999 at 13:32:06, Vincent Diepeveen wrote:
>
>>On August 12, 1999 at 09:47:51, Robert Hyatt wrote:
>>
>>>On August 12, 1999 at 08:32:02, Vincent Diepeveen wrote:
>>>
>>>>On August 12, 1999 at 01:33:35, Dave Gomboc wrote:
>>>>
>>>>>On August 12, 1999 at 01:10:14, blass uri wrote:
>>>>>
>>>>>>This example shows that the null move is not a very good idea.
>>>>>>If you need more 3*2=6 plies to see the right move and there is no
>>>>>>zunzwnag(playing no move cannot help black) then you are not close to see
>>>>>>everything to depth n-r with null move.
>>>>>>
>>>>>>I thought depth n when you use null move with R=2 means that except for
>>>>>>zunzwangs you analyse everything to depth n-2 and I see that it is not the case.
>>>>>>
>>>>>>Uri
>>>>>
>>>>>Well, null-move is as you described, but what is shown above is "recursive
>>>>>null-move", which seems to be pretty popular, and some people abbreviate
>>>>>this as simply "null-move".  It is the sort of search algorithm that gives
>>>>>people a happy feeling inside about how deep they are searching, but leaves
>>>>>holes for programs like DB to drive a truck through.  Of course, Bob has pointed
>>>>>this out more than once before.  Consider how much is being chopped out of some
>>>>>13 ply search, and you might agree that Bob isn't just being stubborn: there's
>>>>>actually quite a big difference in coverage.
>>>>>
>>>>>Of course, those who use recursive null-move are making the reasonable gamble
>>>>>that the extra coverage isn't beneficial at their search speeds.
>>>>>
>>>>>Dave
>>>>
>>>>Now this is pure BS. Even at 5 0 Deep blue gets kicked silly by a laptop.
>>>
>>>
>>>total bullshit.
>>
>>>no counter-argument needed.  When was the last time you beat my program?  My
>>>program can't beat Cray Blitz.  Cray Blitz couldn't beat Deep Thought.  Blitz
>>>or tournament.
>>
>>Well there are a lot of eyewitnesses of the following:
>>
>>Rebel beating Anand
>
>Rebel lost 1.5-.5 in 40/2 time controls.  Deep Blue beat _Kasparov_ in a
>6 game match at 40/2 time control.  What does this have to do with a micro
>beating deep blue?
>
>
>
>>Rebel beating deep blue junior at a small laptop.
>
>Rebel didn't play "deep blue junior" as I have already explained.  It played
>a stateless web-based version that was playing _lots_ of simultaneous games
>all over the world.  It is a favorite IBM demo site that is always busy.  Hsu
>thought that it might be a 2200-level player at first, but later revised that
>estimate downward because of all the simultaneous users hitting on it at the
>same time via the web.
>
>Get off of this kick.  I have seen them play micros at ACM events.  I have
>seen them play GMs at ACM events.  I watched them put together the best-ever
>win/lose ratio on ICC, playing the strongest GM players there, at _any_ blitz
>time control they wanted (ie 2 12 which is far from blitz, yet they put everyone
>away, maybe losing 1 game at blitz out of 141, with no weak players in the mix).
>
>
>
>
>>Shredder beating Rebel in paderborn.
>>
>>Now deduction:
>>
>>DB junior is a laptop version of deep blue. Rebel played at
>>a laptop against DB.
>
>
>DB junior isn't a 'laptop'.  Where do you get your information?  It is a
>single-processor SP workstation, accessed via a web browser.  It is fed
>positions, it responds with moves.  It knows nothing about 'games' but only
>about positions it is given.  It was put together as a demo.  That is all that
>it is.  It was _not_ advertised as the normal deep-blue junior machine.  The
>real DB junior has had quite a career beating GM after GM in demonstration
>matches around the world.  In fact, no GM has beating it in a 'match' so far
>that I am aware of.
>
>
>
>
>
>>
>>Shredder beating Rebel chanceless in world champs,
>>So shredder beating Deep Blue chanceless.
>
>
>
>what utter nonsense.  The Yankees beat the Braves, The Braves beat the
>Phillies, the Phillies beat the Yankees. Your theory is shot...
>
>
>
>
>>
>>Not very surprising for 'depth' fanatics like you either,
>>as Deep blue just gets 11 or 12 ply, and shredder regurarly got
>>to 15 ply in paderborn.
>
>different plies.  No null move.  No forward pruning.  No tactical mistakes.
>I'd take 12 plies with no null move any day I could get it.  Because I have
>_seen_ them play chess.  I have seen them beat a program (Cray Blitz) that
>can clean your clock any day of the week.  I have seen them do this 3 times.
>Seeing tactical shots 10-20 plies _before_ CB would see them.
>
>You can claim that they are inferior all you want.  But you can count the
>games they have lost to micro computers on one hand, and have plenty of fingers
>left over to scratch your head in amazement with.
>
>
>
>
>
>>
>>So it just gets outsearched positional completely.
>
>
>Yes...  so badly that it doesn't lose to other computers, to humans,  heck,
>it might not even be able to beat or draw itself...
>
>
>
>>
>>Secondly i played myselve against deep blue junior, andit
>>played positional so bad (tactical it played perfect),
>>that with a lot of manoeuvring i got it play all kind of
>>crap pawn moves, which even a 3 ply search in DIEP would not
>>have make it play such horrible moves.
>
>
>you played against the web-based toy.  Ask Dlugy about DB junior.  He worked
>with them for a good while.  Ask Benjamin.  Or Byrne.  Etc.  You might discover
>they have a _totally_ different opinion.
>
>
>
>
>>
>>Anyway. All facts together leads to deduction:
>>
>>Shredder beats Deep Blue chanceless.
>
>
>Sometimes you make a lot of sense.  Other times you make a lot of nonsense.
>Unfortunately, you are doing the latter and not the former here.  You've never
>seen them 'in person'.  So you have no idea what you are talking about.  I'm
>reminded of a famous quote:

At Paderborn there were never more than 2 terminals showing DB junior.
It was with BIG Capitals. It's main problem and weakness was that it
played without book obviously. Most of the times replying d5.

It searched for a lot of seconds a move.

First move about 14 seconds. It had its own time display. So lag or
network delay didn't matter. I had to wait sometimes if bad luck for
a minute, and it showing it had thought only for a few seconds.

if IBM with big capital colorful letters says DEEP BLUE JUNIOR,
then why do you argue that?

Does IBM LIE?


>  "it is better to remain silent and be thought a fool, than to open your
>   mouth and remove all doubt..."



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