Author: Robert Hyatt
Date: 15:02:21 08/21/02
Go up one level in this thread
On August 21, 2002 at 15:18:02, Vincent Diepeveen wrote:
>On August 21, 2002 at 14:03:57, Robert Hyatt wrote:
>
>razoring = forwardpruning = fhr = dubiously throwing away
>branches.
Razoring doesn't "dubiously throw away branches." It simply reduces
the depth along _some_ branches by exactly 1 ply. The branch is _still_
searched... Just less deeply... For the same reason null-move is _not_
a forward pruning algorithm... nor is alpha/beta...
>
>>On August 21, 2002 at 08:20:07, Vincent Diepeveen wrote:
>>
>>>On August 21, 2002 at 07:58:52, Vincent Diepeveen wrote:
>>>
>>>needed to get more crafty versions?
>>>
>>>That all ain't octobre 1997...
>>
>>What is your point? razoring is _not_ "forward pruning". It
>>produces a somewhat similar result. the "last modified" doesn't
>>mean a thing, of course. That doesn't say _what_ was modified.
>>search.c is modified regularly.
>>
>>>
>>>/* last modified 04/01/99 */
>>>
>>>/*
>>> ----------------------------------------------------------
>>>| |
>>>| now we toss in the "razoring" trick, which simply says |
>>>| if we are doing fairly badly, we can reduce the depth |
>>>| an additional ply, if there was nothing at the current |
>>>| ply that caused an extension. |
>>>| |
>>> ----------------------------------------------------------
>>>*/
>>> if (depth<3*INCPLY && depth>=2*INCPLY &&
>>> !tree->in_check[ply] && extensions == -60) {
>>> register const int value=-Evaluate(tree,ply+1,ChangeSide(wtm),
>>> -(beta+51),-(alpha-51));
>>> if (value+50 < alpha) extensions-=60;
>>> }
>>>
>>>
>>>
>>>>On August 20, 2002 at 17:56:42, Robert Hyatt wrote:
>>>>
>>>>>On August 20, 2002 at 07:12:16, Vincent Diepeveen wrote:
>>>>>
>>>>>>On August 18, 2002 at 21:48:08, Robert Hyatt wrote:
>>>>>>
>>>>>>>On August 18, 2002 at 21:15:47, Vincent Diepeveen wrote:
>>>>>>>
>>>>>>>>On August 18, 2002 at 15:08:49, Gian-Carlo Pascutto wrote:
>>>>>>>>
>>>>>>>>>On August 18, 2002 at 09:06:02, Jorge Pichard wrote:
>>>>>>>>>
>>>>>>>>>> Kasparov proved that he can defeat programs at fast time controls when he
>>>>>>>>>>defeated Deep Thought in a game/90 two games match in 1989. This program was
>>>>>>>>>>weaker than Deep Junior is today, as it searched well over 2,000,000 NPS, but
>>>>>>>>>>didn't have as much chess knowledge as Deep Junior. He also defeated Deep Blue
>>>>>>>>>>in 1996. This program is obviously much faster than Deep Junior is today, but in
>>>>>>>>>>my opinion Deep Junior still has more chess knowledge than Deep Blue had back in
>>>>>>>>>>1996.
>>>>>>>>>>
>>>>>>>>>>PS: It is hard to compare Deep Blue of 1997 vs Deep Junior of today, but in my
>>>>>>>>>>opinion Deep Junior Chess Knowledge could make up for the difference of Deep
>>>>>>>>>>Blue super calculating power of 1997.
>>>>>>>>>
>>>>>>>>>How do you know all this?
>>>>>>>>>
>>>>>>>>>How do you know Deep Junior has more chess knowledge?
>>>>>>>>>
>>>>>>>>>I mean, we don't know what Deep Blue evaluated exactly (save a few things
>>>>>>>>>that are published). We know *nothing* about what Deep Junior evaluates
>>>>>>>>>exactly.
>>>>>>>>
>>>>>>>>yes we know that. Look at the paper it describes about 40 patterns and if
>>>>>>>>you multiply that with arrays of 64 (that's how it goes in hardware)
>>>>>>>>and add to it piece square tables it is exactly what theydid. of course how
>>>>>>>>well defined the patterns are is a different case.
>>>>>>>>
>>>>>>>>We can see that at the rude play very easily. Look at game 1 from 97,
>>>>>>>>where it played manoeuvres like qa5 bc7 qc5 which even seirawan comments
>>>>>>>>correctly in his 1997 analysis. Gnuchess accuracy it is. Very rude and
>>>>>>>>primitive, but for a program with a leaf evaluation (even though some
>>>>>>>>tuning by preprocessor took place) with several tens of patterns (and
>>>>>>>>as a result of that several thousands of adjustable parameters) that
>>>>>>>>means it was searching deeper than any program with that amount of
>>>>>>>>knowledge in evaluation in 1997. I for sure had more in 97 (though i
>>>>>>>>used arrays less back in 97 than i do now as i'm not hardware but
>>>>>>>>software and L2 caches were performing bad in general back then until
>>>>>>>>pentium pro which took a few years to adjust to) so had others, but we
>>>>>>>>all shared that at a 200Mhz pentiumpro we searched 8-9 ply, NOT 11-12.
>>>>>>>>
>>>>>>>
>>>>>>>I'm not going to comment on the rest of your nonsensical statements, but
>>>>>>>the above is clearly wrong and that is provable. I played in Jakarta on
>>>>>>>a pentium pro 200. And _My program_ searched 11-12 plies. I have the logs
>>>>>>>to prove it. And anyone that wants to download the crafty (jakarta) version
>>>>>>>can find the same thing...
>>>>>>>
>>>>>>>So if you are going to make statements, at _least_ verify that there is some
>>>>>>>basis of truth to them first. _you_ might not have been able to hit 11-12
>>>>>>>plies on a P6/200, but I did... And others did as well.
>>>>>>
>>>>>> - no checks in qsearch
>>>>>> - forward pruning last ply which also hurted nullmove incredible
>>>>>
>>>>>Don't know what you mean there. If you are talking about razoring, it was
>>>>>a 25% gain roughly but it was removed many years ago...
>>>>
>>>>Yes it was removed around 2000-2001 after i adviced you to remove it Bob.
>>>>
>>>>>> - no mating extensions (not solving win at chess 141 even soon which
>>>>>> in 1997 was a 9 ply trick for me).
>>>>>
>>>>>Crafty has been solving wac141 for a long time. The null-move mate threat
>>>>>speeded it up a ply, maybe...
>>>>>
>>>>>But that is not the point... You said "nobody got to 11-12 plies". I got
>>>>>to 11-12 plies. Your statement is therefore simply false because of that.
>>>>
>>>>A dubious 11-12 ply which doesn't compare to them doesn't count.
>>>>
>>>>Look DIEP 1997 was comparable, so was gnuchess or Zarkov, so was
>>>>The King. When forward pruning turned off (except nullmove) in the king
>>>>from that period, neither of all the programs ever got 11-12 ply.
>>>>
>>>>We can't count an idiotic crafty version. Crafty in 1997 didn't have
>>>>anything called 'king safety'. I remember how you did effort to prevent
>>>>getting mated by something stupid where even diep version 1.0 didn't
>>>>fall for at bullet search depths back then, and where crafty fell for
>>>>even at 11-12 ply. You had a special feature at icc created to prevent
>>>>that 'mercilous' attack even. Everyone in blitz and bullet could beat
>>>>crafty very long period of time with just a simple king safety trick which
>>>>even 1400 chessplayers understood. They were noplayed, censored, a special
>>>>S list was created, anything but the king safety was fixed.
>>>>
>>>>If you run with material only, every idiot gets 11-12 ply. Now you didn't
>>>>even get it in a legal way. You needed forward pruning for it.
>>>>
>>>>Your memory is FUCKING bad that you don't even remember when you turned
>>>>off the forward pruning in crafty.
>>>>
>>>>>You didn't qualify the "nobody to exclude those that can't solve wac 141
>>>>>fast enough for you or whatever."
>>>>>
>>>>>
>>>>>
>>>>>>
>>>>>>Fritz3 also got 11 ply but it was also with a lot of dubiousy.
>>>>>>
>>>>>>In fact some hit 15 ply as well with major forward pruning back then.
>>>>>>
>>>>>>But that is not a fair compare. We must compare programs that searched
>>>>>>in the same way Bob. So not forward pruning, at most nullmove. and
>>>>>>strong in the leaves.
>>>>>>
>>>>>>Crafty even today is very weak there.
>>>>>
>>>>>Where does that leave _your_ program then???
>>>>>
>>>>>
>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>>So then 11-12 wins simply. 8-9 with evaluations from that period lost
>>>>>>>>simply. period.
>>>>>>>>
>>>>>>>>Evaluations 8-9 nowadays are a different case (extending way more nowadays
>>>>>>>>too than in 1997 too). The evaluation of DIEP is a top grandmaster relatively
>>>>>>>>seen when compared to 1997 where it knew shit from endgames for example.
>>>>>>>>
>>>>>>>>>As a consequence, you can't possibly support any of the claims or
>>>>>>>>>suggestions you make.
>>>>>>>>
>>>>>>>>Yes we can. The biggest evidence is the games played. Statistical evidence
>>>>>>>>on how programs play moves is the best. The major problem is that you need
>>>>>>>>to invest time if your chess level is not so high to see it and even a high
>>>>>>>>rated chessplayer who knows nothing from how chessprograms evaluate will
>>>>>>>>completely fail here (though Seirawan came pretty far but as he was paid
>>>>>>>>by IBM he described it in a positive way, leaving conclusions to the reader).
>>>>>>>>
>>>>>>>>We have seen some marvellous conclusions already by Uri here based upon
>>>>>>>>logfiles from the IBM computer. From evaluation viewpoint we
>>>>>>>>see for example from the mainlines that it gives a big bonus for a bishop
>>>>>>>>attacking its own queen. We also see it only cares for how many squares the
>>>>>>>>queen can go to, not caring for patterns there. Very basic things which
>>>>>>>>were at the time very normal in gnuchess type programs.
>>>>>>>>
>>>>>>>>We also see that it knows really nothing from good/bad bishops (not
>>>>>>>>surprising, only 1 program had in 97 this thing and it was mine). It
>>>>>>>>simply didn't care for the center at all. This is amazing nowadays
>>>>>>>>comercial programs *only* care for the center.
>>>>>>>>
>>>>>>>>Also its knowledge on passers was very primitif. We see for example that
>>>>>>>>it doesn't see difference even between covered passers and very good
>>>>>>>>blocked passers. Regrettably that didn't happen a lot on the board.
>>>>>>>>
>>>>>>>>The most amazing thing by far is its huge penalties and bonuses for a few
>>>>>>>>king safety things. that of course led to big patzer play which is nice
>>>>>>>>and nowadays very normal. These penalties/bonuses are in complete
>>>>>>>>contrast to pawn structure aroudn the king. In many games we see
>>>>>>>>major mistakes here. game 1, but if i remember well game 4 where
>>>>>>>>deep blue castles long and then plays horrible king moves and b4 b5.
>>>>>>>>
>>>>>>>>From the many king moves in the game and in the logfiles we see clearly that
>>>>>>>>it had a very primitif 'opponent pieces to my king' distance feature.
>>>>>>>>
>>>>>>>>I remember how DIEP back in 95,96 wanted also always ka1 because that would
>>>>>>>>mean the king is further away from the pieces. A very basic mistake we
>>>>>>>>still see in some engines. It is a non-preprocessor mistake obviously.
>>>>>>>>
>>>>>>>>but it doesn't take away that the pattern is a very primitive heuristic.
>>>>>>>>
>>>>>>>>nearly all kind of bad moves are explained by simple bugs in evaluation.
>>>>>>>>100% the exact bugs gnuchess also has.
>>>>>>>>
>>>>>>>>the comparision with gnuchess is not fair, but for evaluation it sure is.
>>>>>>>>
>>>>>>>>We see that the 'new gnuchess', sorry to call it like that, zarkovx,
>>>>>>>>is the program which when getting 10-11 ply is playing from all chess software
>>>>>>>>nearly exactly every move which deep blue also played. don't use the
>>>>>>>>dos-zarkov, but i mean the 4.5xx versions of zarkovx where John hardly
>>>>>>>>nullmoves the last few plies (they take some time to get 10-12 ply,
>>>>>>>>horrible branching factor). It makes the same weird moves, same mistakes,
>>>>>>>>same strong moves. It is a perfect match for how deep blue played.
>>>>>>>>
>>>>>>>>A person who can't play chess at all and whose program is exactly making
>>>>>>>>the mistakes a beginner makes when making a chess evaluation.
>>>>>>>>
>>>>>>>>Best regards,
>>>>>>>>Vincent
>>>>>>>>
>>>>>>>>>All of this talk about Deep Blue this and Deep Blue that is just pure
>>>>>>>>>bullshit. Maybe Fritz 7 would kick its ass. Maybe Fritz 7 would get
>>>>>>>>>its ass kicked. Maybe they're about as strong. I dont care either way
>>>>>>>>>since Deep Blue doesn't exist anymore and it certainly doesn't look as
>>>>>>>>>if it's ever going to play again. So why care about it? Why keep making
>>>>>>>>>totally unfounded speculations? What's the frigging point? This kind
>>>>>>>>>of discussion comes up about once in every 2 months and there has NEVER
>>>>>>>>>EVER come anything insightful out. Instead, a lot of people are making
>>>>>>>>>claims or saying things that they can never ever support, or even are
>>>>>>>>>demonstrably wrong.
>>>>>>>>>
>>>>>>>>>Mention the words 'Deep' and 'Blue' to anyone who works in computer
>>>>>>>>>chess, and all sanity suddently grinds to a halt.
>>>>>>>>>
>>>>>>>>>--
>>>>>>>>>GCP
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