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Subject: Re: What is the public's opinion about the result of a match between DB and

Author: Robert Hyatt

Date: 10:37:02 04/24/01

Go up one level in this thread


On April 24, 2001 at 11:25:29, Vincent Diepeveen wrote:

>On April 24, 2001 at 09:57:39, Robert Hyatt wrote:
>
>>On April 24, 2001 at 08:20:57, Vincent Diepeveen wrote:
>>
>>>On April 24, 2001 at 03:47:15, Uri Blass wrote:
>>>
>>>>the best software that is not IBM.
>>>>
>>>>Suppose there is a match of 20 games at tournament time control
>>>>
>>>>I am interested to know how many people expect 20-0 for IBM
>>>>How many people expect 19.5-.5?....
>>>
>>>>If IBM expect to do better result then the average result that the public expect
>>>>then they can earn something from playing a match of 20 games with Deep Blue.
>>>>
>>>>I believe that a part of the public who read the claim that kasparov played like
>>>>an IM are not going to expect good result for IBM.>
>>>>Uri
>>>
>>>First of all IBM would get out of book every game with -1.0 pawn
>>>disadvantage (which is about the average of what Kure and Noomen
>>>get in tournaments, sometimes they get out of book with mate in XXX even).
>>
>>That is pretty funny.  I use a very simple to create book, and I don't get
>>out of book that badly in _every_ game.  Not even every other game.
>>
>>
>>
>>>
>>>I would expect IBM to lose with 18-2.
>>>
>>>Let's be realistic
>>
>>
>>Yes, let's.  :)  18-2 is pretty funny.
>>
>>
>>
>>>
>>> a) IBM searched 11-13 ply in 97, nowadays programs search deeper
>>
>>
>>Every time you make that statement I am going to correct it.  From the log
>>files of the 1997 match we _know_ they searched 15-17 plies deep.  Not 11-13.
>
>First of all the search depth *shows* 11 to 13 ply at most.

No it doesn't.  Here is yet another log excerpt from an early middlegame
position:

 5(5)[axb5](60) 60  T=1
pa4b5P Pa6b5p ra2a7 Ra8a7r bc5a7R
 6(5)[axb5](57) 57  T=1
pa4b5P Pa6b5p ra2a7 Ra8a7r bc5a7R
 7(5) #[axb5](51)##################################### 51  T=2
pa4b5P Pa6b5p ra2a6 Ra8a6r ra1a6R Nd6b7 bc5e3 Rc8a8
 8(6) #[axb5](46)##################################### 46  T=7
pa4b5P Pa6b5p ra2a6 Nd6b7 bc5e3 Nb7d6 ra6a7 Bf8e7
 9(6) #[axb5](49)#################################### 49  T=55
pa4b5P Pa6b5p ra2a6 Nd6b7 bc5b6 Ra8a6r ra1a6R Nb7d6
10(6) #[axb5](49)##################################### 49  T=160
pa4b5P Pa6b5p ra2a6 Nd6b7 bc5f8B Qe8f8b ng3f5 Ra8a6r ra1a6R Rc8b8
11(6) #[axb5](49)#[Nf5](50) 50  T=308
ng3f5 Nd6f5n pe4f5N Pb5a4p bc2a4P Bd7a4b ra2a4B Qe8d7 bc5f8B Rc8f8b pf5f6 Qd7d5p
qf2g3 Pg7g5
---------------------------------------
-->  33.   Nf5 <-- 7/65:41
---------------------------------------

Again I reiterate, the notation 11(6) means 11 plies in software search,
6 plies in the hardware, plus the quiescence in hardware.  There is _no_
argument with this.  Simply ask any of the DB guys.  11(6) is a total of
17 plies of search.


>
>Secondly it is theoretic impossible to search 19 ply fullwidth (13 ply
>software + 6 ply hardware) without hashtable last 6 plies.


no it isn't.  And I will be glad to show you a 19 ply search by Crafty if
you want.  Might take a while, but it is _not_ "theoretically impossible".
It is theoretically possible to solve the game, in fact...





>
>This is simple math.
>
>how bigtime it suffered from not using hashtable can be easily
>seen in game 2 for example.

You need to try the experiment first.  I did so a few years back when having
a discussion with Hsu.  It doesn't hurt nearly as much as you think.  Even
Junior doesn't store the last ply or two before q-search.  It hurts less in
the middlegame, more in the endgame, but not by a huge amount...  the test is
easy to do (for me anyway).




>
>One of the moves Be4 which it made where Kasparov shortly was of
>the opinion that deep blue team 'cheated'. There there are many
>transpositions possible. Despite that deep blue doesn't search
>deeper as in openings positions where there are little
>transpositions possible.


Your math isn't working here.  The effective branching factor at the Be4
position is _still_ quite high.  It is not a simple endgame yet.

>
>I think Kasparov later corrected that, but i'm not sure of it.
>
>In diep the average number of moves is 40 in middlegame on average
>(endgame of course not counted). That is because it sees
>many stupid nonsense moves which humans do not consider soon.
>
>With hashtable you would reduce that bigtime (or as you indicate
>reduce actually seach depth needed, whatever you do, you will get
>a better b.f. as result).
>
>Last of all i DID do experiment with DIEP searching fullwidth and not
>using last 6 ply hashtable.
>
>Could you do this with crafty too? Of course after you also added SE
>to it for the first so many ply minus 6 and also turn on more recapture
>extensions and turn on checks in qsearch to some extend (for example
>only first ply).
>
>Now we can compare. Please posts nodes and search depth needed.
>
>The good b.f. which DB seemingly has first few seconds
>is a result of that initially it can't put 480 chessprocessors
>to work very efficiently within a few seconds.

Sorry, but DB used 480 chess processors for _every_ search it did.  That was
the way the algorithm was written.  As a result, its search (and branching
factor) for early plies was worse than for deeper plies.  This all explained
by Murray several times.



>
>Nevertheless, please do the experiment and report back. For diep i need
>billions of nodes for 10 ply already!

I'll try to find my old data on this.  But if you need billions of nodes,
something is broken.  I can turn hashing _off_ and not need billions of nodes
to search 10 plies...




>
>And i'm pretty sure i sort my moves better as Deep Blue ever did!
>Not to mention my evaluation is way better!


I love statements of pure subjective opinion when given as uncontestable
fact...  Since you have never seen their evaluation in particular...




>
>All those factors are completely irrelevant of course. The proof for
>their search depth is so obvious!
>
>Apart from that studying logfiles you see that they get fail high to
>some tactical moves at very explainable search depths.
>
>Like the tactical move Bf5 in game 6 is 8 ply for them. With recaptures
>and SE i also need 8 ply for that. In fact most programs which by default
>do recaptures already need 8 ply!
>
>>15-17 in the middlegame, more in the endgame.  I don't know where you get the
>>11-13 nor why you keep saying it when the log files clearly show that is wrong.
>
>6 ply in hardware + 13 ply in software = 19 ply fullwidth.
>Not 15-17. 11-13 ply is what they got. If you would add 6 ply in hardware
>to that that's 17-19 ply fullwidth!


That is _exactly_ what they got.  11(6) _does_ mean 17 plies + q-search.  I
am not certain that the last 6 plies was 100% fullwidth...  that I don't know
and I haven't taken the time to ask them for real details.  They did mention
futility pruning in the hardware, so perhaps some of the last 6 plies were
subject to this.  Or perhaps just the q-search was using futility.  But there
are numbers in the log that match what they have said.  I don't see any way to
dismiss (a) log files and (b) direct statements from the team members.

>
>We only get that with nullmove AND hashtables!
>
>Please do the experiment Bob and as only programmer defending
>Deep Blue here it's very obvious that the facts are hard to ignore!


It seems to me that you are doing a pretty good job of "ignoring the
facts" here.  Facts given directly in the log files for example concerning
their search depth.

I often reach depths of 14-15 in middlegame positions using null-move.  Turn
it off and that drops by 2-3.  But then make me 200 times faster and I gain that
back and _then some_.




>
>>
>>
>>> b) their book is hell worse as nowadays books are
>>> c) positionally it never was good, it doesn't even
>>>    know what a good bishop is nor when a doubled pawn is
>>>    good (f2,g2,g3 pattern happened twice in games against kasparov)
>>>    also it exchanges sometimes queens in a position where not exchanging
>>>    wins for IBM
>>
>>Let me know when you or your program beats Kasparov in a standard game.  Or
>>even when you _draw_ him.  Then tell me how weak they played positionally.
>>
>>
>>
>>> d) hardly can use EGTBs
>>
>>
>>"Hardly"???  used them just like I do.  They used them _before_ I did in
>>fact.  They were using them in the late 1980's.  Just like HiTech did.  And
>>others.
>>
>>
>>
>>
>>>
>>>So in *all* respects it is getting outgunned. Not to mention EGTBs.
>>>
>>>No one talked about that subject yet, but last so many plies they can't
>>>use EGTBs. They only can use them the first 5 or 6 ply, that's it.
>>
>>
>>They use them in the first 11-13 plies.  Which is _exactly_ how I use them.
>>I don't probe in the q-search.  I don't probe beyond the basic nominal search
>>depth.  It works fine for me.  It works fine for them.  They don't do it in
>>the hardware part of the search, which means the last 4-6 plies plus q-search.
>>That is _not_ a problem since it works well for me.
>>
>>
>>
>>
>>
>>>
>>>Though this is very good compared to not using them, this means simply
>>>that all exchanges towards a lost 5 men they will not detect.
>>
>>And if you probe in the q-search you will get killed tactically when there
>>are only 6-10 pieces on the board.  You will lose _several_ plies.  I know.
>>I have been there.
>>
>>
>>
>>
>>>
>>>They lose with induction to everything. The level of software has increased
>>>bigtime when compared to 1997. Of course the strategical problems are
>>>still there and some positional problems are still there, but in
>>>computer-computer games you hardly can take advantage of that. Only
>>>a human versus a computer can!
>>>
>>>Best regards,
>>>Vincent
>>
>>
>>
>>Your "induction" is broken.  Make that "non-existent".  HiTech or Cray Blitz
>>won't lose to "everything" today by any wild stretch.  Much less Deep Blue.
>>
>>The jealousy directed at this program/project by chess programmers (some anyway)
>>is remarkable...  the speculation about how it operates is even more remarkable.
>>And finally the amount of disinformation about it is unbelievable.



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