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Subject: Re: No Winboard problems here. Crafty/Comet

Author: Robert Hyatt

Date: 18:42:31 06/02/98

Go up one level in this thread


On June 02, 1998 at 21:40:42, Robert Hyatt wrote:

>On June 02, 1998 at 17:15:04, Komputer Korner wrote:
>
>>On June 02, 1998 at 12:58:48, Robert Hyatt wrote:
>>
>>>On June 02, 1998 at 10:47:02, Ulrich Tuerke wrote:
>>>
>>>>On June 02, 1998 at 10:12:30, Robert Hyatt wrote:
>>>>
>>>>>On June 02, 1998 at 02:01:43, Komputer Korner wrote:
>>>>>
>>>>>>On June 02, 1998 at 00:51:08, Havergal Brian wrote:
>>>>>>
>>>>>>>This is part of my Winboard.ini file.  So far I've had no
>>>>>>>crashes/problems.  Just put this in the appropriate spot with
>>>>>>>the changes you want.
>>>>>>>
>>>>>>>/cp
>>>>>>>/mg 50
>>>>>>>/sgf wcraftyvscomet
>>>>>>>/fcp="comet-wb.exe"
>>>>>>>/scp="wcrafty-12_6 xboard"
>>>>>>
>>>>>>Since I turned pondering off, no more crashes but I still have the
>>>>>>problem of Crafty corrupting it's book after a long natch of 40 games. I
>>>>>>have to rebuild it's book each time. There is definitely something
>>>>>>broken with Crafty's book code because in my latest match Crafty was out
>>>>>>of book after 1.e4e5 2.Nf3 !!!!!!
>>>>>>--
>>>>>>Kpmputer Korner
>>>>>
>>>>>
>>>>>lets back this trolley up a bit.  So far as I can tell, there is
>>>>>*nothing*
>>>>>wrong with crafty's book code.  It is *impossible* for it to corrupt the
>>>>>book, because it never adds anything to the book at all.  If it were
>>>>>doing
>>>>>this, we'd be seeing *lots* of problems on the servers where we play 500
>>>>>games
>>>>>a day on each program...  The problem most likely lies somewhere in your
>>>>>setup, whether you have flakey memory, or something else, is unknown.
>>>>>But
>>>>>I played one 330 game match yesterday crafty vs crafty with *zero*
>>>>>problems
>>>>>of any kind...
>>>>>
>>>>>Be careful of "there is definitely something broken with crafty's book
>>>>>code."  as the evidence doesn't support that when everyone else seems to
>>>>>be able to play crafty vs xyz with no problems...
>>>>
>>>>I have had a similar (the same ?) effect when playing Crafty with
>>>>winboard. I think that there is nothing wrong with its book and book
>>>>code. May be, KK has installed the small Crafty book as I did. With the
>>>>default choice for "book random", Crafty only plays lines the frequency
>>>>of which are higher than some threshold value (Bob knows better).
>>>>Apparently, the desired frequencies can hardly be reached in the small
>>>>book. However if you set "book random 5" instead of the default
>>>>randomness for instance, then the threshold is chosen lower and
>>>>variations will be found.
>>>>May be KK has the same effect.
>>>
>>>
>>>I had explained this danger to KK... "small book" means no useful
>>>frequency
>>>data to choose moves.  It is more than possible that the book is so
>>>narrow
>>>that after a few games it has learned that moves are bad.
>>>
>>>This can be verified by adding "show book" to the crafty.rc file, and
>>>then
>>>starting crafty in a dos window (in the right directory) and then trying
>>>the opening moves in question.  It will display *every* book move it
>>>finds,
>>>and will show which are flagged as unplayable "?" due to bad learned
>>>results, no wins, or not played enough to "trust"...
>>
>>What this means then that no matter how large the book is, eventually (
>>it may take a very long time for this to happen) Crafty will not trust
>>any book moves and will think on it's own from the beginning. I don't
>>like this way of learning. Much better would be learning by adding to
>>its book the way that M-chess and 99% of humans do it.
>
>
>not at all, it learns "good" and "bad" stuff...  the problem is
>different.
>If you use a small book, it has no "frequency" data on which to base
>it's
>move selection.  It will *never* play a book move that has no wins, or
>which
>was not played more than once.  So you could have 100,000 positions in
>the
>file, with only a few hundred that were playable...  that's why I never
>recommend the "small" book.  use the 10mb KKUP book.bin and you won't
>have
>any odd book problems...


one thing I forgot.  If you want to play with book learning, please feel
free to do so.  But if you are going to play comet vs crafty and post
the
results, please use a decent book.  Otherwise the match results can be
skewed badly, which sends me off looking for bugs on a wild-goose chase.

use a decent book for public matches, use oddball books for private
matches
and this confusion doesn't happen.



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