Computer Chess Club Archives


Search

Terms

Messages

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

Author: Robert Hyatt

Date: 18:40:42 06/02/98

Go up one level in this thread


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...



This page took 0 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.