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Subject: Re: Fritz won shredder,Century won Boris kogen(2286) in the israeli league

Author: Ed Schröder

Date: 23:59:43 04/02/00

Go up one level in this thread


On April 02, 2000 at 18:41:22, Dave Gomboc wrote:

>On April 02, 2000 at 18:24:06, Ed Schröder wrote:
>
>>On April 02, 2000 at 16:33:24, blass uri wrote:
>>
>>>On April 02, 2000 at 15:46:54, Dave Gomboc wrote:
>>>
>>>>It sounds like your tunable policy paid off, in terms of people discovering good
>>>>adjusted parameters?
>>>>
>>>>Dave
>>>
>>>Chess knowledge=25 is not an idea of me.
>>>
>>>I suggested to use it only after I read in Ed's site that Ed found that it is an
>>>improvement against computers and maybe also an improvement against humans.
>>>
>>>I found also (after I read that Ed found that knowledge=25 is an improvement)
>>>that Rebel(knowledge=0) does not lose in a result of almost 60:0 against
>>>Rebel(chess knowledge=500) at 7 plied depth and it convinced me that Rebel knows
>>>some important things even with knowledge=0.
>>>
>>>I think that the numbers of the chess knowledge parameter were misleading and
>>>the minimal number should be clearly bigger than 0.
>>>
>>>I believe that this is the reason that people did not try to reduce the chess
>>>knowledge parameter in the Rebel century personality contest.
>>>
>>>Uri
>>
>>I also did not expect it either that lowering the Chess Knowledge parameter
>>would make Rebel stronger. In my tests I always increased the value of
>>the Chess Knowledge parameter. When I did a test with [Chess Knowledge=25]
>>(it was just curiosity) I was surprised to see the enormous speed gain of
>>the search. Then [Chess Knowledge=25] suddenly had my full attention.
>>
>>So the improvement was discovered by accident. No real surprise as most
>>of the time it goes that way. Chess remains a mystery, it is like a maze
>>of 2^64 entries and no exit.
>>
>>Ed
>
>That's kind of funny, but I suppose it shouldn't be completely unexpected.  If
>you try increasing the amount of knowledge, and it performs worse, it makes
>sense to try reducing it instead... and there have been other stories of people
>removing knowledge from their programs before.
>
>Dave

It is more complicated than that. The higher one set the [Chess Knowledge]
parameter the better quality of moves the thing will produce. Just play
a 100 games engine-engine match based on a fixed depth time control. The
higher you set the [Chess Knowledge] parameter the bigger the victory.

So the [Chess Knowledge] parameter works and does the job it is supposed
to do. On the other hand a high value of the [Chess Knowledge] parameter
is responsible for loss in speed during the search which may lead to a
loss of a complete (iteration) ply. And losing an iteration ply seems to
be more valuable than the gain of the extra chess knowledge. No doubt this
is true for comp-comp but what if the topic is human-comp? Until now I
really can't tell. So far I have chosen that [Chess Knowledge=25] is also
better against humans. Am I completely sure? No...

Ed



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