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Subject: Re: About qsearch...

Author: Severi Salminen

Date: 06:45:15 12/28/01

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>if you extend the qsearch too much you may get
>often irrelevant positions that you analyze.
>
>The problem is that one of the players could win the game
>by a move that is not included in the qsearch.
>
>The probability for it increases when
>the number of plies increase and it seems clear
>to me that if you search deep enough the score that
>you have is often not relevant because you can be almost sure
>that the score in the qsearch for one of the previous nodes
>is wrong so you earn less information
>from searching more nodes and at some point common sense
>says that you need to stop because you pay more than you get.

The problem is that you cannot safely terminate qsearch at some arbitary depth.
There is no way to know when the qsearch info is complete or when it isn't.
Qsearch is approximation and that's the way it's supposed to be. Limiting it
will only create problems as you will _allways_ get a really bad score when
limiting it during a capture sequence. And this will give totally wrong results
as opposed to non-limited qsearch. But as soon as I get home I'll test it and
report maybe some results. It is of course true that qsearch doesn't give
totally accurate scores but it really shouldn't as it is selective in its
nature. It's only function is to dynamically resolve the capture sequences in
frontier nodes. It would be equally illogical to limit the number of attackers
in a SEE function. The results would be also very wrong. Think qsearch as
dynamic SEE, well, that's what I do.

Severi



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