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Subject: Re: qSearch and stand pat question

Author: scott farrell

Date: 08:01:53 11/04/03

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On November 04, 2003 at 10:18:48, Mridul Muralidharan wrote:

>Hi,
>
>In this specific position , proper evaluation that an unstoppable pawn duo at
>seventh rank gets a high value should be sufficient.
>But that is not the main problem - this would be the end result of a variation -
>and if this position is not given the sufficient bonus it requires then it could
>have bad instabilities.
>example : even if the white rook is absent - still white is up - but definitely
>by more than atleast 2 pawns here.
>  This is indeed one of the problems that I faced ,and I did mention it in one
>of my previous posts on blind dependence on stand-pat.
>Since I also do "threatening moves" in qsearch - this is indeed an even major
>problem for me.
>I dont have a solution yet - though lot of hacks to get this reduced and in most
>positions , eliminated : (like if previous was a threatening move , then see how
>good the responses are before trying to see whether the standpat should be used
>, etc).

yeh, this is the issue I was trying to get at.

I think we should change its name - something like "blinkered blind stand-pat".

My guess that CM uses something very different. They just extend off of a single
node, and hardly any full width brute force.

>But most of these have to be seriously contained , or they will blow up the
>qsearch.

my experience is: good ideas = exploding trees.

but I am going to keep trying. I am thinking of a specific null-move-qsearch, if
a null-move-qsearch shows huge problems, dont allow stand pat.

Scott

>I hope you have tried out the idea of null-move in qsearch - I found it in the
>CCC archives. Interesting idea - but was just too bad for mess. Maybe it will be
>better for you.
>
>The only decently generic way to eliminate this problem was better evaluation -
>especially due to threats like hung / pinned pieces , king safety , etc.
>But in this position , esp more for position with the modification that i
>mentioned - i think it will be tough to get it right.
>
>
>Regards
>Mridul



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