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Subject: Re: Search Instabilities

Author: Daniel Clausen

Date: 07:55:50 01/21/02

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Hi

On January 21, 2002 at 10:41:39, Robert Hyatt wrote:
[snip]
>1.  If you get a fail high at the root on a zero-width window (any move after
>the first move should be searched with a zero-width window) you can't trust it
>unless you re-search it with a bigger beta bound and make _sure_ that it doesn't
>then fail low.  Such fail-high (zero window) fail-low (non-zero window) is an
>artifact of null-move and if you play such a fail high move even if it fails low
>on the re-search, you will die...

Anyone has a trivial example at hand which demonstrates this behaviour?

Why is it that a fail-high with a zero window can't be trusted but a fail-high
with a non-zero window can? Is "non-zero window" enough to be trusted? Or does
it have to be a certain minimum window? I'm sure that as soon as someone posts a
mini-example which shows this behaviour, even I will understand it. :)

Sargon

• Re: Search Instabilities Robert Hyatt 21:46:01 01/21/02
  • Re: Search Instabilities Tony Werten 01:43:30 01/22/02
    • Re: Search Instabilities Robert Hyatt 07:46:40 01/22/02
      • Re: Search Instabilities Tony Werten 22:16:13 01/22/02
        • Re: Search Instabilities Ulrich Tuerke 05:28:40 01/23/02
          • got this wrong Ulrich Tuerke 06:06:05 01/23/02
• Re: Search Instabilities José Carlos 13:11:59 01/21/02
• Re: Search Instabilities Gian-Carlo Pascutto 08:14:55 01/21/02

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