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Subject: Re: fail low question

Author: Robert Hyatt

Date: 09:03:48 10/23/97

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On October 23, 1997 at 10:53:29, Chris Whittington wrote:

>
>On October 23, 1997 at 10:41:18, Robert Hyatt wrote:
>
>>On October 23, 1997 at 10:20:58, Chris Whittington wrote:
>>
>>
>>>
>>>The next iteration it does the same thing.
>>>The next iteration the same thing again.
>>>The next iteration it is running out of time, does the same thing again,
>>>but the time controller decides to stop the search after the fai-high
>>>for Ng2+, but before the ensuing fail-low. So, because the search times
>>>out during a critical window, CSTal actually decides to play Ng2+ and
>>>loses of course :(
>>>
>>>
>>>Merde ! as they say in Paris :)
>>>
>>>Chris
>>>
>>
>>this is solvable too.  When time runs out, I *never* bail out of the
>>search until I start to search *another* root move.  I allow a 2X time
>>overflow here in fact, because I handle the case where the first move is
>>good, but the second one is going to be better.  I make sure that
>>whatever
>>root move I am "hung" on when time runs out gets searched to completion
>>to
>>see if it is better, or if it going to fail low.
>
>hmmmm. all very well, but their are times when I've given myself panic
>time and then more panic time and then this happens; there has to be a
>time when you just have to bail out, no ?
>
>Chris

quite possibly.  But adding that "qualification" makes the problem much
less
frequent.  But there's always the case of two moves, where A is better
than
B, but each iteration closes the gap, and the node count for B keeps
going up,
until the last iteration where B will replace A *if* there is enough
time.  I
do my best to allow this...



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