Re: Shallow Or Deep Search?

["P.J.Leonard" <P.J.Leonard@xxxxxxxxxx>]

Darren Cook wrote:
> 
> >1) Results from searches that are not "deep enough" give results of
> >such poor quality, that they are tantamount to worthless.
> 
> I agree with this.** You must search until you find something. **
> Otherwise you are just wasting processor time.
> 
> 'something' means an answer one way or the other to the question you gave to
> your search.
> 
> If the question was "can this group live?" then you search until the group
> is provably alive or dead.

 The problem with this is many positions can not be searched to the 
bitter end. At the start of your search your goal may be prove
life/death.
However after you find that a tree with the reasonable moves starts
getting
too wide you need to switch your goal posts. Your absolute life and
death evaluation
needs to be replaced by a heuristic evaluation that estimate things like
"can this
string escape into the middle and connect".  There is also a case for
examining the 
heuristic evaluations before embarking on a search. 
We humans are very good at mixing this type of heuristic thinking with
analysis.

 
  cheers Paul.