Re: computer-go: A problem with understanding lookahead

[David Fotland <fotland@xxxxxxxxxxxxxxx>]

A simple example:  A position with a long ladder in it.  I don't know any 
way for a static evaluation function to
predict if the ladder works or not, in general.  But it is very easy to do 
lookahead and find the answer.

At 09:03 PM 1/16/2001 +0100, you wrote:
> Hello all,
>
> I have a serious problem with lookahead. I don't understand why it works. 
> Why should the backed up values of a, say, 7 ply full width alpha-beta 
> minimax search be any better than the values my evaluation function gives 
> me by simply evaluating the positions at ply 1. I can understand that if 
> the end of the game is in sight then lookahead is useful. I can 
> understand  that if I use a quiesence measure or some such and only 
> evaluate positions when I know that my evaluation function will work best 
> then lookahead is useful. But if neither of these is the case then does 
> lookahead help. Is there some way in which the backing up of values and 
> minimaxing somehow reduces the error in the evaluations.
>
> I really am seriously stuck with this one.
>
> Cheers
>
> David
David Fotland