Re: computer-go: unmake move?

[Tristan Cazenave <cazenave@xxxxxxxxxxxxxxxxx>]

Don Dailey wrote:

> > String tactics is fast since the evaluation is just the
> > number of liberties.  Stable is 5 liberties, and captured is
> > zero.
>
> I do this too, but I don't do it very well.  I'm  not sure which moves
> to cover.  I consider all moves to the  liberties of the target string
> and have some simple stopping rules to  try to control  the search.  I
> include some  moves that attack the  opponent if it's  relevant to the
> target string.  I can  find ladders and the  thing does work, sort of.

> Is there a good description of how this might be done somewhere?  I am
> sure I don't have it right.

You may find this paper interesting:

http://www.ai.univ-paris8.fr/~cazenave/APS.ps

During a dinner at 99'Ing cup in London, we had a discussion
about that, I remember people believing that the number of
liberties is a good indicator of the 'capturability' of a string.
I did not think so, but could not find good arguments.
Here they are. Any comments welcome.

--
Tristan Cazenave
Universite Paris 8, Departement Informatique, Labo IA
2, rue de la Liberte 93526 Saint-Denis Cedex - France
http://www.ai.univ-paris8.fr/~cazenave/