Re: computer-go: Evaluating positions

[Heikki Levanto <heikki@xxxxxx>]

On Wed, Jun 20, 2001 at 01:27:03PM -0400, Don Dailey wrote:
> Absolute  ownership   of an
> intersection means that a player is  guaranteed, with best play on his
> part (but not  necessarily the opponents part) to  keep ownership of a
> square without suffering any disadvantage.

There is one even more absolute ownership concept that may come in helpful.
There are points that are mine, and can not be taken away from me even if I
only pass from now on. (eyes of a living group).

> At the beginning of the game, a perfect  player can correctly say that
> he  owns n squares  (n  depends on what  komi should  be to a  perfect
> player) but he cannot  say which squares  they are.  But already, some
> of these squares can be  assigned ownership status.  For instance  the
> first player may  even be able to  claim  base ownership of  the whole
> board (which  just means he can pick  any intersection he wants to and
> have it in his control  at the end of  the game if he is  determined.)
> Most of this ownership goes away as soon as he places the first stone.

This is counter-intuitive. He owns less squares after he plays his stone?


> Does any of this  have a practical use?  

Interesting speculation, but I fear it is more relevant to the mathematical
game of go than to the game we like to play in practice. It may be so that I
can lay claim on one point at the opening, and keep it if I am really
determined, but this sounds like a sure way to loose the game. Thinking in
too absolute terms is bound to lead to inflexible playing. I think the point
when you can start to agree on of who owns what is where the endgame starts.
Earlier than that it all depends...

> "Hot on the attack" does not map very well to anything useful to the
> perfect player.

True, but it does map well to the way humans play the game, and the way we
look at the game, even if it is played between two very imperfect computers.
I guess there will be a while before we can observe perfect players and see
how they actually do it ;-)


  -H

-- 
Heikki Levanto  LSD - Levanto Software Development   <heikki@xxxxxxxxxxxxxxxxx>