Re: computer-go: [Question] Alpha-Beta Pruning & Null Move

[heikki@xxxxxx]

On Thu, Apr 12, 2001 at 09:35:07AM -0700, Xu, Mousheng  (SEA) wrote:
> I just don't see how alpha-beta pruning can save mentionable calculation.

In computer context, you can explain it by considering a life and death
problem. If you find a move that kills, that is enough, and you can skip all
the other moves in that position. Of course you need to check all replies to
this, to be sure it really kills. Likewise, if (in another branch) you find
a move that gives life, you do not need to check alternative moves. Again,
to be sure it lives, you need to check all responses to it.

The same thinking applies to more detailed situations, where you try to find
the most valuable move. In that case you do need some sort of bounds for
what you think you can find in any subtree. If you have no such estimates,
alpha-beta won't give you anything much.

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