Subject: Alpha-Beta abolished

From: [email-masked] (Ulrich Mayring)
Date: Wed, 28 Apr 93 21:47:20 MET DST

Hi folks

What do you think of the following (theoretical and impractical) idea:
Abolish Alpha-Beta Pruning and instead store the complete tree for depth n
in RAM or on disk somewhere. Once the computation for depth n is carried out
the best move according to Minimax is carried out. The next n/2-1 moves can
be carried out without any kind of computation, since you only have to look in
the stored proof tree.

Now, if you made your program compute a tree of depth 150 (impossible, I know),
you would be able to play a whole game without any delay waiting for the
computer's moves :-)

Anyways, the question I ask myself: Is there any depth of the search-tree, where
this strategy is time-efficient, enough RAM being available for the sake of the
argument.

Joking (?!?),

Ulrich.

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From: [email-masked]
Date: Thu, 29 Apr 93 08:35:48 +0200

>be carried out without any kind of computation, since you only have to look in

Not good, because the closer you get to the leafs the worse your minimax
value gets. If you can expand the whole search tree then you actually
solved the game (as has been done with connect-four) and store this tree
once and can always play ideally. Reusing older trees to improve
move-ordering is however a widely used technique.

Cheers
	- ant