Re: computer-go: A little Arithmetic

[Andre Engels <engels@xxxxxxxxxx>]

Ran Xiao wrote:

> In your estimation, how many games human has played, good plus not good?

My rough-and-ready estimate would be around 1,000,000,000. But what does it
matter? The number of games that could _possibly_ be played is much and much
larger. If two players go and play a game, independent of who they are and
how strong they are, the chance that the game they play will be one that
has already been played will be extremely small.

> If board configurations can be generalized, there should exit a learning
> system that can generalize these configurations. The real odd balls can be
> dealt by 9K programs. If board configuration can not be generalized, no
> learning scheme will work.

All I intended to say is that the method of working that you suggested
(build an extremely large database of positions, and what to play in those,
and use a simple, weak program for the remaining possibilities) will not
be going to work.

> P.S. I guess Mr. Cho will not like to play a 9K, or sub-standard move. A bad
> move is a bad move.

I would not be saying that too loud. It is a well-known strategy for chess
players to play non-standard openings against computers just to get the
computer out of the opening book fast.

But the better argument still is that the number of positions one would have
to store would be too large. With 10^10 positions in memory, if you would
want to stay within this set of 10^10 positions, if you play deterministic
on each move, your opponent has the choice among an average of 1.2 moves
for each of his (estimated) 125 moves. If we assume that there are 2 moves
at each point that Cho might play, he still has 10^15 possibilities to
play the first 50 moves only, for 125 moves that makes over 10^37. If we
make an estimate of 3 instead, that would make 10^23 and 10^59, respectively.


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Andre Engels, engels@xxxxxxxxxxxxxxxxx
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