Re: computer-go: A problem with understanding lookahead

[William Harold Newman <william.newman@xxxxxxxxxxx>]

On Sat, Jan 20, 2001 at 02:56:52AM +0100, Vincent Diepeveen wrote:
> A queen is 10 points worth in beginners terms.
> 
> That's nearly half of all your pieces.
> 
> In go terms that's equal to start with 150 stones up.

"Start with 150 stones up" would be 150 handicap stones, right? I.e.,
you don't just mean playing a game with 150 points of komi?

I'd have said taking away a queen takes away nearly a third of the
value of your position, measured only in material:
  10 / (10 + 5 + 5 + 3 + 3 + 8 or so) = 10 / (34 or so)

So a comparable score in 19x19 Go is 100 points:
  100 / (361 or so) is about equal to 10 / (34 or so)

But a score of 100 is not comparable to 100 stones, at least not early
in the game. Each early game move is worth on the order of 10 points,
not 1 point. One way of seeing this is that by placing the stones
sufficiently closely, you can control a territory so strongly that the
enemy can't invade. E.g. eight handicap stones on a 9x9 board tends to
make for an 81-point win.

People can quibble about exactly how much a stone is worth, but I'd be
rather surprised to find a player stronger than 10 kyu who didn't
agree that it's more like 10 points than 1 point. I'd say that
removing your opponent's queen is, in pure material terms, more like
starting with 10 stones up.

-- 
William Harold Newman <william.newman@xxxxxxxxxxxxxxxxx>
software consultant
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