[computer-go] Interesting problem

[Aloril]

On Thu, 2006-12-28 at 11:53 +0100, alain Baeckeroot wrote:
> Le jeudi 28 décembre 2006 03:34, Don Dailey a écrit :
> > I'm having an interesting problem - my hope is to set
> > a random legal move making player (who doesn't fill
> > 1 point eyes) at ELO zero.     
> Hmm maybe i misunderstand. It seems to me that a random player
> cannot have a fixed rating  (except -infinity) as it will lose
> all his games against non random player. 

First thing: Don Dailey is talking about equivalent player to
PythonBrown in 9x9 CGOS, not Random.

However, for remainder of mail I'm talking mainly about actual random
player. I think it has finite, albeit negative rank at 9x9 CGOS.

Random statistics against PythonBrown:
Result: 348/2511
Win:       13.9%

It manages enough often to pass in position where weak opponent has
passed and its winning ;-)

On 19x19 I think win % would be significantly lower.

> Or if it is set at zero ELO all other non random bot will slowly
> drift toward +infinity.

Actually given *enough* games "fully random including eye filling and
passing moves" will win against a pro player. I did find one game where
pseudorandom player (==Random at CGOS) wins against GNU Go on 5x5 board.
Haven't found one in 7x7 though.

I don't know about if this holds true for "non eye filling random
player", sometimes it's impossible for it to randomly to play best
move ;-)

-- 
Aloril <aloril at iki.fi>