Re: [computer-go] Modern brute force search

[Don Dailey <drd@xxxxxxx>]

The 95% number was completely arbitrary.  A 95% percent score in chess
might mean sccraping  together 1 draw every 10  games.  I don't really
have  a clue  how  good a  world  champion player  is  compared to  an
omnicient player, and  I used 95% as an  arbitrary starting figure.  I
actually  believe the  number to  be more  like 99%  or higher.   

I  do believe  that the  very  best players  might occasionally  draw,
probably more from dumb luck than  anything (by managing not to make a
blunder.)   Please note  that you  can play  random moves  and  have a
statistical chance of drawing against perfect play.  The odds would be
astronomically against such an event occuring, but it is possible.  It
may be that  the very best players can avoid playing  a losing move on
any given turn with a fairly high probability, they would just have to
put a large number of these moves together in the same game.

So assuming chess to be a draw, an omnicient player would never lose a
game, but an incredibly good player might manage an occasional draw.

I think  at this  level, style  is important.  There  are only  3 game
theoretic values in chess, win, loss or draw.  An omnicient player can
play ANY  move that maintains  the best theoretic value  possible.  If
chess is  a draw, it may  be the case  that most of the  opening moves
result in  a drawn  position.  If an  omnicient player  always chooses
it's moves randomly among equal moves (in the game theoretic sense), I
believe a good human might  draw relatively often, since many moves do
not present any  real challenges.  But if an  omnicient players "knew"
something about making it tough on it's fallible human opponent, there
might be very little chance of gatting that occasional draw.

Good chess players know how this work.  I am not a great chess player,
but I once avoided an exchange  or rooks, in what was almost certainly
a  drawn position  against a  much weaker  opponent.  The  exchange of
rooks would have  made the draw simple, and I needed a win. 

In 8x8 checkers,  the top players would often  manage draws against an
omnicient player, but the  omnicient player would never lose.  Chinook
is probably quite close to omnicient with the big endgame databases.

- Don



   X-Original-To: computer-go@xxxxxxxxxxxxxxxxx
   From: Chris Fant <chrisfant@xxxxxxxxxxxxxxxxx>
   Reply-To: Chris Fant <chrisfant@xxxxxxxxxxxxxxxxx>,
	   computer-go <computer-go@xxxxxxxxxxxxxxxxx>
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   > drd@xxxxxxxxxxxxxxxxx wrote:
   > > I don't know how to compare  this gap with GO.  If an omniscient chess
   > > player could win 95% of it's  games against a Bobby Fischer, how would
   > > that compare to "number of stones" in Go?

   Where the heck did 95% come from?  Wasn't the whole idea of an
   omniscient player one that knew perfect play but would try to confuse
   the opponent in hopes of something better than a draw?  But at worst,
   it would draw.  Are you saying that Bobby Fischer was capable of
   perfect play 5% of the time (leading to a draw)?  Surely you are not.
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