Don Dailey wrote:
This appears to be my exact logic.
That's a good start :)
Also, before we get too deep into this stuff, thanks for your help.
I can imagine many places where you might be doing something wrong.
1. Are you sure you are scoring the final game correctly including
the proper accounting for komi?
I'm pretty sure. Playouts continue until one side has no legal moves
(simple ko, suicides, and eye filling moves are all that remain).
Scoring at that point is exceptionally easy... Stones in atari are dead
and count for the opponent. Spots unfilled by simple ko are scored for
the non-passer (because it can simply fill that spot). The rest is
exceptionally obvious. In play against it and in automated games, it
exhibits the classic MC behavior of winning many games by half a point.
2. Do you include passes in the random games? You should not.
No passes are allowed in the random games. If the random move generator
says to pass it means no legal moves are available and the game gets scored.
3. Are you sure the eye rule isn't somehow broken?
Yeah. An eye point is defined as an empty point where all four
neighbors are the same chain. This prevents weak combos of false eyes,
but does allow it to miss one kind of life.
How do you generate random moves for a game? A simple way, though not
the fastest is build a list of all possible moves, pick one at random
and play
it if it's legal. If it's not, throw the move out and pick randomly
from
the list again. You won't get random moves if you simply start at a
random
position but then just move forward in the list until you find a legal
move.
I implemented the latter after lots of discussion online about the
quality of random move generation method. Out of curiosity, what method
do you use? Do you do the repeated random selection that you describe?
(Likely with moving invalid selections to the end of the list and
picking from the subset)
I've been trying to watch the last several games of my AMAF version on
CGOS to see if it appears to bias near illegal (or eye filling) plays.
I don't see evidence of it. I can rationalize that biased moves would
be selected more frequently by both colors. Maybe I'll have to try
another random move selection strategy, but I suspect it won't create a
difference anywhere near 1000 ELO (the gap between housebot's amaf mode
and anchorman... the best match for the # of sims)
Of course, libego uses the same random number generator and
ego110_allfirst is comparably bad.
4. Do you use a decent random number generator? (probably not an
issue
unless you have a really crappy one.
I use a mersenne twister. It's really good and really fast :)
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