[computer-go] How to design the stronger playout policy?

[Yamato]

I guess the current top programs have much better playout policy than
the classical MoGo-style one.

The original policy of MoGo was,

(1) If the last move is an Atari, plays one saving move randomly.
(2) If there are "interesting" moves in the 8 positions around the
    last move, plays one randomly.
(3) If there are the moves capturing stones, plays one randomly.
(4) Plays one random move on the board.

I (and maybe many others) use it with some improvements, however it
will be not enough to catch up the top programs.
Crazy Stone uses a probability distribution of patterns from the
Bradeley-Terry Model. greenpeep uses similar patterns extracted from
the offline self-play.
Then I have tested a lot of change of probability distributions, but
it was very hard to improve the strength.

Any comments?

--
Yamato