[computer-go] Explanation to MoGo paper wanted.

[Jacques Basaldúa]

Hi, Magnus

Magnus Persson wrote:

>Weak tactics is a problem of the playouts in my opinion. 
>UCT as a general search method has thus little to do with 
>ladders and other game specific details. If there are no 
>tactical mistakes in the playouts the problems disappear. 
>Also tactics has a large impact on where territory appears 
>in the playout, since much of the noise in the playouts come 
>from tactical mistakes near the end of the game.

I was meaning the specific problems already mentioned in this 
list where you should not start something (e.g. a ladder)
unless you a sure to win. The more you play (if you don't win)
the more you lose. The best move is "hidden" by the increasingly
negative evaluation of continuing the ladder another step and
losing it. In a 9x9 board, ladders may no be very long, but in
19x19 they can. Of course, in the case of ladders that has simple
solutions as forcing the playout to follow the atari-lines, but 
in more complex situations there is no known (to me) solution.
Of course, UCT would find the optimal solution with infinite 
time, but that is not the question. In fact, it is harder
to find the solution with UCT than with non stochastic methods.


Jacques.