How do you handle n_i = 0 in equation 1.2?  I'd assume that if a heuristic
says a move is really bad (H_B = 0), then you'd want to avoid simulations
for a while.

Also, has mango experimented with other related strategies for a soft
transition?

In my own mathematical recreation, I came up with a slightly variant method.
Just to keep the text short, here's the notation that I'll use...
 N = number of simulations through parent node
 n_i = number of simulations through this node
 w_i = winning simulations through this node
 v_i = w_i / n_i
 H_B = heuristic_bias
 n_h = heuristic confidence (used in my equation)
 UCTdelta = sqrt(ln(N)/n_i)
 p_hat = estimated probability of winning with soft transition

... then equation 1.2 is p_hat + UCTdelta

For you,
 p_hat = (w_i + H_B)/n_i
I derived and posted the following formula to the list:
 p_hat = (w_i + n_h*H_B)/(n_i+n_h)

The two equations are fairly similar... especially if n_h is set to 1.  Then
the only difference is that I replace n_i with (n_i+1)... and allows p_hat
to be calculated with n_i = 0.  I made no attempt to handle UCTdelta, but
replacing n_i in there with n_i+n_h is probably reasonable

On 5/17/07, Chaslot G (MICC) <[EMAIL PROTECTED]> wrote:

 Dear all,


Following the example of RĂ©mi, I would like to share with you a paper that
I wrote which describe some important elements of my Go program Mango.

I submitted this paper recently to the JCIS workshop 2007. Due to the fact
that it was an extended abstract, a lot of details are missing. I am now
working on the full paper, which will contain much more information.



The extended abstract can be found here:
www.cs.unimaas.nl/g.chaslot/papers/pMCTS.pdf



Cheers,



Guillaume



PS: To answer's Sylvain question: Modifying the probability distribution
of moves in the tree was more effective in Mango than the improvement done
on the simulation strategy. However, Mango simulation strategy is not as
good as CrazyStone's or Mogo's one. So I guess Mango won against Mogo in the
last KGS tournament because it had a better way to use domain knowledge in
the Tree.

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