Hello Jason

I think what you are trying to do can be done more easily.

A. You have a Bernoulli random variable whose result is 0 or 1
following an unknown probability p. (Excuse me for explaining
obvious things, this is for anyone who reads it.) You want to
estimate p from a random sample. The estimator of p computed
from the sample is usually called p-hat (a "^" char on a "p")
Of course, the same board position produces 0 or 1 with the
same probability p.

B. You cont the number of wins. Therefore, you have a
random variable which follows a BINOMIAL (n, p) being
n the sample size.

C. To compare if a move is better than another, you have
to compare _confidence intervals_. I.e. the interval in which
p (the unknown probability) lies computed from your
observed p-hat, n and a desired confidence level, say 95%.
These intervals can be computed with methods you can
find searching for "Confidence Interval for a Binomial
Proportion". The most used are Wilson and Agresti-Coull
intervals. These intervals include continuity correction
as you mention in your post. Other ways of comparing
proportions are: The difference between proportions, the
relative risk and the odds ratio to name a few. My "Bible"
for this is a book called "Categorical Data Analysis" from
Alan Agresti published by Wiley & Sons.

> To use these results, you must make some assumption
> about the underlying distribution of a move's probability
> of winning.

That's the good news. You don't. There is no need to
understand what complex mechanism produces p. Only
that: same position == same p.

*Do not* expect a sound statistical analysis to tell you
the best move, unless it is very obvious, n is immense or
your confidence level is extremely low. But, if you are
lucky, it will tell you what moves are clearly bad and can
be safely (= with a given confidence) pruned out.

Computing distributions is not as hard as it may seem
because you can interpolate from a LUT with reasonable
precision. Anyway, even if I have the statistical skills
to do that, I personally am not doing things "that well"
because I believe computing time is more productive
doing more simulations than "quality control". I may
be wrong.

Jacques.
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