Post by Timothy ChowPost by MKFor example, would a rollout with 5184 trials
at xg-roller level be as reliable as a rollout
with 2592 tials at xg-roller+ level and as a
rollout with 1296 trials at xg-roller++ level?
There's a subtle distinction between "precision"
and "accuracy."
The distinction is more than subtle, especially
in this context.
Post by Timothy ChowAn "accurate" verdict is one that gives the
correct answer.
That's the loose definition. The strict definition
is "correct and also consistent", i.e. without any
systematic or random errors.
Post by Timothy ChowA "precise" estimate has very little statistical
noise. Increasing the number of trials increases
the precision.
Yes, more trials reduce random errors ("noise")
and give more "consistent" but not necessarily
"correct" results because they don't eliminate
systematic errors.
Post by Timothy ChowIf you have a lot of trials then you can be very
confident that you are learning "what the bot
really thinks" and that it is very unlikely to
change its mind even if you increase the number
of trials to infinity.
This isn't necessarily true and indeed incomplete.
While random errors decrease, systematic errors
may increase (accumulate and compound), thus
cause the bot to change its mind.
And I would say that "precision" may be useful or
even necessary to determine what is "correct" to
begin with, like during the training of bots through
lots of random decisions to figure out the "correct"
ones without already knowing them.
Post by Timothy ChowAccuracy is another matter. Murat of all people
should understand that "what the bot thinks the
correct play is" is not necessarily the same as
"the correct play"; indeed, in some positions, it is
debatable what "the correct play" is since that
can depend on who your opponent is, what their
emotional state is at the time, etc.
It's good that you acknowledge/agree on these
but my arguments go beyond them.
Post by Timothy ChowBut even setting those things aside,
Yes, let's focus on the more tangible...
Post by Timothy Chowsuppose for the sake of argument that we define
"the correct play" as what game theorists would
call an (expectiminimax) "equilibrium" play.
I can only accept "correct play" based on empirical
data (i.e. cubeless equities derived from random
trials), not extrapolated data (i.e. cubeful equities
derived through applying arbitrary formulas to the
empirical data).
Post by Timothy ChowWe can ask whether stronger settings are more
likely to yield the correct play.
I assume you mean look-ahead plies? Can you (or
someone else) expand on this and explain/clarify
how plies work during play and during rollouts?
Post by Timothy ChowThe answer is that we can't ever be completely
sure, but one can give heuristic arguments in
support of this principle. For example, equilibrium
play has a certain self-consistency property,
I won't argue against self-consistency if you can
prove that your equilibrium play is actually that.
Post by Timothy Chowso you can "cross-examine" the bot and see its
answers are self-consistent.
This would be most interesting for me to see. Has
any bot been cross-examined for this and how?
Post by Timothy ChowExperience suggests that stronger settings exhibit
greater self-consistency. Bob Wachtel's book "In
the Game Until the End" has some examples of this.
Can you give some examples here from the book
(under fair use) or from other studies/experiments?
Post by Timothy ChowBut again, the arguments are only heuristic, and
we certainly can't be completely sure in any
particular instance that stronger settings are
giving us more "accurate" answers.
I argue that we can if we have unbiased bots that
are trained not only through cubeless, single-game
play but also through cubeful and "matchful" play,
eliminating extrapolated cubeful/matchful equities.
MK