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Page 81
We can now proceed to determine what value of n will minimize the loss L(n) by taking the derivative of L with respect to n.
C0097-01.gif
where
C0097-02.gif
and
C0097-03.gif
n*,the optimal value of n,satisfies C0097-08.gif, whence we obtain a bound on n* as follows:
C0097-04.gif
or
C0097-05.gif
Noting that C0097-09.gif and that (1 - 2q) rapidly approaches 1 because q decreases exponentially with n, we see that C0097-10.gif where the error rapidly approaches zero as N increases. Thus the observation of the preceding paragraph is verified, the ratio of trials of the observed best to trials of second-best growing exponentially.
Finally, to obtain n* as an explicit function of N, q must be written in terms of n*:
C0097-06.gif
Introducing b = s1/(µ1 - µ2) and N1 = N - n* for simplification, we obtain
C0097-07.gif

 
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