... be repeated at will, in many other cases this is, indeed, the case. In the latter case, as a rule, it is advantageous not to fix the sample size in advance, but to keep sampling and terminate the ... (as well as in the interval estimation problemsto be dealt with in Chapter 15), sampling according to a stopping time is, in general, profitable, the mathematical machinery involved is well beyond ... Zn alone.REMARK 1 In certain circumstances, a stopping time N is also allowed totake the value ∞ but with probability equal to zero. In such a case and whenforming EN, the term ∞ · 0 appears,...