40. In Example 7.30, we started with U  I(X1  0) and used a conditional expectation argument to obtain an unbiased estimator of the zero-defect probability based on the suf cient statistic. Consider starting with a different statistic: .

Show that the improved estimator based on the suf cient statistic is identical to the one obtained in the cited example. [Hint: Use the general property

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