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提问人：网友zhanxiong883
发布时间：2022-01-07
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A random experiment has seven outcomes with probabilities 1／3，1／3，1／9，1／9，1／27，1／27，1／27．T
he experiment is to be performed once and the outcome transmitted across the country．The telegraph company provides two services．Service 1 transmits binary digits at $2．00 per digit．Service 2 transmits ternary digits at $3．25 per digit．You are to select a service and design a code to minimize expected cost． (1)Which service should be selected？ (2)What code should be used？ (3)What iS the expected cost？ (4)If the ternary cost is changed，at what value of new cost would be change your mind？ (5)Suppose the experiment is to be repeated a large number of times．How do the above answers change？
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uses the estimated standard error? b. Find the 95% “Wald confidence interval” for π. Is it believable? (When the observation falls at the boundary of the sample space, often Wald methods do not provide sensible answers.) c. Conduct the “score test,” for which
uses the null standard error. Report the P-value. d. Verify that the 95% score confidence interval (i.e., the set of π0 for which |z|< 1.96 in the score test) equals (0.0,0.133). (Hint: What do the z test statistic and P-value equal when you test H0:π =0.133 against Ha:π = 0.133.)
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