Question

QUESTION 1 Tamiflu is a drug used to treat influenza. A study found that Tamiflu reduced symptom duration an average of 0.85 days in otherwise healthy (i.e., not high risk) individuals. The researchers reported a 95% confidence interval for the reduction in symptom duration of 0.3 to 1.4 days. Which is a correct interpretation of this result? Choose all that apply.

A. There is a 95% chance that the true mean reduction in symptom duration is between 0.3 and 1.4 days.

B. 95% of all influenza patients will have a reduction of symptom duration between 0.3 and 1.4 days if they take Tamiflu.

C. The method used to produce the interval 0.3 to 1.4 days gives an interval that contains the true mean 95% of the time.

D. 95% of the symptoms will disappear within 0.3 to 1.4 days when taking Tamiflu.

E. The margin of error in the estimate is 0.55 days, with 95% confidence.

QUESTION 2 Agricultural researchers studied a feed supplement for cattle and found that the cows in their study gained an average of 56 pounds. They reported a margin of error of 11 pounds with 95% confidence. Which of the following is/are correct interpretation(s) of this result?

A. 95% of the cows in the study gained between 45 and 67 pounds

B. We’re 95% sure that a cow fed this supplement will gain between 45 and 67 pounds

C. The average weight gain of cows fed this supplement will be between 45 and 67 pounds 95% of the time

D. There is a 95% chance that the mean weight gain of all cows fed this supplement is between 45 and 67 pounds

E. We are confident that the mean weight gain of all cows fed this supplement is between 45 and 67 pounds because 95% of the time, an interval constructed in this way will contain the true mean.

Answer 1

Correct interpretation are as follows:

1)

A. There is a 95% chance that the true mean reduction in symptom duration is between 0.3 and 1.4 days.

2)

mean +/- ME

56 +/- 11 = 45 and 67

D. There is a 95% chance that the mean weight gain of all cows fed this supplement is between 45 and 67 pounds