REPOSTING THIS QUESTION AS PREVIOUS ANSWERS WERE WRONGINCOMP

REPOSTING THIS QUESTION AS PREVIOUS ANSWERS WERE WRONG/INCOMPLETE:

The National Center for Health Statistics reports that the mean systolic blood pressure for males 35 to 44 years of age is 128. The medical director of a company looks at the medical records of 64 company executives in this age group and finds that the mean systolic blood pressure in the sample is x = 126.07 and the sample standard deviation s = 16.

The hypotheses are

H₀: = 128

H_a: 128

where is the mean systolic blood pressure of male executives 35 to 44 years of age.

At the = .05 significance level, the null hypothesis H₀: = 128 is not rejected (verify this).

Question 1. Would a 95% confidence interval contain the value 128? (Do not calculate the confidence interval to answer this question). Yes or No?

The company medical director now worries if the hypothesis test would detect an important difference if one were present,so she is concerned about power. Power calculations for t tests are very complicated. However, we can obtain very good approximations using z (the standard normal) in place of t.

Question 2. Find the power of the test against the alternative = 130

Question 3. Find the power of the test against the alternative = 125

Solution