The National Center for Health Statistics reports that the mean systolic blood pressure for males 3 to 44 years of age is 128, and the standard deviation in this population is 15. The medical director of a large company looks at the medical records of 72 executives in this age group and finds that the mean systolic blood pressure in this sample is 126.07. Is this evidence that the company's executives have a different mean blood pressure from the general population?
Write out the null and the alternative hypothesis.
What is the appropriate data analysis method for this study?
Calculate the test statistic and effect size.
Make the decision, and explain why.