In April 1996, The Globe and Mail listed the salaries of the hundreds of University of Toronto staff who earn at least $100,000 annually. On studying this article, several disgruntled staff (whose last names begin with S, V, and Q) concluded that top staff whose names begin with S to Z earn less than their counterparts.
a. Based on the sample data shown, construct appropriate null and alternate hypotheses, and test the employees' claim, at the 0.05 significance level. Mean salaries are in $1000s.
b. Construct a 95% confidence interval for - where ttj is the mean salary of the reported staff with last names starting with the letters A to R. Do the confidence interval limits contain 0? Does this indicate that there is or is not a significant difference between the two means?