In: Statistics and Probability
1) The Payroll data set has data on the numbers of employees and the monthly payroll in thousands of dollars for 50 firms in two different industries. If you divide ”payroll” by ”employees” you get the average monthly salary for each firm. The populations of interest are the firms in industry A and those in industry B. The population variable of interest is the average monthly salary in each of the firms of these populations. At a significance level of α = 0.05 test the null hypothesis that the means of by-firm average monthly salaries in industries A and B are equal. 4.
2) Construct side-by-side boxplots of average monthly salaries per firm in industries A and B. Critique your answer in problem 3.