A human resources specialist has compiled annual numbers of person-days of work lost, due to work stoppages, in the water-based transportation industry. These are the results (based on data from Human Resources Canada, Workplace Information Directorate):
n = 40 = 38,015.7 median = 18,240.0 s = 49,288.8
a. Construct a 96% confidence interval estimate for the population mean of annual numbers of person-days lost.
b. Why can we not use the methods of Section 6-5 to construct confidence interval estimates of the population standard deviation?