In: Statistics and Probability
The Bureau of Labor Statistics shows that the average insurance
cost to a company per hour worked for an employee by major industry
group, is $2.94 for construction workers and $3.76 for
manufacturing workers. Suppose these figures were obtained from 14
construction workers and 15 manufacturing workers and that their
respective population standard deviations are $1.38 and $1.51.
Assume that such insurance costs are normally distributed in the
population.
Calculate a 98% confidence interval to estimate the difference in
the mean hourly company expenditures for insurance for these two
groups. What is the value of the point estimate?Test to determine
whether there is a significant difference in the hourly rates
employers pay for insurance between construction workers and
manufacturing workers. Use a 2% level of significance.