# Question: A manager of boiler drums wants to use regression analysis

A manager of boiler drums wants to use regression analysis to predict the number of worker-hours needed to erect the drums in future projects. Data for 36 randomly selected boilers have been collected. In addition to worker-hours (Y), the variables measured include boiler capacity, boiler design pressure, boiler type, and drum type. All of these measurements are listed in the file P10_27.xlsx.

a. Estimate an appropriate multiple regression equation to predict the number of worker-hours needed to erect boiler drums.

b. Interpret the estimated regression coefficients.

c. According to the estimated regression equation, what is the difference between the mean number of worker-hours required for erecting industrial and utility field boilers?

d. According to the estimated regression equation, what is the difference between the mean number of worker-hours required for erecting boilers with steam drums and those with mud drums?

e. Given the estimated regression equation, predict the number of worker-hours needed to erect a utility-field, steam-drum boiler with a capacity of 550,000 pounds per hour and a design pressure of 1400 pounds per square inch. How accurate is your prediction?

f. Given the estimated regression equation, predict the number of worker-hours needed to erect an industrial-field, mud-drum boiler with a capacity of 100,000 pounds per hour and a design pressure of 1000 pounds per square inch. How accurate is your prediction?

a. Estimate an appropriate multiple regression equation to predict the number of worker-hours needed to erect boiler drums.

b. Interpret the estimated regression coefficients.

c. According to the estimated regression equation, what is the difference between the mean number of worker-hours required for erecting industrial and utility field boilers?

d. According to the estimated regression equation, what is the difference between the mean number of worker-hours required for erecting boilers with steam drums and those with mud drums?

e. Given the estimated regression equation, predict the number of worker-hours needed to erect a utility-field, steam-drum boiler with a capacity of 550,000 pounds per hour and a design pressure of 1400 pounds per square inch. How accurate is your prediction?

f. Given the estimated regression equation, predict the number of worker-hours needed to erect an industrial-field, mud-drum boiler with a capacity of 100,000 pounds per hour and a design pressure of 1000 pounds per square inch. How accurate is your prediction?

## Answer to relevant Questions

Suppose that a regional express delivery service company wants to estimate the cost of shipping a package (Y) as a function of cargo type, where cargo type includes the following possibilities: fragile, semi fragile, and ...The human resources manager of DataCom, Inc., wants to predict the annual salaries of given employees using the potential explanatory variables in the file P10_05.xlsx.a. Estimate an appropriate multiple regression equation ...A power company located in southern Alabama wants to predict the peak power load (i.e., the maximum amount of power that must be generated each day to meet demand) as a function of the daily high temperature (X). A random ...The file P10_48.xlsx contains monthly sales and price of a popular candy bar.a. Describe the type of relationship between price and sales (linear/nonlinear, strong/weak).b. What percentage of variation in monthly sales is ...We stated in the beginning of the chapter that regression can be used to understand the way the world works. That is, you can look at the regression coefficients (their signs and magnitudes) to see the effects of the ...Post your question