Refer to Exercise 11.43. a. Conduct a test for lack of fit of the linear regression...

Refer to Exercise 11.43.

a. Conduct a test for lack of fit of the linear regression model.

b. If the model is appropriate, give a 95% prediction band for y.

REFERENCE:

11. 43 : A manufacturer of laundry detergent was interested in testing a new product prior to market release. One area of concern was the relationship between the height of the detergent suds in a washing machine as a function of the amount of detergent added in the wash cycle. For a standard size washing machine tub filled to the full level, the manufacturer made random assignments of amounts of detergent and tested them on the washing machine. The data appear next.

a. Plot the data.

b. Fit a linear regression model.

c. Use a residual plot to investigate possible lack of fit.