In Problem 13.4 on page 531 concerning pet food sales, the marketing manager used shelf space for

Question:

In Problem 13.4 on page 531 concerning pet food sales, the marketing manager used shelf space for pet food to predict weekly sales.
a. Is it necessary to compute the Durbin-Watson statistic in this case? Explain.
b. Under what circumstances is it necessary to compute the Durbin-Watson statistic before proceeding with the least-squares method of regression analysis?