Question 13.45

13.45 Warehouse club and superstore sales.

Consider the warehouse club and superstore sales series discussed in Examples 13.15 and 13.16 (pages 671–674).

club

  1. Make scatterplot of sales versus (a lag of 12 periods). What does the scatterplot suggest?
  2. What is the correlation between and ?
  3. How well do sales 12 months ago appear to predict this month’s sales? Explain your response.

13.45

(a) Sales is linearly related to lag12sales. (b) . (c) . There is a significant linear relationship between this month’s sales and sales 12 months ago.