In: Statistics and Probability
The marketing manager of a large super-market chain has the business objective of using shelf space most efficiently. Toward that goal, they would like to use shelf space to predict the sales of a specialty pet food. Data are collected from a random sample of 12 equal-sized store, with the following results: Shelf Space Sales Aisle Location 5 160 0 5 220 1 5 140 0 10 190 0 10 240 0 10 260 1 15 230 0 15 270 0 15 280 1 20 260 0 20 290 0 20 310 1 For these data, Syx = 30.8058436 and hi = 0.1373333 when X = 8. *Round final answers below to three decimal places. Do not round calculations until the final answer.
(a) Construct a 95% confidence interval estimate of the mean weekly sales for all stores that have 8 square feet of shelf space for pet food.
(b) Construct a 95% prediction interval of the weekly sales of an individual store that has 8 square feet of shelf space for pet food.
(c) Explain the difference in the results of (a) and (b).