Q1) Marketing manager of large supermarket chain would like to use shelf space to forecast sales of pet food. For random sample of 12 similar stores, she collected following information regarding the shelf space, in feet, devoted to pet food and weekly sales in hundreds of dollars.
|
Store
|
1
|
2
|
3
|
4
|
5
|
6
|
|
Shelf Space
|
5
|
5
|
5
|
10
|
10
|
10
|
|
Weekly Sales
|
1.6
|
2.2
|
1.4
|
1.9
|
2.4
|
2.6
|
|
Store
|
7
|
8
|
9
|
10
|
11
|
12
|
|
Shelf Space
|
15
|
15
|
15
|
20
|
20
|
20
|
|
Weekly Sales
|
2.3
|
2.7
|
2.8
|
2.6
|
2.9
|
3.1
|
a) What is the equation for least squares line?
i) = 2.63 + 0.724x
ii) = 1.45 + 0.724x
iii) = 1.45 + 0.074x
iv) = 2.63 - 0.174x
b) Calculate the coefficient of determination.
i) 0.8270
ii) 0.6839
iii) 0.3081
iv) 0.0009
c) Create a 95% prediction interval estimate for weekly sales, in hundreds of dollars, for a store with 8 feet of shelf space devoted to pet food.
i) 2.86 < y < 6.23
ii) 1.31 < y < 2.77
iii) -0.131 < y < 1.84
iv) 1.54 < y < 4.24