Over the past decade or so, Starbucks has grown quite rapidly. As they add stores and increase ...

  

Over the past decade or so, Starbucks has grown quite rapidly. As they add stores and increase the number of drinks, their sales revenue increses. In reflecting about this growth, think about some other variables that might be related to the increase in starbucks sales revenues. Some data for the past seven years on the number of starbucks stores (worldwide), approximate sales revenue (in millions), number of different drinks sold, and average weekly earnings of U.S production workers are given here. Most figures are approximate. Develop a multiple regression model to predict sales revenue by the number of drinks sold, number of stores, and average weekly earnings. How strong is the model? What are the key predictions, if any? How might this analysis help Starbucks managment in attempting to determine what drives sales revenues?

  

Sales Year

Revenue

# of   stores

# of   Drinks

Avg weekly   earnings

 

1

400

676

15

386

 

2

700

1015

15

394

 

3

1000

1412

18

407

 

4

1350

1886

22

425

 

5

1650

2135

27

442

 

6

2200

3300

27

457

 

7

2600

4709

30

474