In: Statistics and Probability
BACKGROUND
Starbucks launched its prepaid (debit) Starbucks Card in November 2001. The card, which holds between $5 and $500 can be used at any Starbucks location. Suppose Starbucks management wants to study the reasons why some people purchase debit cards with higher prepaid amounts than do other people. Suppose a study of 25 randomly selected prepaid purchasers is taken. Respondents are asked the amount of the prepaid card, the customer’s age, the number of days per month the customer makes a purchase at Starbucks, the number of cups of coffee that customer drinks per day, and the customer’s income.
DATA
Amount of Prepaid Card ($) | Age | Days per Month at Starbucks | Cups of Coffee per Day | Income ($1,000) |
5 | 25 | 4 | 1 | 20 |
25 | 30 | 12 | 5 | 35 |
10 | 27 | 10 | 4 | 30 |
5 | 42 | 8 | 5 | 30 |
15 | 29 | 11 | 8 | 25 |
50 | 25 | 12 | 5 | 80 |
10 | 50 | 8 | 3 | 30 |
15 | 45 | 6 | 5 | 35 |
15 | 32 | 16 | 7 | 25 |
15 | 23 | 10 | 1 | 20 |
20 | 40 | 18 | 5 | 40 |
35 | 35 | 12 | 3 | 40 |
40 | 28 | 10 | 3 | 50 |
15 | 33 | 12 | 2 | 30 |
200 | 40 | 15 | 5 | 80 |
15 | 37 | 3 | 1 | 30 |
40 | 51 | 10 | 8 | 35 |
5 | 20 | 8 | 4 | 25 |
30 | 26 | 15 | 5 | 35 |
100 | 38 | 19 | 10 | 45 |
30 | 27 | 12 | 3 | 35 |
25 | 29 | 14 | 6 | 35 |
25 | 34 | 10 | 4 | 45 |
50 | 30 | 6 | 3 | 55 |
15 | 22 | 8 | 5 | 30 |
QUESTIONS
(Please put the answers into a "report" style if possible)
1. Using these data, develop a multiple regression model to study how well the amount of the prepaid card can be predicted by the other variables and which variables seem to be more promising in doing the prediction.
2. Rerun your model based on the significant independent variables only and explain the results.
3. What sales implications might be evident from this analysis?