In: Statistics and Probability
The manufacturer of a type of exercise equipment wants to study the relationship between the number of months (Months) since the type of equipment was purchased and the length of time (Hours) the equipment was used last week. The data is below. Person Fred Bob Joe Tina Lisa Jen Karl Hank Leah Anna Months 12 2 6 9 7 2 8 4 10 5 Hours 4 10 8 5 5 8 3 8 2 5
Following the style of the worksheet illustrated in Table 12.2 in your textbook, use the data provided above and create an analogous worksheet. Computer Deliverable d. Using the answers developed in the worksheet, what is the estimated regression equation? Use the labels Months and Hours appropriately in your equation. e. Predict the number of hours of usage for someone who bought the equipment 8 months ago? (4 pts) f. If there is a person who bought the equipment 8 months ago, what is the residual for that particular person?
x | y | x-xbar | y-ybar | (x-xbar)(y-ybar) | (x-xbar)^2 | |
12 | 4 | 5.5 | -1.8 | -9.9 | 30.25 | |
2 | 10 | -4.5 | 4.2 | -18.9 | 20.25 | |
6 | 8 | -0.5 | 2.2 | -1.1 | 0.25 | |
9 | 5 | 2.5 | -0.8 | -2 | 6.25 | |
7 | 5 | 0.5 | -0.8 | -0.4 | 0.25 | |
2 | 8 | -4.5 | 2.2 | -9.9 | 20.25 | |
8 | 3 | 1.5 | -2.8 | -4.2 | 2.25 | |
4 | 8 | -2.5 | 2.2 | -5.5 | 6.25 | |
10 | 2 | 3.5 | -3.8 | -13.3 | 12.25 | |
5 | 5 | -1.5 | -0.8 | 1.2 | 2.25 | |
65 | 58 | 0 | 0 | -64 | 100.5 | |
6.5 | 5.8 | |||||
mean xbar | ybar | SS_xy | SS_xx | |||
xbar and ybar are average .
e)
SUMMARY OUTPUT | |||||
Regression Statistics | |||||
Multiple R | 0.826939645 | ||||
R Square | 0.683829176 | ||||
Adjusted R Square | 0.644307823 | ||||
Standard Error | 1.534754911 | ||||
Observations | 10 | ||||
ANOVA | |||||
df | SS | MS | F | Significance F | |
Regression | 1 | 40.75622 | 40.75622 | 17.30278 | 0.003167 |
Residual | 8 | 18.84378 | 2.355473 | ||
Total | 9 | 59.6 | |||
Coefficients | Standard Error | t Stat | P-value | Lower 95% | |
Intercept | 9.939303483 | 1.107151 | 8.97737 | 1.89E-05 | 7.386209 |
months | -0.63681592 | 0.153093 | -4.15966 | 0.003167 | -0.98985 |
y^ = 9.9393 - 0.6368* months
f)
y^ = 9.9393 - 0.6368 * 8
= 4.8449
residual = yi - y^
= 4 - 4.8449
= -0.8449