In: Statistics and Probability
The owner of a moving company typically has his most experienced manager predict the total number of labor hours that will be required to complete an upcoming move. This approach has proved useful in the past, but the owner has the business objective of developing a more accurate method of predicting labor hours. In a preliminary effort to provide a more accurate method, the owner has decided to use the number of cubic feet moved as the independent variable and has collected data for 36 moves in which the origin and destination were within the borough of Manhattan in New York City and in which the travel time was an insignificant portion of the hours worked.
A | B | C | D | |
1 | Hours | Feet | Large | Elevator |
2 | 24 | 545 | 3 | yes |
3 | 13.5 | 400 | 2 | yes |
4 | 26.25 | 562 | 2 | no |
5 | 25 | 540 | 2 | no |
6 | 9 | 220 | 1 | yes |
7 | 20 | 344 | 3 | yes |
8 | 22 | 569 | 2 | yes |
9 | 11.25 | 340 | 1 | yes |
10 | 50 | 900 | 6 | yes |
11 | 12 | 285 | 1 | yes |
12 | 38.75 | 865 | 4 | yes |
13 | 40 | 831 | 4 | yes |
14 | 19.5 | 344 | 3 | yes |
15 | 18 | 360 | 2 | yes |
16 | 28 | 750 | 3 | yes |
17 | 27 | 650 | 2 | yes |
18 | 21 | 415 | 2 | no |
19 | 15 | 275 | 2 | yes |
20 | 25 | 557 | 2 | yes |
21 | 45 | 1028 | 5 | yes |
22 | 29 | 793 | 4 | yes |
23 | 21 | 523 | 3 | yes |
24 | 22 | 564 | 3 | yes |
25 | 16.5 | 312 | 2 | yes |
26 | 37 | 575 | 3 | no |
27 | 32 | 600 | 3 | no |
28 | 34 | 796 | 3 | yes |
29 | 25 | 577 | 3 | yes |
30 | 31 | 500 | 4 | yes |
31 | 24 | 695 | 3 | yes |
32 | 40 | 1054 | 4 | yes |
33 | 27 | 486 | 3 | yes |
34 | 18 | 442 | 2 | yes |
35 | 62.5 | 1249 | 5 | no |
36 | 53.75 | 995 | 6 | yes |
37 | 79.5 | 1397 | 7 | no |
A) Construct a scatter plot.
B) Assuming a linear relationship, use the least-squares method to determine the regression coefficients b0 and b1.
C) Interpret the meaning of the slope, b1, in this problem.
D) Predict the mean labor hours for moving 500 cubic feet.
E) What should you tell the owner of the moving company about the relationship between cubic feet moved and labor hours?
Please show all work in detail.
The answers are obtained using R-software. Code and output are attached below along with the graph.