Assignment 4
Do all of this assignment using the in-class handout that I gave you and Excel. You can turn in your handout to me one 2/24, but e-mail your spreadsheet to me before 5 p.m., 2/24/00. The following chart contains the data plotted in the handout.
|
Region |
Population X |
Units Sold Y |
|
1 |
36 |
54 |
|
2 |
26 |
30 |
|
3 |
12 |
28 |
|
4 |
40 |
48 |
|
5 |
24 |
36 |
|
6 |
18 |
30 |
|
7 |
30 |
38 |
|
8 |
30 |
46 |
|
9 |
14 |
16 |
|
10 |
34 |
42 |
Part 1
"Eyeball" Method
1. Draw a line on the in-class handout. Try to draw the line so that the data points are close to the line.
2. Write the equation in Excel for the line you drew.
3. If pop = 38, how many units will be sold? (Use Excel to calculate.)
4. Use Excel to calculate the sum of your squared error terms. (S e2)
5. Use the same spreadsheet to calculate R square.
Part 2
Least Squares
1. Calculate b.
2. Calculate a.
3. Write the equation for the regression line.
4. If pop = 38, how many units will be sold sold?
5. Calculate the sum of your squared error terms. (S e2)
6. Calculate R square.