EXERCISE 3
PSYCHOLOGICAL MEASUREMENT (806)
SEPTEMBER 8, 1998
DUE SEPTEMBER 22
DIRECTION -- Use the information from the forty subjects and seven variables (Parts I to VII) on the data sheet from Exercise 1 to complete items 1 and 2 and use the attached sheet for the remaining items.
1. Calculate by hand the variance of a composite made up of Parts I and II. Verify by computer.
2. Calculate by hand the variance of a composite made up of Parts I, II, and IV. Verify by computer.
3. Using the attached sheet, calculate by hand the following:
a) The mean and variances of the items and the test.
b) The split-half odd/even reliability of the test.
c) The Coefficient Alpha reliability of the test.
4. Verify the answers in item 3 by computer (see the reliability program in SPSS-X).
5. Explain the relationship between the split-half and the Alpha.
6. Calculate the Analysis of Variance Reliability by computer (see the reliability program). Explain the relationship between the ANOV and Alpha reliability.
Exercise 3:
Person*
|
Items |
A |
B |
C |
D |
E |
F |
G |
H |
|
1 |
0 |
0 |
1 |
0 |
1 |
1 |
1 |
1 |
|
2 |
1 |
1 |
0 |
0 |
1 |
0 |
0 |
1 |
|
3 |
0 |
1 |
1 |
0 |
1 |
1 |
0 |
0 |
|
4 |
0 |
0 |
1 |
1 |
1 |
1 |
1 |
1 |
|
5 |
0 |
0 |
1 |
1 |
1 |
1 |
0 |
0 |
|
6 |
0 |
1 |
1 |
1 |
1 |
0 |
0 |
1 |
|
7 |
1 |
1 |
0 |
0 |
1 |
0 |
0 |
0 |
|
8 |
0 |
0 |
1 |
0 |
0 |
1 |
0 |
1 |
|
9 |
0 |
0 |
1 |
1 |
1 |
1 |
0 |
1 |
|
10 |
0 |
0 |
1 |
0 |
1 |
1 |
1 |
1 |
*Note: 0 = wrong and 1 = right