Independent Student t
Item #1
Calculate am independent t-test for the following data:
X1 X2
6 12
4 4
2 7
3 10
9 5
6 8
5 3
Mean of group 1 _____
Mean of group 2 _____
Difference between the means _____
SS of group 1 _____
SS of group 2 _____
n(n-1) _____
t = _____
How many degrees of freedom (df) at in this study_____
What is the critical value for t (2 tailed, .05 alpha) _____
Is the t significant _____
Item #2
Calculate am independent t-test for the following data:
X1 X2
15 3
11 5
8 4
12 2
7 6
Mean of group 1 _____
Mean of group 2 _____
SS of X1 _____
SS of X2 _____
t = _____
Item #3
Calculate am independen t-test for the following data:
X1 X2
6 3
7 5
6 3
8 2
4 7
11 4
t = _____
How many degrees of freedom (df) at in this study ____
What is the critical value for t (2 tailed, .05 alpha) _____
Is the t significant? _____
Item #4
Which students do significantly better in reading (Words per minute):
High Sch College
7 5
4 3
6 1
6 11
3 8
2 8
1 13
6 9
t =
.
Item #5
Which cars are the safest (accidents):
Foreign Domestic
16 1
14 3
12 9
18 11
12 6
7 1
t =
Item #6
Which dogs are the meanest (bites per minute):
Big Little
1 6
4 3
3 9
8 11
2 16
7 11
5 22
3 7
t =
ANSWERS
Item #1
Calculate am independent t-test for the following data:
X1 X2
6 12
4 4
2 7
3 10
9 5
6 8
5 3
Mean of group 1 5
Mean of group 2 7
Difference between the means 2
SS of group 1 32
SS of group 2 64
n(n-1) 42
t = 1.32
How many degrees of freedom (df) at in this study N-2 = 12
What is the critical value for t (2 tailed, .05 alpha) 2.18
Is the t significant No. The calculated value (1.32) is not equal to (or bigger) that the critical value (2.18). The differences between the groups is likely to be due to chance.
Item #2
Calculate am independent t-test for the following data:
X1 X2
15 3
11 5
8 4
12 2
7 6
Mean of group 1 10.60
Mean of group 2 4.00
SS of X1 41.20
SS of X2 10
t = 4.13
Item #3
Calculate am independen t-test for the following data:
X1 X2
6 3
7 5
6 3
8 2
4 7
11 4
t = 2.48
How many degrees of freedom (df) at in this study 10
What is the critical value for t (2 tailed, .05 alpha) 2.23
Is the t significant? Yes
Item #4
7 5
4 3
6 1
6 11
3 8
2 8
1 13
6 9
Item #5
16 1
14 3
12 9
18 11
12 6
7 1
Item #6
1 6
4 3
3 9
8 11
2 16
7 11
5 22
3 7
