Consider the following data of 20 students on their highscho
Consider the following data of 20 students on their high-school GPA and undergraduate GPA when they graduated.
Student number
High-school GPA
Undergraduate GPA
1
2.83
3.59
2
3.31
3.11
3
3.50
2.75
4
3.29
3.33
5
3.13
2.84
6
2.81
3.30
7
3.19
3.05
8
3.49
3.28
9
2.93
2.87
10
3.14
3.50
11
3.00
2.72
12
2.95
2.73
13
2.93
3.08
14
2.89
2.81
15
2.76
2.89
16
2.82
3.02
17
3.00
3.27
18
3.13
3.10
19
3.37
2.93
20
3.30
3.07
Use Excel to calculate the correlation between high-school GPA and undergraduate GPA.
Conduct a hypothesis test with the following hypothesis (use alpha value of 0.05):
Null hypothesis: The correlation between high-school GPA and undergraduate GPA is zero.
Alternate hypothesis: The correlation between high-school GPA and undergraduate GPA is not zero.
Answer the following questions:
What is the p-value and how do you interpret it?
What does the alpha value signify?
What is a type-1 error in this case?
What do you conclude as a result of the test?
| Student number | High-school GPA | Undergraduate GPA |
| 1 | 2.83 | 3.59 |
| 2 | 3.31 | 3.11 |
| 3 | 3.50 | 2.75 |
| 4 | 3.29 | 3.33 |
| 5 | 3.13 | 2.84 |
| 6 | 2.81 | 3.30 |
| 7 | 3.19 | 3.05 |
| 8 | 3.49 | 3.28 |
| 9 | 2.93 | 2.87 |
| 10 | 3.14 | 3.50 |
| 11 | 3.00 | 2.72 |
| 12 | 2.95 | 2.73 |
| 13 | 2.93 | 3.08 |
| 14 | 2.89 | 2.81 |
| 15 | 2.76 | 2.89 |
| 16 | 2.82 | 3.02 |
| 17 | 3.00 | 3.27 |
| 18 | 3.13 | 3.10 |
| 19 | 3.37 | 2.93 |
| 20 | 3.30 | 3.07 |
Solution
Correlation Matrix High-school GPA Undergraduate GPA High-school GPA 1.000 Undergraduate GPA .002 1.000 20 sample size

