In: Statistics and Probability
A researcher measures the relationship between Internet use (hours per week) and social interaction (hours per week) in a sample of 10 students. The following table lists the hypothetical results of this study.
| Internet Use | Social Interaction |
|---|---|
| X | Y |
| 5 | 5 |
| 9 | 6 |
| 4 | 8 |
| 7 | 7 |
| 11 | 6 |
| 3 | 7 |
| 2 | 3 |
| 6 | 5 |
| 1 | 10 |
| 11 | 4 |
(a) Compute the Pearson correlation coefficient. (Round your
answer to three decimal places.)
(b) Compute the coefficient of determination. (Round your answer to
three decimal places.)
(c) Using a two-tailed test at a 0.05 level of significance, state
the decision to retain or reject the null hypothesis.
Retain the null hypothesis.Reject the null hypothesis.
a) Pearson correlation coefficient (r) :


So correlation coefficient ( r ) is ,


b)
Coefficient of determination = R2 = r^2 = (-0.352)^2 = 0.124
c)
Hypothesis :


Critical value for Person correlation coefficient :
Using Person correlation coefficient table :
Let ,
= 0.05 , n =
10

Critical value for Person correlation coefficient = rc = 0.632
Reject
if the absolute value of r is greater than table value
rc
It is observed that | r | = 0.352 < rc = 0.632
So , Fail to reject null hypothesis.
Conclusion : There is no relationship between Internet use (hours per week) and social interaction