Question 1
For the following give:
• Description of the correlation (negative or positive).
• The appropriate critical value for 𝑟 identified from 𝑡-table.
• The comparison of the linear correlation coefficient to that identified in (b).
• Decision on the null hypothesis (H0) and the conclusion based on the
decision.
a) 𝑛 = 10, 𝑟 = 0.149
b) 𝑛 = 60, 𝑟 = −0.765
Question 2
(𝑥) (𝑦)
10 0.39
20 0.79
30 1.19
40 1.61
50 2.03
a) Compute the linear correlation coefficient, 𝑟 and give an interpretation of
the result. (6 marks)
b) Test, using the significance level of 0.05 that there is significant linear
correlation between the time an employee spent at the company and the
employee’s hourly pay. (6 marks)
c) Can 𝑥 be used to predict 𝑦? Give a reason for your answer. (2 marks)
d) If you answered yes to the above, find the equation of the regression line.
(6 marks)
