Answer:
Test statistic = 1.25
Degree of freedom = 3
Explanation:
The following data were obtained from 4 people
Pre-Test Value Post-test Value __ d
43 ________42 _________ 1
28_______ 29 ________ - 1
31 ________30 _________ 1
28 ________ 25 _________ 3
μd = (1 + - 1 + 1 + 3) / 4 = 4 /4 = 1
The mean difference, μd = 1
The standard deviation of difference, Sd = 1.6
The test statistic = μd / (Sd / √n)
Test statistic = 1 / (1.6/2) = 1 / 0.8
Test statistic = 1.25
Degree of freedom, = n - 1 = 4 - 1 = 3