Question

Calculate d and sd for the paired data given below. Assume the two samples are dependent samples of paired data, and assume the population distribution of the paired differences are approximately normal. Don’t round. (1 point)

Group A	18	23	24	19	17	22	18	16	20
Group B	24	23	23	19	20	21	23	19	23

Answer 1

Solution:

Before	after	d	d2
18	24	-6	36
23	23	0	0
24	23	1	1
19	19	0	0
17	20	-3	9
22	21	1	1
18	23	-5	25
16	19	-3	9
20	23	-3	9
		SUM = -18	Sum = 90

Now ,

= (Sum of d )/ n = -18/9 = -2

Now ,

Let s_d be the standard deviation of d

Sample variance s² =

= [1/(9 - 1)][90- ((-18)²/9) ]

= 6.75

Now , standard deviation = = 2.59807621135

s_d =  2.59807621135

Answer :

= -2

s_d =  2.59807621135