Question

For the following sample of n =8 scores: 0, 1, 1/2, 0, 3, 1/2 , 0, 1

a. Simplify the arithmetic by first multiplying each

score by 2 to obtain a new sample. Then, compute

the mean and standard deviation for the new

sample.

b. Starting with the values you obtained in part a,

make the correction for having multiplied by 2 to

obtain the values for the mean and standard deviation

for the original sample

Answer 1

(a)

The new data set is:

0, 2, 1 , 0, 6, 1 , 0, 2

Following table shows the calculations for mean and SD:

	X	(X-mean)^2
	0	2.25
	2	0.25
	1	0.25
	0	2.25
	6	20.25
	1	0.25
	0	2.25
	2	0.25
Total	12	28

(b)

Since we multiply each number original data set by 2 so to get the mean and standard deviation of old set we neet to divide the mean and SD of bew data set by 2.

The mean of old data set is

The standard deviation of old data set is