Homework Assignment DUE Saturday 7/24 by 3PM EST
Homework Assignment #8 CNSL 5302
Name: Calculate the variance and standard deviation of the following data. Instructions for hand calculations are given on the second page of this handout. Turn this assignment in inputting the answers into the correct place in Blackboard. Y: 4, 9, 3, 6, 7, 6, 4, 5, 8, 7, 5, 6, 4, 2, 7, 6, 4, 4, 5, 8
Variance and Standard Deviation Hand Calculation
Given the data set Y: 3, 2, 4, 5, 1 1. Place your data in column form. Y 3 2 4 5 1 2. Make a second column called Y
2 and then square each Y.
Y Y
2
3 9 2 4 4 16 5 25 1 1 3. Add (sum) each column. Y Y
2
3 9 2 4 4 16 5 25 1 1 15 55 5. Put the numbers in the formula for variance (s
2 is the symbol for variance).
1
2
2
2
n
y s
n
y
= 15
55 5
15 2
2
s =
4
55 5
225 2
s
4
45552 s =
4
102 s = 5.2
2 s
6. Then calculate the standard deviation (s) by taking the square root of the variance.
2
ss = 5.2s = 58.1s