Module 5 examples
- Sample Data
|
1.3, 1.2, 1.2, 1.1,
1.5, 1.4, 1.3, 1.2, 1.2, 1.5, 1.4, 1.3 |
1.3 + 1.2 + 1.2 + 1.1 + 1.5 + 1.4 + 1.3 + 1.2 + 1.2 + 1.5 + 1.4 + 1.3 = 15.6
Mean = 15.6/12 = 1.3
1.2 occurs four times, more than any other number
When the data is put in ascending order the 6th number is 1.3, as is the 7th. So the median is 1.3.
In ascending order: 1.1, 1.2, 1.2, 1.2, 1.2, 1.3, 1.3, 1.3, 1.4, 1.4, 1.5, 1.5
The lowest number is 1.1 and the highest is 1.5. Thus the range is 0.4.
What is the interquartile range?
The lowest 25% numbers are 1.1, 1.2, 1.2; the highest 25% are 1.4, 1.5, 1.5. Removing these six numbers, the range of the remaining ones is 1.4 - 1.2 = 0.2
What is the mean absolute deviation?
The deviations of the twelve numbers (number - mean) are:
0, -0.1, -0.1, -0.2, 0.2, 0.1, 0, -0.1, -0.1, 0.2, 0.1, 0
MAD = (0 + 0.1 + 0.1 + 0.2 + 0.2 + 0.1 + 0 + 0.1 + 0.1 + 0.2 + 0.1 + 0)/12 = 0.1
What is the variance (to 3 decimal places)?
|
Deviations: |
0 |
-0.1 |
-0.1 |
-0.2 |
0.2 |
0.1 |
0 |
-0.1 |
-0.1 |
0.2 |
0.1 |
0 |
|
Deviations squared: |
0 |
0.01 |
0.01 |
0.04 |
0.04 |
0.01 |
0 |
0.01 |
0.01 |
0.04 |
0.01 |
0 |
Sum deviations squared = 0.18; variance = 0.18/(12 –1) = 0.016364
What is the standard deviation (to 3 decimal places)?
Standard deviation = square root variance = 0.12792
Coefficient
Variable
Standard
Deviation / Mean .12792/1.3 =
.0984
0 Clear all Statistical data
1.1 
:1 shows entry
1.2 
:2
1.2 
:3
etc :12
1.3
calculates the Mean
.1279
calculates the Standard Deviation