“Standard Deviation and Coefficient of Dispersion”

What is the relationship between Standard Deviation and Variance ?

• Standard Deviation is the square of the Variance

• Standard Deviation is the half of the Variance

• Standard Deviation is the double of the Variance

• Standard Deviation is the square root of the Variance

Answer explanation

Calculate the Standard Deviation of the following data set : 4,8,7,5 ?

• 8.5

• √17

• √8.5

• 4.25

Answer explanation

Use the formula for ungrouped data

If the standard deviation of a data set is 0, what can you conclude about the data?

• The data set is empty

• All the values in the data set are same

• The data set contains at least one value as 0

• The data set contains only one value

Answer explanation

The sum of the square of the mean difference will become 0 because the mean will be equal to all the data sets.

Calculate the Standard Deviation with the above given data :

• 3

• √9

• √3

• √1.5

Answer explanation

Look at the formula of Standard Deviation for ungrouped data.

What does the Coefficient of Dispersion measures ?

• The central value of the data set

• The uniformity of data relative to median

• The sum of all data points in the dataset

• The maximum and minimum values of a dataset

Answer explanation

In the formula you can see the deviation of the datasets are calculated about median hence it calculates the uniformity.

The deviation of the datasets in the Coefficient of Dispersion is calculated about which of the following measure of central tendency ?

• Regression

• Skewness

• Median

• Kurtosis

Answer explanation

In the formula you can see the deviation of the datasets are calculated median.

A higher value of Coefficient of Dispersion indicates ?

• Larger value of median

• Higher uniformity in the dataset

• Lower uniformity in the dataset

• Smaller size of the dataset

Answer explanation

Higher values of Coefficient of Dispersion gives more deviation from the median that lower uniformity in the dataset

The Coefficient of Dispersion is expressed in__________

• Ratio

• Intrgral Value

• Modulus Value

• Percentage

Answer explanation

It is multiplied by hundred.

Which of the following is the correct formula for Coefficient of Dispersion

• 1

• 2

• 3

• 4

• All of the above

Answer explanation

Remember the formulas.

Calculate the Coefficient of Dispersion for the given dataset about median; 150, 170, 200, 220, 250

• 25%

• 3/20 %

• 15%

• √3/20 %

Answer explanation

The datasets are already arranged in ascending order Just find the median and use the formula.