Measures of Dispersion MCQ Questions and Answers for Practice

1. An automobile manufacturer obtains data concerning the sales of six of its deals in the last week of 1996. The results indicate the standard deviation of their sales equals 6 autos. If this is so, the variance of their sales equals:

1. Square root of 6
2. 6
3. (1/square root of 6)
4. 36

2. If standard deviation of the values 2, 4, 6, 8 is 2.236, then standard deviation of the values 4, 8,12, 16 is:

1. 4.472
2. 4.236
3. 2.236

3. Var(X) = 4 and Var(Y) =9. If X and Y are independent random variable then Var(2X + Y) is:

1. 13
2. 17
3. 25
4. -1

4. If = Rs.20, S= Rs.10, then coefficient of variation is:

1. 45%
2. 50%
3. 60%
4. 65%

5. Which of the following measures of dispersion is independent of the units employed?

1. Coefficient of variation
2. Quartile deviation
3. Standard deviation
4. Range

6. The moments about origin are called:

1. Moments about zero
2. Raw moments
3. Both a and c
4. Neither a nor b

7. All odd order moments about mean in a symmetrical distribution are:

1. Positive
2. Negative
3. Zero
4. Three

8. The second moment about arithmetic mean is 16, the standard deviation will be:

1. 16
2. 4
3. 2

9. The first and second moments about arbitrary constant are -2 and 13 respectively, The standard deviation will be:

1. -2
2. 3
3. 9
4. 13

10. Moment ratios β1 and β2 are:

1. Independent of origin and scale of measurement
2. Expressed in original unit of the data
3. Unit less quantities
4. Both a and c

11. The first moment about X = 0 of a distribution is 12.08. The mean is:

1. 10.8
2. 10.08
3. 12.08
4. 12.88

12. First two moments about the value 2 of a variable are 1 and 16. The variance will be:

1. 13
2. 15
3. 16
4. Difficult to tell

13. The first three moments of a distribution about the mean are 1, 4 and 0. The distribution is:

1. Symmetrical
2. Skewed to the left
3. Skewed to the right
4. Normal

14. If the third central is negative, the distribution will be:

1. Symmetrical
2. Positively skewed
3. Negatively skewed
4. Normal

15. If the third moment about mean is zero, then the distribution is:

1. Positively skewed
2. Negatively skewed
3. Symmetrical
4. Mesokurtic