Question

Which of the following is not a measure of variability of a data set?  

	a.	variance
	b.	standard deviation
	c.	median
	d.	coefficient of variation
	e.	range

Answer 1

Solution- Median is not a measure of variability of a data set ,it is a measure of central tendency, it tells about the middle value of a data set (I.e positional value of a data set set.).

Variance tells about the spread of data set, small value of variance shows that data points fall very close to mean and large value of data shows that data points are very spread from the mean.

Small value of standard deviation shows that data are more concentrated about the mean.

Coefficient of variation is the statistical measure in percentage of dispersion of data set.

Range tells the difference between the largest and smallest value of the data set.

Thus we can say that variance, standard deviation, coefficient of variation and range are the measure variability of a data set.