Question

define measure of dispersion and write merits and demerits
​

Answer 1

Answer:

Measures of dispersion describe the spread of data around a central value (mean, median or mode). There are two measures of dispersion: range (where you subtract the lowest score from the highest score) and standard deviation (SD) – which calculates the spread of scores around the mean.

merits:- Merits

• They indicate the dispersal character of a statistical series.
• They speak of the reliability, or dependability of the average value of a series.
• They enable the statisticians for making a comparison between two or more statistical series with regard to the character of their stability or consistency.
• They facilitate in controlling the variability of a phenomenon under his purview.
• They facilitate in making further statistical analysis of the series through the devices like co-efficient of skewness, co-efficient of correlation, variance analysis etc.
• They supplement the measures of central tendency in finding out more and more information relating to the nature of a series.

demerits

• They are liable to misinterpretations, and wrong generalizations by a statistician of based character.
• They are liable to yield inappropriate results as there are different methods of calculating the dispersions.
• Exception on or two, of the methods of dispersion involve complicated process of computation.
• They may give a value of variation, which may not be practically found with the items of the series.