What are the Requisites of a Good Average?
Requisites of a good average are as follows:
- It should be simple to compute.
- It should be easy to understand.
- It should be rigidly defined.
- It should be representative of all the items.
- It should not be unduly affected by extreme values.
- It should be capable of further algebraic treatment.
Arithmetic mean : It is simple to understand and compute and is rigidly defined but is affected by extreme items. It is a calculated value and not based on position in the series.
Median : It is not influenced by extreme values and is, thus, specially useful for open-end classes. It indicates the value of middle item in the distribution. But median is not capable of algebraic treatment and is affected more by sampling fluctuations.
Mode : It is the most representative value of the distribution and not affected by extreme values. It can be determined Mathematically as well as graphically. But sometimes mode is ill defined and is not capable of algebraic treatment. Mode is not based on each and every item of the series and is not a rigidly defined value.