Measures of central tendency are numerical indices of statistical data that are generally indicative of the center, middle or representative of a data set.
Definitions
It is a single value within the range of data which represents a group of individual values simply and concisely so that the mind can get a quick understanding of the general size of the individuals in the group. Since the value lies within the range of data, it is known as a measures of central tendency.
According to R.A. Fisher, “The inherent inability of a human to grasp in its entirely a large body of numerical data compels us to seek relatively few constants that will adequately describe the data”.
Types of central tendency
There are several measures of central tendency. All this measures are collectively called statistical averages. The most commonly used averages are-
- Mean
- Median
- Mode
The Mean can be divided into three types-
- Quartiles
- Percentiles, etc.
Properties
The desired properties of a good measure are following,
- It should be based on all observations of an act of values.
- It should be rigorously defined.
- It should be easily computable.
- It should be least affected by extreme values.
- It should nucleate least from sample to sample drawn from the same population.
Advantages
Some advantages are following
- More precise measure than measure of dispersion.
- Easy to calculate.
- Less time consuming and lower cost.
Disadvantages
The measure of central tendency doesn’t work when outlier occure. That means this measure is affected by outlier.