[Statistics Tutorial 7] Median



Or POSITIONAL CENTER divides the data into two equal parts. It is the central value of the distribution of the series.

To find the median, it is most important to first arrange the data in ascending or descending order. Then, this formula is applied:

Formula for Median

Formula for Median

Other Features of Median include:

Change in individual numbers will not affect the change in median as it is concerned with finding out the position of data not the content.


Median can therefore be used for open ended class interval




If N happens to be an even number, then Median is taken out as follows:

Formula when N is even

Formula when N is even

Merits of Median:

  1. It is free from the effect of extreme values
  2. Certainty: As it is a specific point in the series
  3. Besides algebraic approach, the median can be arrived at through graphical representation.
  4. It is easier to use median for qualitative observations. E.g. Calculating IQ or health of students etc.

Demerits of Median:

  1. Median can’t be used for further mathematical treatment unlike A.M.
  2. It becomes unrealistic when the median is located between two middle values; it is only an approximate measure not the exact value.
  3. It is not representative when the data is widely spread as it focuses only to the central value.



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