Friday, April 8, 2011


Definition of Median- The value of a variable that divides a sample in half.
The median is the middle number in a sequence of numbers. This is commonly used in statistics.

How to calculate Median:
Firstly,Arrange the numbers in ascending order.
Then find the number in the middle
If it is odd number
e.g 1,1,3,5,6,8,9
Therefore,the number 5 is the median.
If it is an even sequence
e.g 1,1,3,5,6,8
The median is therefore 4.
When median is usually used?
It is used for comparison accurately.
Use of the median minimises any effects due to extreme (very high or very low) results, and is seen to be a very fair way of assessing participant performance. When determining how far away a result can be from the consensus medianresult (acceptable range of results), the spread of participant results is again used.

When median cannot be used?
the median cannot be used to calculate the aggregate value of items if the number of items is known.