Introduction to Median
- In statistics and probability, median is the value that separates a set of arranged numbers into a higher and a lower half, signifying the middle of an ascending or descending set.
- Unlike a mean, the value of median is calculated so that the value is not representative of a skewed group of numbers.
- It is a more accurate representation of a ‘typical’ value of that sequence.
Understanding Median
- A median cannot be calculated using a haphazard, unarranged set of numbers as it poses the threat of skewing the values of the set. It is thus arranged in a sequence, usually in ascending or descending order, and the middle value is selected to depict it as the median.
- It's easy to calculate for a set of numbers that are odd in number; after arranging them in a sequence, the middle value is the median.
But for sets of numbers that are even in the number of observations, the middle two values are selected, added and divided by 2 aka. finding the mean of the middle two values.
Median is useful to determine the location parameter, especially when the highest or lowest value (called the outliers) cannot be trusted, mostly because those values can be errors, or more information or proof about their credibility are lacking.
- Median also does not usually require many observations; it is entirely dependent on the middle observations of the arranged set.
Highlights of Median
Median is simple and very easy to calculate. It is also a credible contender to approximating the mean of a set of values, therefore lends itself to various measures of variability.
It is more descriptive and accurate than mean is, making it more statistically efficient.
It is a critical value of measure in calculating the central tendencies in a set of observations, since it has a breakdown point of 50%, depicting the best of both halves where the median divides the set.
