The median is the value in a set of ordered data that divides the data into two parts. It is frequently called the ‘middle value’.
Where the number of observations is odd, the median is the middle value; for example, for the following ordered data set with an odd number of observations, the median value is five.
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Where the number of observations is even, the median is calculated as the mean of the two central values; for example, in the following ordered data set, the two central values are 5 and 6, and median value is the mean of these two values, 5.5.
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The median provides a measure of location of a data set that is suitable for both symmetric and skewed distributions and is also relatively insensitive to outliers.