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Statistics – Median:

The median of a numerical data set is the value in the middle most when the data is arranged in ascending or descending order. It is the halfway point in a data set also known as the positional average .we know in triangles median is a line that divides the opposite side into equal lengths giving area being divided exactly 50%.50% of the values of the distribution are less than the median(left of median) and 50% are greater than the median (right of median).

Hence median is considered as a measure of central tendency. Median is less affected by Outliers or extreme values. Median can be also used as a measure of position (quartiles and deciles). Median can also be termed as the second quartile or 50^th percentile. It is also affected by sampling fluctuations. Used to summarize ordinal or highly skewed interval or ratio scores interval or ratio scores.

To calculate median first we need to

Arrange the values in ascending or descending order.

check the number of values n or N is even or odd .

If N is ODD

median = value in the middle position

Example: {3, 8, 10, 7, 5, 14, 2, 9, 8}

After arranging the order we have set as {2, 3, 5, 7, 8, 8, 9, 10, 14}

Median = middle value =8

If N is Even

Median = average of values left after dividing set in to two equal groups.

Example:

{26, 31, 21, 29, 32, 26, 25, 28}