#### Median

The median $m$ of the set of values is a value such as half of the total observations are below and half is above.

* If the size $n$ is odd, it is the value of the $z_{\left(\frac{n+1}{2}\right)}$ where $z_{(i)}$ is the value of the $i$ th observation (when ordered in increasing order).

* If $n$ is even, we can take $\frac{z_{\left(\frac{n}{2}\right)}+z_{\left(\frac{n}{2}+1\right)}}{2}$.

The median is less sensitive than the mean to extreme values.