# Z Score

###### This wiki is incomplete.

The $z$-score of an observation is the number of standard deviations away from the mean it is. Formally, if $\sigma$ is the standard deviation of the normal distribution, $\mu$ is the mean of the distribution, and $x$ is the value, then

$z = \frac{x - \mu}{\sigma}.$

For more on the $z$-score and the normal distribution check out this wiki.

## Z-score Table