# Stats - Outliers

What is an outlier?

An extreme value.

What is an outlier which is not correct called?

An anomaly.

What is the process of removing anomalies called?

Cleaning the data.

What does $\ll$ mean?

Much less than.

What does $\gg$ mean?

Much greater than.

What is the typical definition of an outlier?

Any value that is over $1.5$ the interquartile range away from the upper or lower quartile.

Should you add an outlier to a box plot?

Yes.

Where are the two places a “whisker” should go after you’ve removed an outlier?

- At the next acceptable value.
- At the outlier boundary.