Mean outliers bark

like hound dogs for our notice.

It’s just a squirrel.

David Carroll

Many data sets in the real world such as opinion surveys or rainfall amounts contain outliers — a value well outside the “typical grouping”. When using the average, or “mean”, to describe the data, a single outlier has a large effect on the average. When we provide a median value along with the mean it help people better understand the story being told by the data without being distracted by the barking dogs. –David Carroll