"Outliers" are values that "lie outside" the other values.
When we collect data, sometimes there are values that are "far away" from the main group of data ... what do we do with them?
Example: Long Jump
A new coach has been working with the Long Jump team this month, and the athletes' performance has changed.
Augustus can now jump 0.15m further, June and Carol can jump 0.06m further.
Here are all the results: •Augustus: +0.15m •Tom: +0.11m •June: +0.06m •Carol: +0.06m •Bob: + 0.12m •Sam: -0.56m
Oh no! Sam got worse.
Here are the results on the number line:
The mean is:
(0.15+0.11+0.06+0.06+0.12-0.56) / 6 = -0.06 / 6 = -0.01m
So, on average the performance went DOWN.
The coach is obviously useless ... right?