Effect of Outliers on Data
Outliers can skew data especially the mean and median from a data set.
If you look at the effects below, without outliers the mean of the data set would have been 3. If you have outlying data with a value of 10, it suddenly changed the mean to 4. In this case the mean didn’t shift that much as it only shifted from 3 to 4.
But if you look in the second scenario, you have the same data set but with 300 as an outlier. The mean shifted from 5.45 to 30, which is a huge shift.
So 1 outlying value can have significant changes to the mean (average) of a data set.
Use a set of data whose distribution across its range looks symmetrical, and change some of the values so that the distribution no longer looks symmetrical. Does the change affect the median more than the mean? Explain your thinking.