Box plots and histograms
Since the median and quartiles split the data set into quartiles, they also split a histogram of the data into four approximately equal areas.

What does a box plot tell you about the distribution?
- Centre
- The median gives an indication of the
centre of the distribution.

- Spread
- The width of the box (the interquartile range) and the
difference between the maximum and minimum (range) both give
an indication of the
spread of values.

- Skewness
- The distances of the minimum and lower quartile to the median, in relation
to the corresponding distances of the maximum and upper quartile give information
about the skewness of the distribution. If the maximum and upper
quartile are further from the median, the distribution is skew with a long tail
of higher values.
