A box plot, also referred to as a whiskers chart, is a graphical representation used to describe the distribution of a sample by simple dispersion and position indexes. A box plot can be represented either horizontally or vertically by means of a rectangular partition divided by two segments. The rectangle (box) is delimited by the first quartile (25^{th} percentile) and the third quartile (75^{th} percentile), and divided by the median (50^{th} percentile), as shown in the following figure:

Figure 3.17: Statistical descriptors of a box plot

Segments outside the box (whiskers) represent the minimum and maximum of the sample. In this way, ...