Boxplots

Box plots, also known as box-and-whisker plots, are a type of plot used to depict a distribution by representing its quartile values. In such plots, the upper and lower sides of the box represent the twenty-fifth and seventy-fifth percentiles (also called the first and third quartiles), while the horizontal line within the box represents the median of the data. The difference between the first and third quartiles is defined as Inter-Quartile Range (IQR), and it is often used as a measure of statistical dispersion of a distribution. The upper whisker represents the higher values up to 1.5*IQR of the upper quartile, while the lower whisker represents lower values within 1.5*IQR of the lower quartile. The pieces of data not in the whisker range are plotted as points and are defined as outliers. You can get additional details and references in the package website shown at the end of the chapter.

In this section, we will see some examples of boxplots using the dataset created in the...