Tag Archives: Outlier

Interquartile Range (IQR)

The interquartile range (IQR) is a measure of the spread of a distribution of a single quantitative variable. The IQR is a rather simple calculation and is merely the difference between (hence “range”) the upper quartile (Q3) and the lower quartile (Q1) (hence “inter” and “quartile”). For a better understanding of quartiles, here is a site […]


A box plot, also known as a “box-and-whisker plot,” is a graph used to visually convey the distribution and variation of a single quantitative variable of a set of data on an interval. A box plot prominently features the quartiles, range and outliers of a set of data and can be drawn vertically or horizontally. The […]