How does one read a box plot?

A box plot, also known as a whisker plot, effectively represents the five-number summary of a data set. This summary includes the minimum value, the first quartile (Q1), the median (Q2), the third quartile (Q3), and the maximum value. The box itself indicates the interquartile range, which captures the middle 50% of the data, while the "whiskers" extend to the minimum and maximum values that are not considered outliers.

Understanding the five-number summary is crucial because it provides insights into the distribution of the data, including its central tendency and variability. For example, the median provides a measure of the central location of the data, and the quartiles highlight the range within which the central half of the data falls. Therefore, the box plot is an essential tool for visually summarizing data and making comparisons across different data sets based on these five key statistics.