This graphical display identifies the 5-number-summary 1.3.14 associated with the minimum, quartiles 1.3.9, and the maximum. That is, \(y_1, Q_1, Q_2, Q_3, y_n\text{.}\) These values separate the data roughly into quarters. To distinguish these quarters connect \(y_1\) and \(Q_1\) with a straight line (a whisker) and do the same with \(Q_3\) and \(y_n\text{.}\) Use a box to connect \(Q_1\) with \(Q_2\) and the same to connect \(Q_2\) with \(Q_3\text{.}\) Then the boxed areas also identify the IQR.