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6.3: Box Plots

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    51814
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    A box plot is a plot that shows \(Q_1\), \(Q_3\) and MD (= \(Q_2\)) along with H and L (= \(Q_0\) and \(Q_4\)) as shown in Figure 6.3. It especially emphasizes the IQR.

    fig46png-300x92.jpg
    Figure 6.3: The features of a box plot, also known as a box-and-whiskers plot. When one of the whiskers is more than 1.5 times the length of the box (the IQR) then there are outliers by our definition in Section 6.2. The data line shown below the box plot is a construction line and not part of the box plot.

    Example 6.5 : Construct a box plot for the data shown in Figure 6.4. Again, someone has done the first, tedious, step of ordering the data for us.

    fig47png-300x109.jpg
    Figure 6.4: Construction of a box plot from the given data.

    Box plots can also be drawn vertically. SPSS draws box plots vertically; this is especially useful for comparing datasets.


    This page titled 6.3: Box Plots is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Gordon E. Sarty via source content that was edited to the style and standards of the LibreTexts platform.