Box plot

The box plot is suitable for comparing range and distribution for groups of numerical data, illustrated by a box with whiskers, and a center line in the middle. The whiskers represent high and low reference values for excluding outlier values.

You can define the box start and end points, and whiskers ranges with a few different presets, or define your own settings using expressions.

1. First whisker
2. Box start
3. Center line
4. Box end
5. Last whisker

When to use it

The box plot is suitable for comparing range and distribution for groups of numerical data.

Advantages: The box plot organizes large amounts of data, and visualizes outlier values.

Disadvantages: The box plot is not relevant for detailed analysis of the data as it deals with a summary of the data distribution.

Creating a box plot

You can create a box plot on the sheet you are editing.

In a box plot you need to use one or two dimensions, and one measure. If you use a single dimension you will receive a single box visualization. If you use two dimensions, you will get one box for each value of the second, or outer, dimension.

By default, the Standard (Tukey) preset is used.

Styling the box plot

You have a number of styling options available under Appearance in the properties panel.

Click Styling under Appearance > Presentation to further customize the styling of the chart. The styling panel contains various sections under the General and Chart tabs. You can reset your styles by clicking next to each section. Clicking Reset all resets styles in both General and Chart.

Customizing the text

You can set the text for the title, subtitle, and footnote under Appearance > General. To hide these elements, turn off Show titles.

The visibility of the different labels on the chart depends on chart-specific settings and label display options. These can be configured in the properties panel.

You can style the text that appears in the chart.

Do the following:

1. In the properties panel, expand the Appearance section.

2. Under Appearance > Presentation, click Styling.

3. On the General tab, set the font, emphasis style, font size, and color for the following text elements:

   • Title

   • Subtitle

   • Footnote

4. On the Chart tab, set the font, font size, and color for the following text elements:

   • Axis title: Style the titles on the axes.

   • Axis label: Style the labels on the axes.

Customizing the background

You can customize the background of the chart. The background can be set by color or to an image.

Do the following:

1. In the properties panel, expand the Appearance section.

2. Under Appearance > Presentation, click Styling.

3. On the General tab of the styling panel, select a background color (single color or expression) or set the background to an image from your media library.

   When using a background image, you can adjust image sizing and position.

Changing the definition of the box plot

You can use one of the three presets, found under Box plot elements in the properties panel, to define your box plot.

• Standard (Tukey)

  This preset is based on the original box plot definition by J. Tukey. The center line represents the median (second quartile), and the box start and end points represent the first and third quartiles. Whisker length can be set to 1, 1.5 or 2 inter-quartile ranges. An inter-quartile range represents the difference between the first and third quartiles.

• Percentile-based

  This preset is also defined with the box start and end points representing the first and third quartiles, and the center line representing the median, but the whisker length is adjusted by setting a percentile based whisker position.

• Standard deviation

  This preset is based on standard deviations, with the center line representing the average value, and the box start and end points representing one standard deviation variance. You can set the whisker length to a multiple of standard deviations.

You can also define a custom box plot where you set the value of each box plot element using an expression.