Boxes

Interquartile range boxes on a boxplot represent the middle 50% of the data. The whiskers extend to the maximum and minimum data points within 1.5 box heights. For example, the following boxplot displays interquartile range boxes that represent the heights for plants grown with three different fertilizers.

Interquartile range boxes appear by default on boxplots. To edit interquartile range boxes, select and double-click the boxes that you want to edit. For more information on selecting boxes, go to Select groups and single items on a graph.

Edit the appearance of the boxes

On the Attributes tab, you can edit the fill type, fill color, line type, and line color of the selected boxes.

Tip

To change the default settings and attributes for graph elements, choose File > Options > Graphics.

Edit the box endpoints

On the Options tab, under Box Endpoints, select one of the following:

• Quartiles: (default) Display the box bottom at the 1st quartile (25th percentile) and box top at the 3rd quartile (75th percentile).
• Hinges: Like quartiles, hinges measure the middle half of the data, but they are calculated differently. In practice, the hinges may be a bit closer to the median than the quartiles are, but in most cases this difference is not noticeable unless the data set is very small.
• Percentile: Use percentiles to define the bottom and top of the box. Enter a percentile between 0 and 50.

Remove the whiskers

On the Options tab, under Whiskers, select None.

Edit the box widths

On the Options tab, select Box width proportional to sample size to make the width of each box proportional to the square root of the sample size.

You can edit the fill type, fill color, line type, line color, and width of range boxes.

1. Double-click the graph.
2. Select and double-click the boxes that you want to edit.

   Note

   For more information on selecting range boxes, go to Select groups and single items on a graph.

3. Make the edits that you want.

   Edit the appearance of the boxes

   On the Attributes tab, you can edit the fill type, fill color, line type, and line color of range boxes.

   Tip

   To change the default settings and attributes for graph elements, choose File > Options > Graphics.

   Edit the box widths

   On the Options tab, select Box width proportional to sample size to make the width of each box proportional to the square root of the sample size.

You can change the appearance, confidence level, whiskers, and widths of median confidence interval boxes.

1. Double-click the graph.
2. Select and double-click the boxes that you want to edit.

   Note

   For more information on selecting range boxes, go to Select groups and single items on a graph.

3. Make the edits that you want.

   Edit the appearance of the boxes

   On the Attributes tab, you can edit the fill type, fill color, line type, and line color of the selected boxes.

   Tip

   To change the default settings for graph elements, choose File > Options > Graphics.

   Edit the confidence level

   (Not available for marginal plots) On the Options tab, in Confidence level, enter the level of confidence for the confidence interval. Usually, a confidence level of 95% works well. A 95% confidence level indicates that, if you take 100 random samples from the population, the confidence intervals for approximately 95 of the samples will contain the median.

   Show the whiskers

   (Not available for marginal plots) On the Options tab, under Whiskers, select Show.

   Edit the box widths

   (Not available for marginal plots) On the Options tab, select Box width proportional to sample size to make the width of each box proportional to the square root of the sample size.