Chapter 18: The BOXPLOT Procedure

Overview

The BOXPLOT procedure creates side-by-side box-and-whisker plots of measurements organized in groups. A box-and-whisker plot displays the mean, quartiles, and minimum and maximum observations for a group . Throughout this chapter, this type of plot, which can contain one or more box-and-whisker plots, is referred to as a box plot .

The PLOT statement of the BOXPLOT procedure produces a box plot. You can specify more than one PLOT statement to produce multiple box plots.

You can use options in the PLOT statement to

• control the style of the box-and-whisker plots

• specify one of several methods for calculating quantile statistics (percentiles)

• add block legends and symbol markers to reveal stratificationindata

• display vertical and horizontal reference lines

• control axis values and labels

• overlay the box plot with plots of additional variables

• control the layout and appearance of the plot

The INSET and INSETGROUP statements produce boxes or tables (referred to as insets ) of summary statistics or other data on a box plot. An INSET statement produces an inset of statistics pertaining to the entire box plot. An INSETGROUP statement produces an inset containing statistics calculated separately for each group. An INSET or INSETGROUP statement by itself does not produce a display; it must be used with a PLOT statement.

You can use options in an INSET or INSETGROUP statement to

• specify the position of the inset

• specify a header for the inset

• specify graphical enhancements, such as background colors, text colors, text height, text font, and drop shadows