Basic Analysis and Graphing - SAS

362 Creating Three-Dimensional Scatterplots Chapter 13
Scatterplot 3D Platform Options
When you add an ellipsoid, two formatting options are available:
• Coverage changes the portion of data points covered by the ellipsoid. The larger the value, the bigger the
ellipsoid.
• Transparency changes the surface of the ellipsoid from transparent to opaque. The larger the value, the
more opaque the ellipsoid.
The coverage and transparency options also appear in the red triangle menu after you add the ellipsoid.
When you add normal contour ellipsoids to a 3D scatterplot, you specify whether you want an ellipsoid for
all of the data or for a specific group of data. The ellipsoid for each set of grouped data is color-coded to
differentiate one group from another.
You display and remove normal contour ellipsoids by selecting and deselecting Normal Contour Ellipsoids
from the red triangle menu.
The examples in this section use the Iris.jmp sample data table, which includes measurements of sepal
length, sepal width, petal length, and petal width for three species of iris.
Related Information
• “Example of an Ungrouped Normal Contour Ellipsoid” on page 366
• “Example of Grouped Normal Contour Ellipsoids” on page 367
Nonparametric Density Contours
The nonparametric density contour shows contours that approximately encompass a specified proportion of
the points. You add nonparametric density contours to see patterns in point density when the scatterplot is
darkened by thousands of points.
This feature is particularly valuable when you have many points on a 3D scatterplot; the contours can be so
dark that you cannot see the structure. In this situation, you remove the points so that only the contours are
displayed. See “Optimizing a Dense Nonparametric Density Contour” on page 363 for details.
When you add nonparametric density contours to a 3D scatterplot, you specify whether you want a contour
for all of the data or for a specific group of data. The contour for each set of grouped data is color-coded to
differentiate one group from another.
You display and remove nonparametric density contours by selecting and deselecting Nonpar Density
Contours from the red triangle menu.
Related Information
• “Example of a Grouped Nonparametric Density Contour” on page 368
Density Contour Controls
The Density Contour Controls options are displayed below the 3D scatterplot. These options let you select
additional contours and change each contour’s formatting.