## Scatter Plot Confidence Ellipses

You can generate confidence ellipses by setting the
options in the multivariate output options dialog,
shown in Figure 40.5, or by choosing from the
**Curves** menu, shown in Figure 40.50.

**Figure 40.50:** Curves Menu

Only 80% prediction confidence ellipses can be selected
in the multivariate output options dialog.
You must use the **Curves** menu to display mean confidence ellipses.
You can use the confidence coefficient slider in the
**Confidence Ellipses** table to change
the coefficient for these ellipses.

Figure 40.35
displays part of a scatter
plot matrix with 80% prediction confidence ellipses
and the **Correlation Matrix** table with corresponding
correlations highlighted.
The ellipses graphically show a small negative correlation
(-0.1176) between variables **SEPALLEN** and **SEPALWID**,
a moderate negative correlation (-0.4284)
between variables **SEPALWID** and **PETALLEN**,
and a large positive correlation (0.8718) between
variables **SEPALLEN** and **PETALLEN**.

Note | The confidence ellipses displayed in this illustration may not be appropriate
since none of the scatter plots suggest bivariate normality. |

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