The MVPDIAGNOSE Procedure

SCOREPLOT Statement

  • SCOREPLOT < / options>;

The SCOREPLOT statement produces a single score plot, which is a scatter plot of the scores that are associated with a pair of principal components. You can use the SCOREMATRIX statement to display a matrix of score plots for more than two principal components.

Table 11.4 summarizes the options available in the SCOREPLOT statement.

Table 11.4: SCOREPLOT Statement Options

Option

Description

ALPHA=

Specifies the $\alpha $ value for the prediction ellipse

ELLIPSE

Requests a prediction ellipse to be overlaid on the score plot

GROUP=

Specifies a variable for grouping points in the score plot

LABELS=

Specifies which points in the score plot are to be labeled

ODSFOOTNOTE=

Adds a footnote to the score matrix

ODSFOOTNOTE2=

Adds a secondary footnote to the score matrix

ODSTITLE=

Specifies a title for the score matrix

ODSTITLE2=

Specifies a secondary title for the score matrix

XCOMP=

Specifies the principal component whose scores are plotted on the horizontal axis

YCOMP=

Specifies the number of principal components whose scores are plotted on the vertical axis


You can specify the following options in the SCOREPLOT statement. The section Common Plot Statement Options describes additional options that are available in all plot statements.

ALPHA=$\alpha $

specifies the $\alpha $ value for a prediction ellipse that is overlaid on the score plot. The probability that a new observation falls outside the ellipse is $\alpha $. The default is 0.05. If you specify the ALPHA= option, you do not need to specify the ELLIPSE option.

ELLIPSE

requests that a prediction ellipse be overlaid on the principal component score plot. The probability that a new observation falls outside the ellipse is specified by the ALPHA= option.

GROUP=variable

specifies a variable in the input data set that is used to group the points in the score plot. Points that have different GROUP= values are plotted with different markers or colors (or both) to distinguish the groups.

LABELS=ON | OFF | OUTSIDE

specifies which points in the score plot to label. Points are labeled with the values of the first variable listed in the ID statement, or the observation number if no ID statement is specified. By default, LABELS=ON and all points are labeled. You can specify LABELS=OFF to suppress all point labels.

If you overlay a prediction ellipse on the score plot by specifying the ELLIPSE or ALPHA= option, you can specify LABELS=OUTSIDE to label only the points outside the prediction ellipse.

XCOMP=x

specifies an integer x that identifies the principal component whose scores are plotted on the horizontal axis of the score plot. The default is 1. You cannot specify the same principal component number in both the XCOMP= and YCOMP= options.

YCOMP=y

specifies an integer y that identifies the principal component whose scores are plotted on the vertical axis of the score plot. The default is $\mr{mod}(x, j) + 1$, where x is the value that is specified by the XCOMP= option and j is the number of principal components in the model. You cannot specify the same principal component number in both the XCOMP= and YCOMP= options.