PROC MVPMONITOR: TSQUARECHART Statement

TSQUARECHART Statement

TSQUARECHART < / options> ;

The TSQUARECHART statement produces a $\text{[math]}$ chart based on a principal components model computed by the MVPMODEL procedure. In a Phase I analysis, the SPE statistics are computed by the MVPMODEL procedure and read from the HISTORY= data set. In a Phase II analysis, the $\text{[math]}$ statistics are computed by the MVPMONITOR procedure from information about the principal components model specified in the LOADINGS= data set.

You can specify the following options with the TSQUARECHART statement after a slash (/):

ALPHA=value

specifies the probability used to compute control limits for the $\text{[math]}$ chart. If you specify ALPHA= $\text{[math]}$ , the control limits are computed so that the probability is $\text{[math]}$ that the $\text{[math]}$ statistic exceeds its control limits. The value of $\text{[math]}$ can range between 0 and 1. By default, $\text{[math]}$ is 0.05.

CONTRIBUTIONS <(contribution-options)>

creates a contribution plot for each point that falls outside the control limits of the $\text{[math]}$ chart. You can specify the following contribution-options in parentheses following the CONTRIBUTIONS option:

MAXNPLOTS=n: specifies the maximum number, n, of contribution plots produced. When n is less than the number of points outside the control limits, contribution plots are produced for the first n out-of-control points.
MAXNVARS=n: specifies that only the n contributions with the greatest magnitudes be displayed in the contribution plots. For each out-of-control point, the n variables that contribute the most at that point are displayed. By default, all variable contributions are displayed.

EXCHART

specifies that a $\text{[math]}$ chart be created only when one or more points lie outside the control limits.

NOCHART

suppresses creation of the $\text{[math]}$ chart. You typically specify the NOCHART option when you use the OUTTABLE= option to save results to an output data set. You can also use the NOCHART option along with the CONTRIBUTIONS option to produce contribution plots for out-of-control points without displaying the $\text{[math]}$ chart.

NPANELPOS=n

NPANEL=n

specifies the number of horizontal axis plotting positions per panel of the $\text{[math]}$ chart. You typically specify the NPANELPOS= option to display more points on a panel than the default number, which is 50.

You can specify a positive or negative number for n. The absolute value of n must be at least 5. If n is positive, the number of positions is adjusted so that it is approximately equal to n and so that all panels display approximately the same number of positions. If n is negative, no balancing is done, and each panel (except possibly the last) displays approximately n positions.

OUTTABLE=SAS-data-set

creates an output SAS data set that saves the information plotted on the $\text{[math]}$ chart, including the $\text{[math]}$ statistic values and control limits. See the section OUTTABLE= Data Set for a description of the OUTTABLE= data set.

Note: This procedure is experimental.