Common Chart Statement Options :: SAS/QC(R) 12.1 User's Guide

Common Chart Statement Options

You can specify the following options after a slash (/) in an SPECHART or TSQUARECHART statement.

ALPHA=value

specifies the probability used to compute control limits for an SPE or chart. If you specify ALPHA= $\alpha$ , the control limits are computed so that the probability is $\alpha$ that the statistic exceeds its control limits. The value of $\alpha$ can range from 0 to 1. By default, $\alpha$ is 0.05.

CONTRIBUTIONS <(contribution-options)>

creates a contribution plot for each point that falls outside the control limits of the chart. You can specify the following contribution-options in parentheses:

MAXNPLOTS=n: specifies the maximum number, n, of contribution plots to produce. 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 to that value of the statistic are displayed. By default, all variable contributions are displayed.

EXCHART

specifies that a control chart be displayed only when one or more points lie outside the control limits.

specifies the natural time interval between consecutive TIME variable positions when a time, date, or datetime format is associated with the TIME variable. By default, the INTERVAL= option uses the number of positions per panel that you specify with the NPANELPOS= option. The default time interval keywords for various time formats are shown in Table 13.3.

Table 13.3: Default Time Intervals

Time Format	Default Interval
DATE	DAY
DATETIME	DTDAY
DDMMYY	DAY
HHMM	HOUR
HOUR	HOUR
MMDDYY	DAY
MMSS	MINUTE
MONYY	MONTH
TIME	SECOND
TOD	SECOND
WEEKDATE	DAY
WORDDATE	DAY
YYMMDD	DAY
YYQ	QTR

You can use the INTERVAL= option to modify the effect of the NPANELPOS= option, which specifies the number of positions per panel. The INTERVAL= option enables you to match the scale of the horizontal axis to the scale of the TIME variable without having to associate a different format with the TIME variable.

For example, suppose your formatted time values span 100 days and a datetime format is associated with the TIME variable. Since the default interval for the datetime format is dtday and because NPANELPOS=50 by default, the chart is displayed with two panels.

Now suppose your data span 100 hours and a datetime format is associated with the TIME variable. The chart for these data is created in a single panel, but the data occupy only a small fraction of the chart because the scale of the data (hours) does not match that of the horizontal axis (days). If you specify INTERVAL=HOUR, the horizontal axis is scaled for 50 hours, matching the scale of the data, and the chart is displayed with two panels.

NOCHART

suppresses display of the control chart. You can use the NOCHART option with the CONTRIBUTIONS option to produce contribution plots for out-of-control points without displaying the control chart. You can use the NOCHART option with the OUTTABLE= option to save a summary of the control chart to an output data set without displaying the chart.

NOHLABEL

suppresses the horizontal axis label in the control chart.

NOVLABEL

suppresses the vertical axis label in the control chart.

NPANELPOS=n NPANEL=n

specifies the number of horizontal axis plotting positions per panel in the chart. You typically specify the NPANELPOS= option to display more points in a panel than the default number, which is 50.

You can specify a positive or negative value 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, then no balancing is done, and each panel (except possibly the last) displays approximately positions.

ODSFOOTNOTE=FOOTNOTE | FOOTNOTE1 | 'string'

adds a footnote to the chart. If you specify the FOOTNOTE (or FOOTNOTE1) keyword, the value of the SAS FOOTNOTE statement is used as the chart footnote. If you specify a quoted string, that string is used as the footnote. The quoted string can contain the following escaped characters, which are replaced with the values indicated:

$\backslash$ n: is replaced by the TIME variable name.
$\backslash$ l: is replaced by the TIME variable label (or name if the analysis TIME has no label).

ODSFOOTNOTE2=FOOTNOTE2 | 'string'

adds a secondary footnote to the chart. If you specify the FOOTNOTE2 keyword, the value of the SAS FOOTNOTE2 statement is used as the secondary chart footnote. If you specify a quoted string, that string is used as the secondary footnote. The quoted string can contain the following escaped characters, which are replaced with the values indicated:

$\backslash$ n: is replaced by the TIME variable name.
$\backslash$ l: is replaced by the TIME variable label (or name if the TIME variable has no label).

ODSTITLE=TITLE | TITLE1 | NONE | DEFAULT | 'string'

specifies a title for the chart. You can specify the following values:

TITLE (or TITLE1): uses the value of the SAS TITLE statement as the chart title.
NONE: suppresses all titles from the chart.
DEFAULT: uses the default title.

If you specify a quoted string, that string is used as the graph title. The quoted string can contain the following escaped characters, which are replaced with the values indicated:

$\backslash$ n: is replaced by the TIME variable name.
$\backslash$ l: is replaced by the TIME variable label (or name if the analysis variable has no label).

ODSTITLE2=TITLE2 | 'string'

specifies a secondary title for the chart. If you specify the TITLE2 keyword, the value of the SAS TITLE2 statement is used as the secondary chart title. If you specify a quoted string, that string is used as the secondary title. The quoted string can contain the following escaped characters, which are replaced with the values indicated:

$\backslash$ n: is replaced by the TIME variable name.
$\backslash$ l: is replaced by the TIME variable label (or name if the analysis variable has no label).

OUTTABLE=SAS-data-set

creates an output SAS data set that contains the information plotted in the control chart, including the statistic values and control limits. See the section OUTTABLE= Data Set for a description of the OUTTABLE= data set.

OVERLAY

specifies that the separate sequences of observations defined by the SERIES variable and selected by the SERIESVALUE= option be plotted in a single control chart. By default, each sequence is plotted in a separate chart. The OVERLAY option is applicable only when a TIME variable is specified and the input data set contains multiple observations that have the same time value.

SERIESVALUE=value-list

specifies a list of values of the SERIES variable that define one or more sequences of observations to be plotted. If the SERIES variable is a character variable, the value-list must be a list of quoted strings. By default, a series is plotted for each unique value of the SERIES variable. The SERIESVALUE= option is applicable only when a TIME variable is specified and the input data set contains multiple observations that have the same time value.

TOTPANELS=n

specifies the number of panels to use to display the chart. By default, the number of panels is determined by the value that you specify in the NPANELPOS= option. If you specify both the TOTPANELS= and NPANELPOS= options, the TOTPANELS= value takes precedence.

The MVPMONITOR Procedure

Common Chart Statement Options