-
ALPHA=
-
sets the level for confidence limits. The value of must be between 0 and 1, and the default is 0.05. A confidence level of produces % confidence limits. The default of ALPHA=0.05 produces 95% confidence limits.
You request confidence limits for percentages with the CL option, and you request confidence limits for weighted frequencies with the CLWT option. See the sections Confidence Limits for Proportions and Confidence Limits for Totals for more information.
The ALPHA= option also applies to confidence limits for the risks and risk difference, which you request with the RISK option, and to confidence limits for the odds ratio and relative risks, which you request with the OR option. See the sections Risks and Risk Difference and Odds Ratio and Relative Risks for details.
-
CHISQ <(options)>
-
requests the Rao-Scott chi-square test. This is a design-adjusted test that is computed by applying a design correction to
the weighted Pearson chi-square statistic. By default, PROC SURVEYFREQ provides a first-order Rao-Scott chi-square test. If
you specify CHISQ(SECONDORDER), the procedure provides a second-order (Satterthwaite) Rao-Scott chi-square test. See the section Rao-Scott Chi-Square Test for details.
For one-way tables, the CHISQ option produces a design-based goodness-of-fit test. By default, this is a goodness-of-fit test
for equal proportions. If you specify the null hypothesis proportions in the TESTP= option, the CHISQ option produces a chi-square goodness-of-fit test for the specified proportions.
By default for one-way tables, and for first-order tests for two-way tables, the design correction is computed from proportion
estimates. If you specify CHISQ(MODIFIED), the design correction is computed from null hypothesis proportions. For second-order tests for two-way tables, the design
correction is always computed from null hypothesis proportions.
You can specify the following options in parentheses after the CHISQ option:
-
FIRSTORDER
-
requests a first-order Rao-Scott chi-square test. This is the default for the CHISQ option; if you do not specify CHISQ(SECONDORDER), the procedure provides a first-order Rao-Scott test.
-
MODIFIED
-
uses the null hypothesis proportions to compute the Rao-Scott design correction. By default (if you do not specify CHISQ(MODIFIED)),
the procedure uses proportion estimates to compute the design correction for all first-order tests and for second-order tests
for one-way tables. For second-order tests for two-way tables, the procedure always uses null hypothesis proportions to compute
the design correction.
-
SECONDORDER
-
requests a second-order (Satterthwaite) Rao-Scott chi-square test. See the section Rao-Scott Chi-Square Test for details.
-
CL <(options)>
-
requests confidence limits for the percentages (proportions) in the crosstabulation table. By default, PROC SURVEYFREQ computes
standard Wald (“linear”) confidence limits for proportions by using the variance estimates that are based on the sample design. See the section Confidence Limits for Proportions for more information. The procedure determines the confidence coefficient from the ALPHA= option, which by default equals 0.05 and produces 95% confidence limits.
You can specify options in parentheses after the CL option to control the confidence limit computations. You can use the TYPE= option to request an alternative confidence limit type. In addition to Wald confidence limits, the following types of design-based
confidence limits are available for proportions: modified Clopper-Pearson (exact), modified Wilson (score), and logit confidence
limits.
If you specify the PSMALL option, PROC SURVEYFREQ uses the alternative confidence limit type for extreme (small or large) proportion estimates and
uses Wald confidence limits for all other proportion estimates. If you do not specify the PSMALL option, PROC SURVEYFREQ computes
the specified confidence limit type for all proportion values.
You can specify the following options in parentheses after the CL option:
-
ADJUST=NO | YES
-
controls the degrees-of-freedom adjustment to the effective sample size for the modified Clopper-Pearson and Wilson confidence
limits. By default, ADJUST=YES. If you specify ADJUST=NO, the confidence limit computations do not apply the degrees-of-freedom
adjustment to the effective sample size. See the section Modified Confidence Limits for details.
The ADJUST= option is available for TYPE=CLOPPERPEARSON and TYPE=WILSON confidence limits.
-
PSMALL <=p>
-
uses the alternative confidence limit type that you specify with the TYPE= option for extreme (small or large) proportion
values.
The PSMALL value p defines the range of extreme proportion values, where those proportions less than or equal to p or greater than or equal to (1 – p) are considered to be extreme, and those proportions between p and (1 – p) are not extreme. If you do not specify a PSMALL value p, PROC SURVEYFREQ uses p = 0.25 by default. For , the procedure computes Wald confidence limits for proportions between 0.25 and 0.75 and computes the alternative confidence
limit type for proportions less than or equal to 0.25 or greater than or equal to 0.75.
The PSMALL value p must be a nonnegative number. You can specify p as a proportion between 0 and 0.5. Or you can specify p in percentage form as a number between 1 and 50, and PROC SURVEYFREQ converts that number to a proportion. The procedure
treats the value 1 as the percentage form 1%.
The PSMALL option is available for TYPE=CLOPPERPEARSON, TYPE=LOGIT, and TYPE=WILSON confidence limits. See the section Confidence Limits for Proportions for details.
-
TRUNCATE=NO | YES
-
controls the truncation of the effective sample size for the modified Clopper-Pearson and Wilson confidence limits. By default,
TRUNCATE=YES truncates the effective sample size if it is larger than the original sample size. If you specify TRUNCATE=NO,
the effective sample size is not truncated. See the section Modified Confidence Limits for details.
The TRUNCATE= option is available for TYPE=CLOPPERPEARSON and TYPE=WILSON confidence limits.
-
TYPE=name
-
specifies the type of confidence limits to compute for proportions. If you do not specify the TYPE= option, PROC SURVEYFREQ
computes Wald confidence limits (TYPE=WALD) by default.
If you specify the CL(PSMALL) option, the procedure uses the specified confidence limit type for extreme proportions (outside the PSMALL range) and uses
Wald confidence limits for proportions that are not outside the range. If you do not specify the CL(PSMALL) option, the procedure
uses the specified confidence limit type for all proportions.
The following names are available for the TYPE= option:
-
CLOPPERPEARSON | CP
-
requests modified Clopper-Pearson (exact) confidence limits for proportions. See the section Modified Clopper-Pearson Confidence Limits for details.
-
LOGIT
-
requests logit confidence limits for proportions. See the section Logit Confidence Limits for details.
-
WALD
-
requests standard Wald (“linear”) confidence limits for proportions. This is the default confidence limit type if you do not specify the TYPE= option. See
the section Wald Confidence Limits for details.
-
WILSON | SCORE
-
requests modified Wilson (score) confidence limits for proportions. See the section Modified Wilson Confidence Limits for details.
-
CLWT
-
requests confidence limits for the weighted frequencies (totals) in the crosstabulation table. PROC SURVEYFREQ determines
the confidence coefficient from the ALPHA= option, which by default equals 0.05 and produces 95% confidence limits. See the section Confidence Limits for Totals for more information.
-
COLUMN <(option)>
-
displays the column percentage (estimated proportion of the column total) for each cell in a two-way table. The COLUMN option
also provides the standard errors of the column percentages. See the section Row and Column Proportions for more information. This option has no effect for one-way tables.
You can specify the following option in parentheses after the COLUMN option:
-
DEFF
-
displays the design effect for each column percentage in the crosstabulation table. See the section Design Effect for more information.
-
CV
-
displays the coefficient of variation for each percentage (proportion) estimate in the crosstabulation table. See the section
Coefficient of Variation for more information.
-
CVWT
-
displays the coefficient of variation for each weighted frequency (estimated total), in the crosstabulation table. See the
section Coefficient of Variation for more information.
-
DEFF
-
displays the design effect for each overall percentage (proportion) estimate in the crosstabulation table. See the section
Design Effect for more information.
To request design effects for row or column percentages, specify the DEFF option in parentheses after the ROW or COLUMN option.
-
DF=df
-
specifies the degrees of freedom for the analysis. The value of df must be a nonnegative number. By default, PROC SURVEYFREQ computes the degrees of freedom as described in the section Degrees of Freedom.
PROC SURVEYFREQ uses the DF= value in computing confidence limits for proportions, totals, and other statistics. See the section
Confidence Limits for Proportions for details. PROC SURVEYFREQ also uses the DF= value in computing the denominator degrees of freedom for the F statistics in the Rao-Scott and Wald chi-square tests. See the sections Rao-Scott Chi-Square Test, Rao-Scott Likelihood Ratio Chi-Square Test, Wald Chi-Square Test, and Wald Log-Linear Chi-Square Test for more information.
-
EXPECTED
-
displays expected weighted frequencies (totals) for the table cells in a two-way table. The expected weighted frequencies
are computed under the null hypothesis that the row and column variables are independent. See the section Expected Weighted Frequency for more information. This option has no effect for one-way tables.
-
LRCHISQ <(options)>
-
requests the Rao-Scott likelihood ratio chi-square test. This is a design-adjusted test that is computed by applying a design
correction to the weighted likelihood ratio chi-square statistic. By default, PROC SURVEYFREQ provides a first-order Rao-Scott
likelihood ratio test. If you specify LRCHISQ(SECONDORDER), the procedure provides a second-order (Satterthwaite) Rao-Scott likelihood ratio test. See the section Rao-Scott Likelihood Ratio Chi-Square Test for details.
For one-way tables, the LRCHISQ option produces a design-based likelihood ratio goodness-of-fit test. By default, the null
hypothesis is equal proportions. If you specify null hypothesis proportions in the TESTP= option, the LRCHISQ option produces a design-based likelihood ratio test for the specified proportions.
By default for one-way tables, and for first-order tests for two-way tables, the design correction is computed from proportion
estimates. If you specify LRCHISQ(MODIFIED), the design correction is computed from null hypothesis proportions. For second-order tests for two-way tables, the design
correction is always computed from null hypothesis proportions.
You can specify the following options in parentheses after the LRCHISQ option:
-
FIRSTORDER
-
requests a first-order Rao-Scott likelihood ratio test. This is the default for the LRCHISQ option; if you do not specify
LRCHISQ(SECONDORDER), the procedure provides a first-order Rao-Scott test.
-
MODIFIED
-
uses the null hypothesis proportions to compute the Rao-Scott design correction. By default (if you do not specify LRCHISQ(MODIFIED)),
the procedure uses proportion estimates to compute the design correction for all first-order tests and for second-order tests
for one-way tables. For second-order tests for two-way tables, the procedure always uses null hypothesis proportions to compute
the design correction.
-
SECONDORDER
-
requests a second-order (Satterthwaite) Rao-Scott likelihood ratio test. See the section Rao-Scott Likelihood Ratio Chi-Square Test for details.
-
NOCELLPERCENT
-
suppresses the display of overall cell percentages in the crosstabulation table, as well as the standard errors of the percentages.
The NOCELLPERCENT option does not suppress the display of row or column percentages, which you request with the ROW or COLUMN option.
-
NOFREQ
-
suppresses the display of cell frequencies in the crosstabulation table. The NOFREQ option also suppresses the display of
row, column, and overall table frequencies.
-
NOPERCENT
-
suppresses the display of all percentages in the crosstabulation table. The NOPERCENT option also suppresses the display of
standard errors of the percentages. Use the NOCELLPERCENT option to suppress display of overall cell percentages but allow display of row or column percentages.
-
NOPRINT
-
suppresses the display of frequency and crosstabulation tables but displays all requested statistical tests. Note that this
option disables the Output Delivery System (ODS) for the suppressed tables. For more information, see Chapter 20: Using the Output Delivery System.
-
NOSPARSE
-
suppresses the display of variable levels with zero frequency in two-way tables. By default, the procedure displays all levels
of the column variable within each level of the row variable, including any column variable levels with zero frequency for
that row. For multiway tables, the procedure displays all levels of the row variable for each layer of the table by default,
including any row variable levels with zero frequency for the layer.
-
NOSTD
-
suppresses the display of all standard errors in the crosstabulation table.
-
NOTOTAL
-
suppresses the display of row totals, column totals, and overall totals in the crosstabulation table.
-
NOWT
-
suppresses the display of weighted frequencies in the crosstabulation table. The NOWT option also suppresses the display of
standard errors of the weighted frequencies.
-
OR | RELRISK
-
requests estimates of the odds ratio, the column 1 relative risk, and the column 2 relative risk for tables. The OR option also provides confidence limits for these statistics. See the section Odds Ratio and Relative Risks for details.
To compute confidence limits for the odds ratio and relative risks, PROC SURVEYFREQ determines the confidence coefficient
from the ALPHA= option, which by default equals 0.05 and produces 95% confidence limits.
-
PLOTS <(global-plot-options)> <=plot-request <(plot-options)>>
PLOTS <(global-plot-options)>
<=(plot-request <(plot-options)> <…plot-request <(plot-options)>>)>
-
controls the plots that are produced through ODS Graphics. Plot-requests identify the plots, and plot-options control the appearance and content of the plots. You can specify plot-options in parentheses after a plot-request. A global-plot-option applies to all plots for which it is available unless it is altered by a specific plot-option. You can specify global-plot-options in parentheses after the PLOTS option.
When you specify only one plot-request, you can omit the parentheses around the plot-request. For example:
plots=all
plots=wtfreqplot
plots=(wtfreqplot oddsratioplot)
plots(only)=(riskdiffplot relriskplot)
ODS Graphics must be enabled before plots can be requested. For example:
ods graphics on;
proc surveyfreq;
tables treatment*response / chisq plots=wtfreqplot;
weight wt;
run;
ods graphics off;
For more information about enabling and disabling ODS Graphics, see the section Enabling and Disabling ODS Graphics in Chapter 21: Statistical Graphics Using ODS.
If ODS Graphics is enabled but you do not specify the PLOTS= option, PROC SURVEYFREQ produces all plots that are associated
with the analyses that you request with the exception of weighted frequency plots and mosaic plots. To produce a weighted
frequency plot or mosaic plot when ODS Graphics is enabled, you must specify the WTFREQPLOT or MOSAICPLOT plot-request, respectively, in the PLOTS= option, or you must specify the PLOTS=ALL option. PROC SURVEYFREQ produces the remaining plots (listed in Table 90.5) by default when you request the corresponding TABLES statement options. You can suppress default plots and request specific
plots by using the PLOTS(ONLY)= option; PLOTS(ONLY)=(plot-requests) produces only the plots that are specified as plot-requests. You can suppress all plots by specifying the PLOTS=NONE option.
See Figure 90.4 and Figure 90.7 for examples of plots that PROC SURVEYFREQ produces. For general information about ODS Graphics, see Chapter 21: Statistical Graphics Using ODS.
Plot Requests
Table 90.5 lists the available plot-requests together with their required TABLES statement options. Descriptions of the plot-requests follow the table in alphabetical order.
Table 90.5: Plot Requests
The following plot-requests are available with the PLOTS= option:
-
ALL
-
requests all plots that are associated with the specified analyses. If you specify the PLOTS=ALL option, PROC SURVEYFREQ produces
the weighted frequency and mosaic plots that are associated with the tables that you request. (PROC SURVEYFREQ does not produce
weighted frequency and mosaic plots by default when ODS Graphics is enabled.)
-
MOSAICPLOT <(plot-option)>
-
requests a mosaic plot. Mosaic plots are available for crosstabulation tables. For multiway tables, PROC SURVEYFREQ provides
a mosaic plot for each two-way table layer.
To produce a mosaic plot, you must specify the MOSAICPLOT plot-request in the PLOTS= option, or you must specify the PLOTS=ALL option. PROC SURVEYFREQ does not produce mosaic plots by default when ODS Graphics is enabled.
Mosaic plots display tiles that correspond to the crosstabulation table cells. The areas of the tiles are proportional to
the weighted frequencies of the table cells. The column variable is displayed on the X axis, and the tile widths are proportional
to the relative weighted frequencies of the column variable levels. The row variable is displayed on the Y axis, and the tile
heights are proportional to the relative weighted frequencies of the row levels within column levels. The colors of the tiles
correspond to the row variable levels. See Friendly (2000) for more information.
You can specify the following plot-option in parentheses after the MOSAICPLOT plot-request:
-
SQUARE
-
produces a square mosaic plot, where the height of the Y axis equals the width of the X axis. In a square mosaic plot, the
scale of the relative weighted frequencies is the same on both axes. By default, PROC SURVEYFREQ produces a rectangular mosaic
plot.
-
NONE
-
suppresses all plots.
-
ODDSRATIOPLOT <(plot-options)>
-
requests a plot of odds ratios with confidence limits. Odds ratio plots are available for multiway tables and display the odds ratio (with confidence limits) for each table layer. To produce an odds ratio plot, you must also specify the OR option in the TABLES statement for a multiway table.
Table 90.6 lists the plot-options that are available for odds ratio plots. See the subsection “Plot Options for ODDSRATIOPLOT, RELRISKPLOT, and RISKDIFFPLOT” for descriptions of the plot-options.
Table 90.6: Plot Options for ODDSRATIOPLOT, RELRISKPLOT, and RISKDIFFPLOT
Plot Option
|
Description
|
Values
|
CLDISPLAY=
|
Error bar type
|
SERIF, LINE, or BAR
|
COLUMN=
|
Risk column
|
1 or 2
|
LOGBASE=
|
Axis scale
|
2, E, or 10
|
NPANELPOS=
|
Statistics per graphic
|
Number (All)
|
ORDER=
|
Order of two-way levels
|
ASCENDING or DESCENDING
|
RANGE=
|
Range to display
|
Values or CLIP
|
STATS
|
Displays statistics
|
None
|
Default
|
Available for RELRISKPLOT and RISKDIFFPLOT
|
Available for ODDSRATIOPLOT and RELRISKPLOT
|
-
RELRISKPLOT <(plot-options)>
-
requests a plot of relative risks with confidence limits. Relative risk plots are available for multiway tables and display the relative risk (with confidence limits) for each table layer. To produce a relative risk plot, you must also specify the OR option in the TABLES statement for a multiway table.
Table 90.6 lists the plot-options that are available for relative risk plots. See the subsection “Plot Options for ODDSRATIOPLOT, RELRISKPLOT, and RISKDIFFPLOT” for descriptions of the plot-options.
-
RISKDIFFPLOT <(plot-options)>
-
requests a plot of risk differences with confidence limits. Risk difference plots are available for multiway tables and display the risk difference (with confidence limits) for each table layer. To produce a risk difference plot, you must also specify the RISK, RISK1, or RISK2 option in the TABLES statement for a multiway table.
Table 90.6 lists the plot-options that are available for risk difference plots. See the subsection “Plot Options for ODDSRATIOPLOT, RELRISKPLOT, and RISKDIFFPLOT” for descriptions of the plot-options.
-
WTFREQPLOT <(plot-options)>
-
requests a weighted frequency plot. Weighted frequency plots are available for frequency and crosstabulation tables. For multiway
tables, PROC SURVEYFREQ provides a two-way weighted frequency plot for each two-way table layer.
To produce a weighted frequency plot, you must specify the WTFREQPLOT plot-request in the PLOTS= option, or you must specify the PLOTS=ALL option. PROC SURVEYFREQ does not produce weighted frequency plots by default when ODS Graphics is enabled.
By default, PROC SURVEYFREQ displays weighted frequency plots as bar charts. You can specify the TYPE=DOTPLOT plot-option to display frequency plots as dot plots. You can plot weighted percentages instead of frequencies by specifying the SCALE=PERCENT plot-option. There are four frequency plot layouts available, which you can request by specifying the TWOWAY= plot-option. See the subsection “Plot Options for WTFREQPLOT” for more information.
By default, the primary grouping of graph cells in a two-way layout is by column variable. Row variable levels are then displayed
within column variable levels. You can specify the GROUPBY=ROW plot-option to group first by row variable.
Weighted frequency plots for one-way tables display confidence limits by default. For two-way tables, weighted frequency plots
display confidence limits by default in the TWOWAY=GROUPVERTICAL and TWOWAY=GROUPHORIZONTAL layouts. You can suppress confidence limits by specifying the CLBAR=NO plot-option. Confidence limits are not available for two-way plots in the TWOWAY=CLUSTER and TWOWAY=STACKED layouts.
Table 90.7 lists the plot-options that are available for weighted frequency plots. See the subsection “Plot Options for WTFREQPLOT” for descriptions of the plot-options.
Table 90.7: Plot Options for WTFREQPLOT
Plot Option
|
Description
|
Values
|
CLBAR=
|
Confidence limit bars
|
YES or NO
|
GROUPBY=
|
Primary group
|
COLUMN or ROW
|
NPANELPOS=
|
Sections per panel
|
Number (4)
|
ORIENT=
|
Orientation
|
VERTICAL or HORIZONTAL
|
SCALE=
|
Scale
|
WTFREQ or PERCENT
|
TWOWAY=
|
Two-way layout
|
CLUSTER, GROUPHORIZONTAL,
|
|
|
GROUPVERTICAL, or STACKED
|
TYPE=
|
Type
|
BARCHART or DOTPLOT
|
Default
|
|
|
For two-way tables
|
|
|
Global Plot Options
A global-plot-option applies to all plots for which the option is available unless it is altered by an individual plot-option. All plot-options that are listed in Table 90.7 and Table 90.6 are available as global-plot-options. The ONLY option is also available as a global-plot-option.
You can specify global-plot-options in parentheses after the PLOTS option. For example:
plots(order=ascending stats)=(riskdiffplot oddsratioplot)
plots(only)=wtfreqplot
In addition to the plot-options that are listed in Table 90.7 and Table 90.6, you can specify the following global-plot-option in parentheses after the PLOTS option:
-
ONLY
-
suppresses the default plots and requests only the plots that are specified as plot-requests.
Plot Options for ODDSRATIOPLOT, RELRISKPLOT, and RISKDIFFPLOT
You can specify the following plot-options in parentheses after the ODDSRATIOPLOT, RELRISKPLOT, or RISKDIFFPLOT plot-request:
-
CLDISPLAY=SERIF | LINE | BAR <width>
-
controls the appearance of the confidence limit error bars. The default value is CLDISPLAY=SERIF, which displays the confidence
limits as lines with serifs. CLDISPLAY=LINE displays the confidence limits as plain lines without serifs.
CLDISPLAY=BAR displays the confidence limits as bars. By default, the width of the bars equals the size of the marker for
the estimate. You can control the width of the bars and the size of the marker by specifying the value of width as a percentage of the distance between bars, . The bar might disappear when the value of width is very small.
-
COLUMN=1 | 2
-
specifies the table column to use to compute the risk (proportion). The COLUMN= plot-option is available for the relative risk plot (RELRISKPLOT) and the risk difference plot (RISKDIFFPLOT). If you specify COLUMN=1,
the plot displays the column 1 relative risks or the column 1 risk differences. Similarly, if you specify COLUMN=2, the plot
displays the column 2 relative risks or risk differences.
The COLUMN= plot-option does not apply to odds ratio plots. The default is COLUMN=1 for relative risks plots.
If you request both column 1 and column 2 risk differences with the RISK option, COLUMN=1 is the default for the risk difference plot. If you request computation of only column 1 (or only column
2) risk differences with the RISK1 (or RISK2) option, by default the risk difference plot displays the corresponding risk differences.
-
LOGBASE=2 | E | 10
-
applies to the odds ratio plot (ODDSRATIOPLOT) and the relative risk plot (RELRISKPLOT). The LOGBASE= plot-option displays the odds ratio or relative risk axis on the log scale that you specify.
-
NPANELPOS=n
-
divides the plot into multiple panels that display at most statistics (odds ratios, relative risks, or risk differences) per panel. If n is positive, the number of statistics per panel is balanced; if n is negative, the number of statistics per panel is not balanced. For example, suppose you want to display 21 odds ratios.
NPANELPOS=20 displays two panels, the first with 11 odds ratios and the second with 10 odds ratios; NPANELPOS=–20 displays
20 odds ratios in the first panel but only one in the second panel.
By default, n = 0 and all statistics are displayed in a single panel.
-
ORDER=ASCENDING | DESCENDING
-
displays the statistics (odds ratios, relative risks, or risk differences) in sorted order. By default, the statistics are
displayed in the order in which the two-way table layers appear in the multiway table.
-
RANGE=(<min> <,max>) | CLIP
-
specifies the range of values to display. If you specify RANGE=CLIP, the confidence limits are clipped and the display range
is determined by the minimum and maximum values of the estimates. By default, the display range includes all confidence limits.
-
STATS
-
displays the values of the statistics and their confidence limits on the right side of the plot. If you do not specify the
STATS option, the statistic values are not displayed.
Plot Options for WTFREQPLOT
You can specify the following plot-options in parentheses after the WTFREQPLOT plot-request:
-
CLBAR=NO | YES
-
controls the confidence limit error bars in the plots. CLBAR=NO suppresses confidence limit error bars. CLBAR=YES is the default
for all weighted frequency plots except two-way plots that are displayed in the TWOWAY=CLUSTER or TWOWAY=STACKED layout. Confidence limit error bars are not available in the TWOWAY=CLUSTER and TWOWAY=STACKED layouts.
-
GROUPBY=COLUMN | ROW
-
specifies the primary grouping for two-way weighted frequency plots. The default is GROUPBY=COLUMN, which groups graph cells
first by column variable and displays row variable levels within column variable levels. You can specify GROUPBY=ROW to group
first by row variable. In two-way and multiway table requests, the column variable is the last variable specified and forms
the columns of the crosstabulation table. The row variable is the next-to-last variable specified and forms the rows of the
table.
By default for a bar chart that is displayed in the TWOWAY=STACKED layout, bars correspond to the column variable levels and row levels are displayed (stacked) within each column bar. By default
for a bar chart that is displayed in the TWOWAY=CLUSTER layout, bars are first grouped by column variable levels, and row levels are displayed as adjacent bars within each column-level
group. You can reverse the default row and column variable groupings by specifying GROUPBY=ROW.
-
NPANELPOS=n
-
divides a two-way weighted frequency plot into multiple panels that display at most sections per panel. Sections correspond to row or column variable levels, depending on the type of plot and the grouping.
The NPANELPOS= plot-option applies to two-way plots that are displayed in the TWOWAY=GROUPVERTICAL or TWOWAY=GROUPHORIZONTAL layout. The NPANELPOS= plot-option does not apply to the TWOWAY=CLUSTER and TWOWAY=STACKED layouts, which are always displayed in a single panel.
If n is positive, the number of sections per panel is balanced; if n is negative, the number of sections per panel is not balanced. For example, suppose your two-way table has 21 sections. NPANELPOS=20
displays two panels, the first with 11 sections and the second with 10 sections; NPANELPOS=–20 displays 20 sections in the
first panel but only 1 section in the second panel.
By default, n = 4 and each panel includes at most four sections.
-
ORIENT=HORIZONTAL | VERTICAL
-
controls the orientation of the weighted frequency plot. The ORIENT=HORIZONTAL plot-option places the variable levels on the Y axis and the weighted frequencies or percentages on the X axis. ORIENT=VERTICAL places
the variable levels on the X axis. The default is ORIENT=VERTICAL for bar charts (TYPE=BARCHART) and ORIENT=HORIZONTAL for dot plots (TYPE=DOTPLOT).
-
SCALE=WTFREQ | PERCENT
-
specifies the scale of the frequencies to display. SCALE=WTFREQ displays weighted frequencies (totals), and SCALE=PERCENT
displays percentages. The default is SCALE=WTFREQ.
-
TWOWAY=CLUSTER | GROUPHORIZONTAL | GROUPVERTICAL | STACKED
-
specifies the layout for two-way weighted frequency plots.
All TWOWAY= layouts are available for bar charts (TYPE=BARCHART). All TWOWAY= layouts except TWOWAY=CLUSTER are available for dot plots (TYPE=DOTPLOT). Confidence limits (CLBAR=) can be displayed in the GROUPVERTICAL and GROUPHORIZONTAL layouts. Confidence limits are not available in the STACKED and
CLUSTER layouts. The ORIENT= and GROUPBY= plot-options are available for all TWOWAY= layouts.
The default two-way layout is TWOWAY=GROUPVERTICAL, which produces a grouped plot that has a vertical common baseline. By
default for bar charts (TYPE=BARCHART, ORIENT=VERTICAL), the X axis displays column variable levels, and the Y axis displays weighted frequencies. The plot includes a vertical
(Y-axis) block for each row variable level. The relative positions of the graph cells in this plot layout are the same as
the relative positions of the table cells in the crosstabulation table. You can reverse the default row and column grouping
by specifying the GROUPBY=ROW plot-option.
The TWOWAY=GROUPHORIZONTAL layout produces a grouped plot that has a horizontal common baseline. By default (GROUPBY=COLUMN), the plot displays a block on the X axis for each column variable level. Within each column-level block, the plot displays
row variable levels.
The TWOWAY=STACKED layout produces stacked displays of weighted frequencies. By default (GROUPBY=COLUMN) in a stacked bar chart, the bars correspond to column variable levels, and row levels are stacked within each column level.
By default in a stacked dot plot, the dotted lines correspond to column levels, and cell weighted frequencies are plotted
as data dots on the corresponding column line. The dot color identifies the row level.
The TWOWAY=CLUSTER layout, which is available only for bar charts, displays groups of adjacent bars. By default, the primary
grouping is by column variable level, and row levels are displayed within each column level.
You can reverse the default row and column grouping in any layout by specifying the GROUPBY=ROW plot-option. The default is GROUPBY=COLUMN, which groups first by column variable.
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TYPE=BARCHART | DOTPLOT
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specifies the type of the weighted frequency plot. TYPE=BARCHART produces a bar chart and TYPE=DOTPLOT produces a dot plot.
The default type is TYPE=BARCHART.
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RISK | RISKDIFF
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requests risk statistics for tables. The RISK option also provides standard errors and confidence limits for these statistics. Risk statistics include the row 1 risk (proportion),
row 2 risk, overall risk, and risk difference. See the section Risks and Risk Difference for details.
The RISK option provides both column 1 and column 2 risks. To request only column 1 or column 2 risks, use the RISK1 or RISK2 option.
To compute confidence limits for the risks and risk difference, PROC SURVEYFREQ determines the confidence coefficient from
the ALPHA= option, which by default equals 0.05 and produces 95% confidence limits.
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RISK1
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requests column 1 risk statistics for tables, together with their standard errors and confidence limits. Risk statistics include the row 1 risk (proportion), row
2 risk, overall risk, and risk difference. See the section Risks and Risk Difference for details.
To compute confidence limits for the risks and risk difference, PROC SURVEYFREQ determines the confidence coefficient from
the ALPHA= option, which by default equals 0.05 and produces 95% confidence limits.
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RISK2
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requests column 2 risk statistics for tables, together with their standard errors and confidence limits. Risk statistics include the row 1 risk (proportion), row
2 risk, overall risk, and risk difference. See the section Risks and Risk Difference for details.
To compute confidence limits for the risks and risk difference, PROC SURVEYFREQ determines the confidence coefficient from
the ALPHA= option, which by default equals 0.05 and produces 95% confidence limits.
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ROW <option>
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displays the row percentage (estimated proportion of the row total) for each cell in a two-way table. The ROW option also provides the standard errors of the row percentages. See the
section Row and Column Proportions for more information. This option has no effect for one-way tables.
You can specify the following option in parentheses after the ROW option:
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DEFF
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displays the design effect for each row percentage in the crosstabulation table. See the section Design Effect for more information.
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TESTP=(values)
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specifies null hypothesis proportions (test percentages) for chi-square tests for one-way tables (goodness-of-fit tests). You can separate values with blanks or commas. Specify values in probability form as numbers between 0 and 1, where the proportions sum to 1. Or specify values in percentage form as numbers between 0 and 100, where the percentages sum to 100. PROC SURVEYFREQ treats the value 1 as
the percentage form 1%. The number of TESTP= values must equal the number of variable levels in the one-way table. List these
values in the same order in which the corresponding variable levels appear in the output.
When you specify the TESTP= option, PROC SURVEYFREQ displays the specified test percentages in the one-way frequency table.
The TESTP= option has no effect for two-way tables.
PROC SURVEYFREQ uses the TESTP= values for the one-way Rao-Scott chi-square test (CHISQ) and for the one-way Rao-Scott likelihood ratio chi-square test (LRCHISQ). See the sections Rao-Scott Chi-Square Test and Rao-Scott Likelihood Ratio Chi-Square Test for details.
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VAR
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displays the variance estimate for each percentage in the crosstabulation table. See the section Proportions for details. By default, PROC SURVEYFREQ displays the standard errors of the percentages.
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VARWT
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displays the variance estimate for each weighted frequency, or estimated total, in the crosstabulation table. See the section
Totals for details. By default, PROC SURVEYFREQ displays the standard deviations of the weighted frequencies.
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WCHISQ
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requests the Wald chi-square test for two-way tables. See the section Wald Chi-Square Test for details.
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WLLCHISQ
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requests the Wald log-linear chi-square test for two-way tables. See the section Wald Log-Linear Chi-Square Test for details.
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WTFREQ
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displays totals (weighted frequencies) and their standard errors when you do not specify a WEIGHT or REPWEIGHTS statement. PROC SURVEYFREQ displays the weighted frequencies by default when you include a WEIGHT or REPWEIGHTS statement.
Without a WEIGHT or REPWEIGHTS statement, PROC SURVEYFREQ assigns all observations a weight of one.