The SURVEYFREQ Procedure

The “Data Summary” table provides information about the input data set and the sample design. PROC SURVEYFREQ displays this table unless you specify the NOSUMMARY option in the PROC SURVEYFREQ statement.

The “Data Summary” table displays the total number of valid observations. To be considered valid, an observation must have a nonmissing, positive sampling weight value if you specify a WEIGHT statement. If you do not specify the MISSING option, a valid observation must also have nonmissing values for all STRATA and CLUSTER variables. The number of valid observations can differ from the number of nonmissing observations for an individual table request, which the procedure displays in the frequency or crosstabulation tables. See the section Missing Values for more information.

PROC SURVEYFREQ displays the following information in the “Data Summary” table:

If you specify the LIST option in the STRATA statement, PROC SURVEYFREQ displays a “Stratum Information” table. This table provides the following information for each stratum:

If you specify the VARMETHOD=BRR, VARMETHOD=JACKKNIFE, or NOMCAR option in the PROC SURVEYFREQ statement, the procedure displays a “Variance Estimation” table. If you do not specify any of these options, the procedure creates a “Variance Estimation” table but does not display it. You can store this nondisplayed table in an output data set by using the Output Delivery System (ODS). See the section ODS Table Names for more information.

The “Variance Estimation” table provides the following information:

If you specify the PRINTH method-option for VARMETHOD=BRR, PROC SURVEYFREQ displays the Hadamard matrix used to construct replicates for BRR variance estimation. If you provide a Hadamard matrix with the HADAMARD= method-option for VARMETHOD=BRR but the procedure does not use the entire matrix, the procedure displays only the rows and columns that are actually used to construct replicates.

PROC SURVEYFREQ displays one-way frequency tables for all one-way table requests in the TABLES statements, unless you specify the NOPRINT option in the TABLES statement. A one-way table shows the sample frequency distribution of a single variable, and provides estimates for its population distribution in terms of totals and proportions.

If you request a one-way table without specifying options, PROC SURVEYFREQ displays the following information for each level of the variable:

The one-way table displays weighted frequencies if your analysis includes a WEIGHT or REPWEIGHTS statement, or if you specify the WTFREQ option in the TABLES statement.

The one-way table also displays the Frequency Missing, which is the number of observations with missing values.

You can suppress the frequency counts by specifying the NOFREQ option in the TABLES statement. Also, the NOWT option suppresses the weighted frequencies and their standard deviations. The NOPERCENT option suppresses the percentages and their standard errors. The NOSTD option suppresses the standard errors of the percentages and the standard deviations of the weighted frequencies. The NOTOTAL option suppresses the total row of the one-way table.

PROC SURVEYFREQ optionally displays the following information in a one-way table:

PROC SURVEYFREQ displays all table requests in the TABLES statements, unless you specify the NOPRINT option in the TABLES statement. For two-way to multiway crosstabulation tables, the values of the last variable in the table request form the table columns. The values of the next-to-last variable form the rows. Each level (or combination of levels) of the other variables forms one layer. PROC SURVEYFREQ produces a separate two-way crosstabulation table for each layer of a multiway table.

For each layer, the crosstabulation table displays the row and column variable names and values (levels). Each two-way table lists levels of the column variable within each level of the row variable.

By default, the procedure displays all levels of the column variable within each level of the row variables, 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 levels with zero frequency for that layer. You can suppress the display of zero frequency levels by specifying the NOSPARSE option.

If you request a crosstabulation table without specifying options, the table displays the following information for each combination of variable levels (table cell):

The two-way table displays weighted frequencies if your analysis includes a WEIGHT or REPWEIGHTS statement, or if you specify the WTFREQ option in the TABLES statement.

The two-way table also displays the Frequency Missing, which is the number of observations with missing values.

You can suppress the frequency counts by specifying the NOFREQ option in the TABLES statement. Also, the NOWT option suppresses the weighted frequencies and their standard deviations. The NOPERCENT option suppresses all percentages and their standard errors. The NOCELLPERCENT option suppresses overall cell percentages and their standard errors, but displays any other percentages (and standard errors) that you request, such as row or column percentages. The NOSTD option suppresses the standard errors of the percentages and the standard deviations of the weighted frequencies. The NOTOTAL option suppresses the row totals and column totals, as well as the overall total.

PROC SURVEYFREQ optionally displays the following information in a two-way table:

If you specify the CHISQ option for the Rao-Scott chi-square test or the LRCHISQ option for the Rao-Scott likelihood ratio chi-square test, PROC SURVEYFREQ displays the following information:

If you specify the WCHISQ option for the Wald chi-square test or the WLLCHISQ option for the Wald log-linear chi-square test, PROC SURVEYFREQ displays the following information:

If you specify the RISK option in the TABLES statement for a table, PROC SURVEYFREQ displays “Column 1 Risk Estimates” and “Column 2 Risk Estimates” tables. You can display only column 1 or column 2 risks by specifying the RISK1 or RISK2 option, respectively.

The “Risk Estimates” table displays the following information for Row 1, Row 2, Total, and Difference:

In the “Column 1 Risk Estimates” table, the row 1 risk is the column 1 percentage of row 1. The row 2 risk is the column 1 percentage of row 2, and the total risk is the column 1 percentage of the entire table. The risk difference is the row 1 risk minus the row 2 risk. In the “Column 2 Risk Estimates” table, these computations are based on column 2.

If you specify the OR option in the TABLES statement for a table, PROC SURVEYFREQ displays the “Odds Ratio” table. This table includes the following information: