This page was adapted from a page titled SAS Programs created by Professor Michael Friendly of York University. We thank Professor Friendly for permission to adapt and distribute this page via our web site.
SAS Procedures exist to carry out all the forms of statistical analysis. A procedure is invoked in a “PROC step” which starts with the keyword PROC, such as:
PROC MEANS DATA=CLASS; VAR HEIGHT WEIGHT;
The VAR or VARIABLES statement can be used with all procedures to indicate which variables are to be analyzed. If this statement is omitted, the default is to include all variables of the appropriate type (character or numeric) for the given analysis.
Some other statements that can be used with most SAS procedure steps are:
- BY variable(s);
- Causes the procedure to be repeated automatically for each different value of the named variable(s). The data set must first be sorted by those variables.
- ID variable(s);
- Give the name of a variable to be used as an observation IDentifier.
- LABEL var=’label’;
- Assign a descriptive label to a variable.
- WHERE (expression);
- Select only those observations for which the expression is true.
For example, the following lines produce separate means for males and females, with the variable SEX labelled ‘Gender’. (An ID statement is not appropriate, because PROC MEANS produces only summary output.)
PROC SORT DATA=CLASS; BY SEX; RUN;
PROC MEANS DATA=CLASS; VAR HEIGHT WEIGHT; BY SEX; LABEL SEX='Gender'; RUN;
If the DATA= option is not used, SAS procedures process the most recently created dataset. In the brief summaries below, the required portions of a PROC step are shown in bold. Only a few representative options are shown.
- PROC CORR
- Correlations among a set of variables.
PROC CORR DATA=SASdataset options; options:NOMISS ALPHA VAR variable(s); WITH variable(s);
- PROC FREQ
- Frequency tables, chi tests
PROC FREQ DATA=SASdataset; TABLES variable(s) / options; options:NOCOL NOROW NOPERCENT OUTPUT OUT=SASdataset;
- PROC MEANS
- Means, standard deviations, and a host of other univariate statistics for a set of
PROC MEANS DATA=SASdataset options; options:N MEAN STD MIN MAX SUM VAR CSS USS VAR variable(s); BY variable(s); OUTPUT OUT=SASdataset keyword=variablename ... ;
Statistical options on the PROC MEANS statement determine which statistics are printed. The (optional) OUTPUT statement is used to create a SAS dataset containing the values of these statistics.
- PROC UNIVARIATE
- Univariate statistics and displays for a set of variables.
PROC UNIVARIATE DATA=SASdataset options; options:PLOT VAR variable(s); BY variable(s); OUTPUT OUT=SASdataset keyword=variablename ... ;
SAS statements and options for regression (PROC REG) are described in more detail in the document PROC REG Summary. SAS statements and options for analysis of variance (PROC ANOVA and PROC GLM) described in the document PROC ANOVA and PROC GLM.
- PROC ANOVA
- Analysis of variance (balanced designs)
PROC ANOVA DATA=SASdataset options; CLASS variable(s); MODEL dependent(s)= effect(s);
- PROC GLM
- General linear models, including ANOVA, regression and analysis of covariance models.
PROC GLM DATA=SASdataset options; CLASS variable(s); MODEL dependent(s)= effect(s); OUTPUT OUT=SASdataset keyword=variablename ... ;
- PROC REG
- Regression analysis
PROC REG DATA=SASdataset options; MODEL dependent(s) = regressors / options; PLOT variable | keyword. * variable | keyword. = symbol ; OUTPUT OUT=SASdataset P=name R=name ... ;
- PROC CHART
- Histograms and bar charts
PROC CHART DATA=SASdataset options; VBAR variable / options; HBAR variable / options; options: MIDPOINTS= GROUP= SUMVAR=
- PROC PLOT
- Scatter plots
PROC PLOT DATA=SASdataset options; options: HPERCENT= VPERCENT= PLOT yvariable * xvariable = symbol / options; PLOT (yvariables) * (xvariables) = symbol / options ; PLOT options: BOX OVERLAY VREF= HREF= BY variable(s) ;
Note that the parenthesized form in the PLOT statement plots each y-variable listed against each x-variable.
- PROC PRINT
- Print a SAS data set
PROC PRINT DATA= SASdataset options; options: UNIFORM LABEL SPLIT='char' VAR variable(s); BY variable(s); SUM variable(s);
- PROC SORT
- Sort a SAS data set according to one or more variables.
PROC SORT DATA=SASdataset options; options: OUT= BY variable(s);