The GENMOD Procedure 
PROC GENMOD Statement 
The PROC GENMOD statement invokes the procedure. You can specify the following options.
specifies the SAS data set containing the data to be analyzed. If you omit the DATA= option, the procedure uses the most recently created SAS data set.
specifies that the levels of the response variable for the ordinal multinomial model and the binomial model with single variable response syntax be sorted in the reverse of the default order. For example, if RORDER=FORMATTED (the default), the DESCENDING option causes the levels to be sorted from highest to lowest instead of from lowest to highest. If RORDER=FREQ, the DESCENDING option causes the levels to be sorted from lowest frequency count to highest instead of from highest to lowest.
specifies the length of effect names in tables and output data sets to be n characters long, where n is a value between 20 and 200 characters. The default length is 20 characters.
specifies the sorting order for the levels of the classification variables (specified in the CLASS statement). This order determines which parameters in the model correspond to each level in the data, so the ORDER= option can be useful when you use the CONTRAST or ESTIMATE statement. Note that the ORDER= option applies to the levels for all classification variables. The exception is the default ORDER=FORMATTED for numeric variables for which you have supplied no explicit format. In this case, the levels are ordered by their internal value. Note that this represents a change from previous releases for how class levels are ordered. Before SAS 8, numeric class levels with no explicit format were ordered by their BEST12. formatted values, and to revert to the previous order you can specify this format explicitly for the affected classification variables. The change was implemented because the former default behavior for ORDER=FORMATTED often resulted in levels not being ordered numerically and usually required the user to intervene with an explicit format or ORDER=INTERNAL option to get the more natural order. The following table displays the valid keywords and describes how PROC GENMOD interprets them.
ORDER=keyword 
Levels Sorted by 

DATA 
order of appearance in the input data set 
FORMATTED 
external formatted value, except for numeric 
variables with no explicit format, which are 

sorted by their unformatted (internal) value 

FREQ 
descending frequency count; levels with the 
most observations come first in the order 

INTERNAL 
unformatted value 
By default, ORDER=FORMATTED. For ORDER=FORMATTED and ORDER=INTERNAL, the sort order is machine dependent.
For more information about sorting order, refer to the chapter on the SORT procedure in the Base SAS Procedures Guide.
specifies plots to be created using ODS Graphics. Many of the observational statistics in the output data set can be plotted using this option. You are not required to create an output data set in order to produce a plot. When you specify only one plot request, you can omit the parentheses around the plot request. Here are some examples:
PLOTS=ALL PLOTS=PREDICTED PLOTS=(PREDICTED RESCHI) PLOTS(UNPACK)=DFBETA
You must enable ODS Graphics before requesting plots, for example, like this:
ods graphics on; proc genmod plots=all; model y = x; run; ods graphics off;
displays formatted levels of the SUBJECT= effect instead of plot symbols. This option applies only to diagnostic statistics for models fit by GEEs that are plotted against cluster number, and provides a way to identify cluster level names with corresponding ordered cluster numbers.
displays multiple plots individually. The default is to display related multiple plots in a panel.
produces all available plots.
plots the Cook’s distance statistic as a function of observation number.
plots the deletion statistic as a function of observation number for each regression parameter in the model.
plots the standardized deletion statistic as a function of observation number for each regression parameter in the model.
plots the leverage as a function of observation number.
includes confidence limits in the predicted value plot.
plots as a function of observation number.
plots as a function of linear predictor.
plots as a function of observation number.
plots as a function of linear predictor.
plots as a function of observation number.
plots as a function of linear predictor.
plots as a function of observation number.
plots as a function of linear predictor.
plots as a function of observation number.
plots as a function of linear predictor.
plots as a function of observation number.
plots as a function of linear predictor.
plots the cluster leverage as a function of ordered cluster.
plots the cluster Cook’s distance statistic as a function of ordered cluster.
plots the studentized cluster Cook’s distance statistic as a function of ordered cluster.
plots the cluster deletion statistic as a function of ordered cluster for each regression parameter in the model.
plots the standardized cluster deletion statistic as a function of ordered cluster for each regression parameter in the model.
specifies the sorting order for the levels of the response variable. This order determines which intercept parameter in the model corresponds to each level in the data. If RORDER=FORMATTED for numeric variables for which you have supplied no explicit format, the levels are ordered by their internal values. Note that this represents a change from previous releases for how class levels are ordered. Before SAS 8, numeric class levels with no explicit format were ordered by their BEST12. formatted values, and to revert to the previous order you can specify this format explicitly for the response variable. The change was implemented because the former default behavior for RORDER=FORMATTED often resulted in levels not being ordered numerically and usually required the user to intervene with an explicit format or RORDER=INTERNAL to get the more natural ordering. The following table displays the valid keywords and describes how PROC GENMOD interprets them.
RORDER=keyword 
Levels Sorted by 

DATA 
order of appearance in the input data set 
FORMATTED 
external formatted value, except for numeric 
variables with no explicit format, which are 

sorted by their unformatted (internal) value 

FREQ 
descending frequency count; levels with the 
most observations come first in the order 

INTERNAL 
unformatted value 
By default, RORDER=FORMATTED. For RORDER=FORMATTED and RORDER=INTERNAL, the sort order is machine dependent. The DESCENDING option in the PROC GENMOD statement causes the response variable to be sorted in the reverse of the order displayed in the previous table. For more information about sorting order, refer to the chapter on the SORT procedure in the Base SAS Procedures Guide.
The NOPRINT option, which suppresses displayed output in other SAS procedures, is not available in the PROC GENMOD statement. However, you can use the Output Delivery System (ODS) to suppress all displayed output, store all output on disk for further analysis, or create SAS data sets from selected output. You can suppress all displayed output with the statement ODS SELECT NONE; and turn displayed output back on with the statement ODS SELECT ALL;. See Table 37.4 and Table 37.5 for the names of output tables available from PROC GENMOD. For more information about ODS, see Chapter 20, Using the Output Delivery System.
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