The LIFEREG Procedure

PROC LIFEREG Statement

PROC LIFEREG <options>;

The PROC LIFEREG statement invokes the LIFEREG procedure. Table 69.1 summarizes the options available in the PROC LIFEREG statement.

Table 69.1: PROC LIFEREG Statement Options

Option	Description
COVOUT	Writes the estimated covariance matrix to the OUTEST= data set
DATA=	Specifies the input SAS data set
GOUT=	Specifies a graphics catalog
INEST=	Specifies an input SAS data set that contains initial estimates
NAMELEN=	Specifies the length of effect names
NOPRINT	Suppresses the display of the output
ORDER=	Specifies the sort order for the levels of the classification variables
OUTEST=	Specifies an output SAS data set
PLOTS=	Controls graphics created by ODS Graphics
XDATA=	Specifies a SAS input data containing values for the independent variables

You can specify the following options in the PROC LIFEREG statement.

COVOUT

writes the estimated covariance matrix to the OUTEST= data set if convergence is attained.

DATA=SAS-data-set

specifies the input SAS data set used by PROC LIFEREG. By default, the most recently created SAS data set is used.

GOUT=graphics-catalog

specifies a graphics catalog in which to save graphics output.

INEST=SAS-data-set

specifies an input SAS data set that contains initial estimates for all the parameters in the model. See the section INEST= Data Set for a detailed description of the contents of the INEST= data set.

NAMELEN=n

specifies the length of effect names in tables and output data sets to be n characters, where n is a value between 20 and 200. The default length is 20 characters.

NOPRINT

suppresses the display of the output. Note that this option temporarily disables the Output Delivery System (ODS). For more information, see Chapter 20: Using the Output Delivery System.

ORDER=DATA | FORMATTED | FREQ | INTERNAL

specifies the sort order for the levels of the classification variables (which are specified in the CLASS statement).

This option applies to the levels for all classification variables, except when you use the (default) ORDER=FORMATTED option with numeric classification variables that have no explicit format. In that case, the levels of such variables are ordered by their internal value.

The ORDER= option can take the following values:

Value of ORDER=	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 sort order, see the chapter on the SORT procedure in the Base SAS Procedures Guide and the discussion of BY-group processing in SAS Language Reference: Concepts.

OUTEST=SAS-data-set

specifies an output SAS data set containing the parameter estimates, the maximized log likelihood, and, if the COVOUT option is specified, the estimated covariance matrix. See the section OUTEST= Data Set for a detailed description of the contents of the OUTEST= data set.

PLOTS=NONE | PROBPLOT

specifies options that control graphics created by ODS Graphics.

ODS Graphics must be enabled before plots can be requested. For example:

ods graphics on;

proc lifereg plots=probplot;
   model y = x;
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.

The following plot-requests are available.

NONE	suppresses any plots created by ODS Graphics specified in other LIFEREG statements, such as the BAYES or PROBPLOT statement.
PROBPLOT	creates a default probability plot based on information in the MODEL statement. If a PROBPLOT option is also specified, the probability plot specified in the PROBPLOT statement is created, and this option is ignored.

XDATA=SAS-data-set

specifies an input SAS data set that contains values for all the independent variables in the MODEL statement and variables in the CLASS statement for probability plotting. If there are covariates specified in a MODEL statement and a probability plot is requested with a PROBPLOT statement, you specify fixed values for the effects in the MODEL statement with the XDATA= data set. See the section XDATA= Data Set for a detailed description of the contents of the XDATA= data set.