UNIVAR
variable <(voptions)> <…variable <(voptions)>> </ options> ;
The UNIVAR statement computes univariate kernel density estimates. You can specify various voptions for each variable by enclosing them in parentheses after the variable name. You can also specify global options among the UNIVAR statement options following a slash (/). Global options apply to all the variables specified in the UNIVAR statement. However, individual variable voptions override the global options.
Note: The VAR statement supported by PROC KDE in SAS 8 and earlier releases is now obsolete. The VAR statement has been replaced by the UNIVAR and BIVAR statements, which enable you to produce multiple kernel density estimates with a single invocation of the procedure.
Table 48.2 summarizes the options available in the UNIVAR statement.
Table 48.2: UNIVAR Statement Options
Option 
Description 

Specifies a bandwidth multiplier 

Specifies a lower grid limit 

Specifies an upper grid limit 

Specifies the method used to compute the bandwidth 

Specifies a number of grid points 

Suppresses output tables produced 

Specifies the output SAS data set containing the kernel density estimate 

Requests that a table of percentiles 

Requests plots of the univariate kernel density estimate 

Specifies the maximum grid value in determining the SheatherJones plugin bandwidth 

Specifies the minimum grid value in determining the SheatherJones plugin bandwidth 

Specifies the number of grid values used in determining the SheatherJones plugin bandwidth 

Specifies the tolerance for termination of the bisection algorithm 

Produces a table for each variable containing standard univariate statistics and the bandwidth 
You can specify the following options in the UNIVAR statement. As noted, some options can be used as voptions.
Suppose you have the variables x1
, x2
, x3
, and x4
in the SAS data set MyData
. You can request a univariate kernel density estimate for each of these variables with the following statements:
proc kde data=MyData; univar x1 x2 x3 x4; run;
You can also specify different bandwidths and other options for each variable. For example, the following statements request kernel density estimates that use Silverman’s rule of thumb (SROT) method for all variables:
proc kde data=MyData; univar x1 (bwm=2) x2 (bwm=0.5 ngrid=100) x3 x4 / ngrid=200 method=srot; run;
The option NGRID=200 applies to the variables x1
, x3
, and x4
, but the voption NGRID=100 is applied to x2
. Bandwidth multipliers of 2 and 0.5 are specified for the variables x1
and x2
, respectively.