SAS Proc Summary with class variables that have missing values

Question

I'm having an issue with how proc summary behaves when variables in the class statement have missing values. In the example below, test_out will give all possible combinations of types. test_missing_out does not and does not take into account var3 for the sum where var2 was missing, despite the fact var1 was not missing:

data test;
    infile datalines dsd delimiter=' ';
    input var1 var2 $ var3;
    datalines;
1 data 200
2 data2 103
;
run;

proc summary
    data=test;
    class var1 var2;
    var var3;
    output out=test_out sum=sum;
run;


data test_missing;
    infile datalines dsd delimiter=' ';
    input var1 var2 $ var3;
    datalines;
1 data 200
2  103
;
run;

proc summary
    data=test_missing;
    class var1 var2;
    var var3;
    output out=test_missing_out sum=sum; 
run;

mvherweg mvherweg · Accepted Answer · 2013-07-04T11:13:39

proc summary has a lot in common with proc means concerning syntax. You can simply add the keyword MISSING to the proc summary statement if you want it to consider missing values as a grouping level:

proc summary
data=test_missing
MISSING;
class var1 var2;
var var3;
output out=test_missing_out sum=sum; 
run;

SAS Proc Summary with class variables that have missing values

1 Answers