I am using sas v9.3 proc genmod to model a continuous outcome:
PROC GENMOD;
class number train bl/param=glm;
model y= train age mt pn eo tncc bl;
effectplot fit (x=mt plotby=train)/obs;
repeated subject=number/type=ar rupdate=2;
run;
My class variable train has 8 levels, but the effectplot displays on trainer 1, 4, 5, 6, 7, and 8. Trainers 2 and 3 are ommited for some reason. If a perform a slicefit plotby train, all levels are displayed, but that isn't the graph I really want. Any reason two levels of my class variable are being omitted?
Thanks!
Katy
Most likely reason is that you have insufficient observations to fit a model for those levels, due to missing value in other variables. The following simulated data has a similar structure to what you have specified. Run it and see if you get 8 plots. If so, the problem is probably related to your data:
data have;
call streaminit(1);
do number=1 to 4;
age = 20 + ceil(20*rand("uniform"));
do train=1 to 8;
do j = 1 to 4;
mt = rand("Normal");
y = 2 + age + 3*train - mt + rand("normal");
output;
end;
end;
end;
run;
PROC GENMOD data=have;
class number train /param=glm;
model y= train age mt;
effectplot fit (x=mt plotby=train)/obs;
repeated subject=number/type=ar rupdate=2;
run;
Most likely reason is that you have insufficient observations to fit a model for those levels, due to missing value in other variables. The following simulated data has a similar structure to what you have specified. Run it and see if you get 8 plots. If so, the problem is probably related to your data:
data have;
call streaminit(1);
do number=1 to 4;
age = 20 + ceil(20*rand("uniform"));
do train=1 to 8;
do j = 1 to 4;
mt = rand("Normal");
y = 2 + age + 3*train - mt + rand("normal");
output;
end;
end;
end;
run;
PROC GENMOD data=have;
class number train /param=glm;
model y= train age mt;
effectplot fit (x=mt plotby=train)/obs;
repeated subject=number/type=ar rupdate=2;
run;
Are you ready for the spotlight? We're accepting content ideas for SAS Innovate 2025 to be held May 6-9 in Orlando, FL. The call is open until September 16. Read more here about why you should contribute and what is in it for you!
Learn how use the CAT functions in SAS to join values from multiple variables into a single value.
Find more tutorials on the SAS Users YouTube channel.
Select SAS Training centers are offering in-person courses. View upcoming courses for: