proc reg - "variable is uninitialized" error when trying to only keep coefficient estimates

[UniversitySas]

Hello,

I am running a proc reg, with options: outest = data_set tableout

I am having a weird problem.

In my data-table "Data_set"

I have a column "_TYPE_", and it has repeated values for each regression model I run.

I only want to keep the coefficient estimates and t-stats in my table, but whenever I try:

DATA clean_data;
 
SET data_set;

if _TYPE_ = PARMS;
if _TYPE_ = T;

RUN;

I am getting an error:

NOTE: Variable PARMS is uninitialized

Which doesn't make any sense to me, given that PARMS isn't a variable, it's a value that

_TYPE_ takes on.

Why does sas think i'm referring to a variable here?

I only want to retain the values in my table that have a row corresponding to PARMS (parameter estimates) and T (t-statistic from my regression), for the variable _TYPE_.

Any ideas?

[Jagadishkatam · Accepted solution]

Then you need to use the quotes as below with in operator

DATA clean_data;
 SET data_set;
if _TYPE_ in ('T' 'PARMS' );
RUN;

[UniversitySas]

Thank you so much.

Why is this the case? Is it because the values are characters?

[Jagadishkatam]

yes