topic Re: First by Groups in SAS Programming

First by Groups

anandas — Thu, 24 Aug 2017 18:01:51 GMT

Hello

I have a dataset like this currently;

id term program
1 201102 Arts
1 201103 Arts
1 201201 Metal
2 200701 Arts
2 200702 Arts
3 201003 Arts
3 201003 Arts
3 201003 Arts
3 201201 Fashion
3 201202 Fashion

I want to create a new variable called "First_Term" and identify the first term by program, term and id. It should look like this.

id term program First_term
1 201102 Arts First term
1 201103 Arts Returning
1 201201 Metal First term
2 200701 Arts First term
2 200702 Arts Returning
3 201003 Arts First term
3 201003 Arts Returning
3 201003 Arts Returning
3 201201 Fashion First term
3 201202 Fashion Returning

I do not know how to do this? Please help.

Thanks.

Re: First by Groups

Reeza — Thu, 24 Aug 2017 18:07:40 GMT

It's very similar to this question, except you want a character value.

https://stats.idre.ucla.edu/sas/faq/how-can-i-create-an-enumeration-variable-by-groups/

If you use the method in the link, you can then recode 1 to "First" and anything else to "Returning".

Re: First by Groups

Astounding — Thu, 24 Aug 2017 18:38:53 GMT

In the long term, @Reeza is 100% right in that you need to study and learn these tools. However, beginning with a problem that requires your data sorted by 3 variables might be a little daunting. So here is one way:

proc sort data=have;

by id program term;

run;

data want;

set have;

by id program;

if first.program then first_term='First term';

else first_term='Returning';

run;

I made some assumptions about what is really needed here, since the rules for assigning "First term" vs. "Returning" don't appear (to me) to be consistent in your example.

Re: First by Groups

anandas — Thu, 24 Aug 2017 19:11:02 GMT

Thank you to both. I looked at Reeza's article and replaced with string and worked like a charm. Earlier I was using the same code only but to use 'and' instead of 'or'.

Thanks.