topic Easy question on Proc Surveyselect in SAS Procedures

Easy question on Proc Surveyselect

deleted_user — Thu, 17 Jul 2008 20:44:17 GMT

Hello everyone,

I have a dataset like:

MD# Volume
1 333
2 22
3 10
4 150
5 250
6 60
.
.
.

I want to randomly select MD, also weighted by Volume, giving high volume ones a higher chance to be selected.
I know there is a SIZE statement I can use as weighting function, but this statement can't be used for Simple Random Selection.
I wonder if anyone can tell me what other options I can use.

Thanks a lot,

SAS User999

Re: Easy question on Proc Surveyselect

Olivier — Fri, 18 Jul 2008 04:45:09 GMT

Hello.
You have to add METHOD=PPS to the PROC SURVEYSELECT statement. PPS is the equivalent of simple random with weights. And use the SIZE statement.
[pre]
PROC SURVEYSELECT DATA=in
OUT=sample
METHOD=pps
SAMPRATE=rate
NOPRINT ;
SIZE volume ;
RUN ;
[/pre]
Regards.
Olivier

Re: Easy question on Proc Surveyselect

deleted_user — Fri, 18 Jul 2008 15:49:44 GMT

Thanks a lot, I tried this before. Here I need to use sampsize statement instead of samprate. PPS has a limitation on sampling size, which depends on relative size of weights variable.

Thank you again for the help