topic Re: Specify the sample size desired with pps and stratification PROC SURVEYSELECT in SAS Programming

Specify the sample size desired with pps and stratification PROC SURVEYSELECT

dewittme — Fri, 17 Aug 2018 18:30:10 GMT

I trying to create a sampling frame. It is a unique problem in that I want to divide a population into two samples that have been stratified by several variables (Demographics/Gender/ etc). I however don't just want a sample of the population, I want to divide the data into two sample, A and B.

I have run a proc freq to get the marginal probabilities and have joined them to my original data.

Is there a way to specify to proc surveyselect how to say I want a sample with 50% of my data? The samplesize arguments specify the samples per strata which is not what I want exactly.

Any help would be appreciated.

Re: Specify the sample size desired with pps and stratification PROC SURVEYSELECT

ballardw — Fri, 17 Aug 2018 18:50:27 GMT

You might provide a small example of your data and what you would expect a possible result to look like after your process.

You may only need the Groups= option.

Both the SAMPSIZE and SAMPRATE options allow use of a data set to control the numbers/rates per strata combination. So if you set that up correctly using your proc freq information that might be what you are looking for. This would be a different data set than your set to sample from and must have a specific structure. So read the documentation.

Anything where you specify one or more strata your selection rate/size is your responsibility to get the "total" that you want.

Re: Specify the sample size desired with pps and stratification PROC SURVEYSELECT

dewittme — Fri, 17 Aug 2018 19:10:36 GMT

Thanks for the advice to read the documentation.

Re: Specify the sample size desired with pps and stratification PROC SURVEYSELECT

dewittme — Fri, 17 Aug 2018 19:13:16 GMT

Ended up using the SRS method and just verifying the marginal probabilities afterwards. This worked fine.

PROC SURVEYSELECT data = mydata
 method = srs 
 n= 2648
 seed = 1234
 out = srs_method
 ;
RUN;

Re: Specify the sample size desired with pps and stratification PROC SURVEYSELECT

mkeintz — Sat, 18 Aug 2018 00:25:47 GMT

Mark your message as a solution. It doesn't matter that you specified the solution to your own topic.