I have a large longitudinal dataset and would like to use surveyselect to randomly select a subsample of 5%.
The catch is that I need to select all measures for each client ID, these vary from 1 to 10 measurement occasions.
After an extensive online search I have not been able to find an example.
Here is the syntax I have been working with.
proc surveyselect data = have out= want
method=srs samprate=.05
by ID;
run;
Insights would be greatly appreciated.