I would be very happy to help.
First, note that my DATA is registered to every student in a classroom within a school.
My goal is to randomly sample K out of N schools in distict school
And in each out of the K school, I want to sample to each level of the sample stratum1, a different number of students
When at 2 levels of the stratum1 we will randomly sample 4 students and at the third level we will sample 5 students.
I think to split the sample so that:
1- Samples K distinct schools from N schools:
proc sort data=my_data ; by school;run;
data my_data ;set my_data ;
by school;
/*Placing a random number for school and for students*/
retain uSchool 0;
if first.school then uschool=ranuni(12222154);
ustudent=ranuni(8744);
run;
proc sql;
ctreate table distinct_schools as
select distinict school,uschool,stratum1, stratum2 , stratum3, stratum4
from my_data;
quit;
proc sort data=distinct_schools ; by uschool;run;
proc surveyselect data=distinct_schools out=K_schools outsorting=k_schools_sort
method=srs sampsize=60 seed=1234;
control stratum2 stratum3 stratum4;
run;
2- and perform another sample, sample 4 students from the 2 levels of stratum1 and at the third level we will sample 5 students.
of 4 ostudents from the K schools for the two tiers separately.
proc sql;
create table Students_frame as
select a.school,b.*
from distinct_schools as a left join my_data as b
on a.school=b.school;
quit;
proc sort data=Students_frame; by uSchool ustudent stratum1;run;
proc surveyselect data=Students_frameout=Students_sample outsorting=sort_Students_sample
method=srs sampsize=( 4 4 5) seed=323161;
strata uschool stratum1;
control stratum2 stratum3 stratum4;
run;
Do you have another suggestion that you do the sampling in one stroke and not split in two?
