
/* change the path */
proc import datafile = "...\Data2stCCS.csv"
            out      = pop 
            dbms     = csv 
			replace;
			DELIMITER=";" ; 
run;



/**********************SELECT two-stage {SI,SI} ***********************/
proc surveyselect data=pop method=srs n=320 seed=1357 out=ech1;
   cluster ID_i;       
run;
proc surveyselect data=ech1 method=srs n=25 seed=7548 out=ech;
   strata ID_i;
run;
  
/* the two-stage sample (of size 8000) is 'ech' */
