DM 'LOG;CLEAR;OUT;CLEAR';
OPTIONS NODATE NONUMBER NOCENTER PS=54 LS=70;

********************************************************;
*** Cluster sample analysis for equal-sized clusters ***;
********************************************************;

DATA cluster1;
  M0 = 400;     * number of secondary sampling units (SSUs) in population;
  n  = 8;       * number of primary sampling units (PSUs) sampled;
  m  = 4;       * number of SSUs in a PSU;

  wgt = M0/(n*m);
  DO psu = 1 to n;
  DO ssu = 1 to m;
     INPUT trees @@; OUTPUT;
  END; END;
DATALINES;
1 2 4 1   2 0 7 0   2 2 0 0   0 0 2 6
1 16 8 1  2 2 2 0   2 1 0 1   0 0 0 1
;

*** TOTAL = number of PSUs in the population ***;

PROC SURVEYMEANS DATA=cluster1 TOTAL=100 MEAN CLM SUM CLSUM;
     VAR trees;
     CLUSTER psu;
     WEIGHT wgt;
TITLE 'One-Stage Cluster Sample from Figure 8a';
RUN;