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SAS FAQ 
How do I analyze survey data with a one-stage cluster design?

This example is taken from Levy and Lemeshow's Sampling of Populations.

page 250 simple one-stage cluster sampling
This example uses the tab9_1c data set.
NOTE:  The n = 5 in the proc surveymeans statement indicates that there were 5 PSUs from which the sample could be drawn.  You can use this option in any non-stratified design or in a stratified design in which the total number is equal in all strata, e.g. each strata has 20 elements from which the sample can be drawn.  The total is used to calculate the fpc; hence, if the total is omitted, an fpc will not be calculated.  The SAS keywords sum and mean are used to modify the output.

proc surveymeans data = tab9_1c n = 5 sum mean;
  weight wt1;
  cluster devlpmnt;
  var nge65 nvstnrs hhneedvn;
run;
The SURVEYMEANS Procedure

            Data Summary

Number of Clusters                 2
Number of Observations            40
Sum of Weights                   100

                               Statistics

                               Std Error
Variable            Mean         of Mean             Sum         Std Dev
------------------------------------------------------------------------
NGE65           1.675000        0.019365      167.500000        1.936492
NVSTNRS         0.575000        0.019365       57.500000        1.936492
HHNEEDVN        0.525000        0.019365       52.500000        1.936492
------------------------------------------------------------------------

This example is taken from Lehtonen and Pahkinen's Practical Methods for Design and Analysis of Complex Surveys.

page 83 Table 3.6  Estimates from a one-stage CLU sample (n = 8); the Province'91 population.
NOTE:  The r = .25 in the proc surveymeans statement indicates that the sampling rate was .25.  You can use this option in any non-stratified design or in a stratified design in which the sampling rate was the same in each strata.  The rate is used to calculate the fpc; hence, if the total is omitted, an fpc will not be calculated.  The SAS keywords sum and std are used to modify the output.

data page83;
  input id str clu wt ue91 lab91;
  fpc = 32;
  cards;
  1 1 2 4 666 6016 
  2 1 2 4 528 3818 
  3 1 2 4 760 5919 
  4 1 2 4 187 1448 
  5 1 8 4 129 927 
  6 1 8 4 128 819 
  7 1 8 4 331 2543 
  8 1 8 4 568 4011 
  ;
run;
proc surveymeans data = page83 r = .25 sum std ;
  weight wt;
  strata str;
  cluster clu;
  var ue91 lab91;
run;
The SURVEYMEANS Procedure

            Data Summary

Number of Strata                   1
Number of Clusters                 2
Number of Observations             8
Sum of Weights                    32

               Statistics

Variable             Sum         Std Dev
----------------------------------------
ue91               13188     3412.140091
lab91             102004           30834
----------------------------------------

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