This example is taken from Lehtonen and Pahkinen’s Practical Methods for Design and Analysis of Complex Surveys.
page 60 Table 2.8 Estimates under a PPSSYS design (n = 8); the Province’91 population. NOTE: The certainty PSU (the first line of the data) was entered twice and the weight was changed from 1 to .5 for each observation. This is necessary because you need to have two observations in each strata.
data page60; input id str clu wt hou85 ue91 lab91; fpc = 32; datalines; 1 2 1 0.5 26881 4123 33786 2 2 1 0.5 26881 4123 33786 3 1 10 1.004 9230 1623 13727 4 1 4 1.893 4896 760 5919 5 1 7 2.173 4264 767 5823 6 1 32 2.971 3119 568 4011 7 1 26 4.762 1946 331 2543 8 1 18 6.335 1463 187 1448 9 1 13 13.730 675 129 927 ; run; proc sort data = page60; by str; run; proc descript data = page60 filetype = sas design = wr total; weight wt; nest str; var ue91; run;
Number of observations read : 9 Weighted count : 34 Denominator degrees of freedom : 7 Variance Estimation Method: Taylor Series (WR) by: Variable, One. ----------------------------------------------------- | | | | Variable | | One | | | 1 | ----------------------------------------------------- | | | | | UE91 | Sample Size | 9 | | | Weighted Size | 33.87 | | | Total | 15077.43 | | | SE Total | 521.12 | | | Mean | 445.18 | | | SE Mean | 150.47 | -----------------------------------------------------
NOTE: Use the setenv statement to set the decwidth to 5 to show the decimal to five places so that you can see that the standard error is correct. If you do not use the setenv decwidth = 5 statement, it appears that the standard error is .00.
proc ratio data = page60 filetype = sas design = wr; weight wt; nest str; numer ue91; denom lab91; setenv colwidth = 20; setenv decwidth = 5; run;
Number of observations read : 9 Weighted count : 34 Denominator degrees of freedom : 7 Variance Estimation Method: Taylor Series (WR) by: Variable, One. ------------------------------------------------------------- | | | | Variable | | One | | | 1 | ------------------------------------------------------------- | | | | | UE91/LAB91 | Sample Size | 9.00000 | | | Weighted Size | 33.86800 | | | Weighted X-Sum | 117353.19100 | | | Weighted Y-Sum | 15077.42800 | | | Ratio Est. | 0.12848 | | | SE Ratio | 0.00222 | -------------------------------------------------------------
proc descript data = page60 filetype = sas design = wr; weight wt; nest str; var ue91; percentile / median; run;
Number of observations read : 9 Weighted count : 34 Denominator degrees of freedom : 7 Variance Estimation Method: Taylor Series (WR) by: Variable, One, Percentiles. for: Variable = UE91. ----------------------------------------------------------------------------------- One Sample Weighted Lower 95% Upper 95% Percentiles Size Size Quantile Limit Limit ----------------------------------------------------------------------------------- 1 50.00 9 33.87 158.33 . 527.82 ----------------------------------------------------------------------------------- --------------------------------- One SE Percentiles Quantile --------------------------------- 1 50.00 . ---------------------------------