st: confidence intervals for means and ratios using p-weights in SRS

[Henrique Dantas Neder <hdneder@ufu.br>]

Dear all

I want to estimate confidence intervals starting from data that come 
from a systematic sample. For this I intend to consider this sample as 
approximately SRS (Simple Random Sampling). The sample is weighted with 
weights of the type p-weight. I cannot use the command ci to calculate 
confidence intervals for populacion means, because this command doesn't 
admit p-weights. How should I proceed? 
I also want to estimate ratios  (for example x/y, were x is the number 
of unemployed people and y is the total number of persons that are 
employed and that are looking for a job). I tried to use the command 
svyratio but I am in doubt if this serves automatically when I am not 
using cluster sample and I only specify in the svyset the weight as 
pweight and I don't specify the variables PSU and STRATA. How should I 
proceed to estimate a relationship (x/y) when do I have a sample SRS or 
a systematic sample? 
 Thanks in advance

Henrique Neder
Universidade Federal de Uberlandia - Brazil

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