Dear Statalisters,
This question was left without an answer in August and I consider it
important enough to
post it again in case any of the people that could answer it were on holidays:
Following the discussion in the thread 'st: Chi square test
unavailable when subpop is used
in svy analyisis', I come to the understanding that the exclusion of
individuals with missing
values from the calculation of variance estimates with 'svy: prop
variable' and 'svy if variable==valid values: prop variable' is like,
for example, dropping men when you need estimates only for women
(using 'if' instead of 'subpop'), what is incorrect in survey
analysis.
Therefore, when calculating variances for valid values in a survey
variable (the rest of the values being missing either because the
respondent didn't answer, didn�t know the answer
or the question was not applicable), 'svy, subpop(valid values): prop
variable' should be
used, because it takes into account all individuals (with valid and
missing values) in the calculation. Is that correct?
Many thanks,
�ngel Rodr�guez-Laso
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