surveyoptions: Options for the survey package
Description
This help page documents the options that control the behaviour of
the survey package.Details
All the options for the survey package have names beginning with
"survey". Three of them control standard error estimation.
When options("survey.ultimate.cluster") is TRUE,
standard error estimation is based on independence of PSUs at the
first stage of sampling, without using any information about
subsequent stages. When FALSE, finite population corrections
and variances are estimated recursively. See svyrecvar
for more information. This option makes no difference unless
first-stage finite population corrections are specified, in which
case setting the option to TRUE gives the wrong answer for a
multistage study. The only reason to use TRUE is for
compatibility with other software that gives the wrong answer.
Handling of strata with a single PSU that are not certainty PSUs is
controlled by options("survey.lonely.psu"). The default
setting is "fail", which gives an error. Use "remove"
to ignore that PSU for variance computation, "adjust" to
center the stratum at the population mean rather than the stratum
mean, and "average" to replace the variance contribution of
the stratum by the average variance contribution across strata.
The variance formulas for domain estimation give well-defined,
positive results when a stratum contains only one PSU with
observations in the domain, but are not unbiased. If
options("survey.adjust.domain.lonely") is TRUE and
options("survey.lonely.psu") is "average" or
"adjust" the same adjustment for lonely PSUs will be used
within a domain. Note that this adjustment is not available for
replicate-weight designs, nor (currently) for raked,
post-stratified, or calibrated designs.
The fourth option is options("survey.want.obsolete"). This
controls the warnings about using the deprecated pre-2.9.0 survey
design objects.