Re: st: strata with single sampling units

[sjsamuels@gmail.com]

" Would I be safe in assuming that one would use weight and PSU, and ignore
strata in this case? "

No. Do not ignore the stratum specification.  By placing certainty
units in their unique strata you ensure that they contribute nothing
to the between-PSU component of variance.  If the purpose of your
study is to describe the population, then the first stage fpc for the
certainty units should be 1.

Steve Samuels
sjsamuels@gmail.com
18 Cantine's Island
Saugerties NY 12477
USA
845-246-0774



> When I went back to the documentation it is stated that the study
> used a multistage stratified design in which primary sampling units
> (PSUs) were stratified according to certain sociodemographic criteria. The
> sampling
> frame for housing units is the Census 2000/2001 Supplementary Survey
> (C2SS) and that
> for group quarters is the Census 2000 Group Quarters Inventory. The C2SS
> sample of
> 655 PSUs was selected at the first stage, including 401 self-representing
> (SR) and 254
> non-self-representing (NSR) PSUs. All SR PSUs were selected with
> certainty. For the
> NSR sample, two PSUs were selected per stratum, with probability
> proportional to the
> size of the estimated 1996 population of the stratum.  NOTE: Sample was
> included from each of the 655 PSUs.
> However, to prevent potential respondent disclosure, some PSUs were
> collapsed so that the final
> data file shows 435 PSUs, 305 being SR and 130 being NSR.
>
> So there are 305 strata with one PSU.  Final sample is 43,093.
>
> Would I be safe in assuming that one would use weight and PSU, and ignore
> strata in this case?  No other design variables are provided.  Doing
> things this way seems to replicate SEs in the published tables  -- at
> least the few I tried to replicate.

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