ACS Data Users Group

Hi. I'm preparing to run a probit regression in Stata using ACS PUMS data.

Does anyone have experience using the Stata svyset command (or, more generally, specifying relevant survey design factors in a statistical analysis program) with PUMS files?

The following is suggested for Current Population Survey analyses (see https://www.stata.com/statalist/archive/2008-04/msg00444.html), which uses state (gestcen) and consolidated statistical area (gtcsa) variables.

egen psu=group(gestcen gtcsa) svyset [pw=mars], strat(gestcen) psu(psu)

Does anyone have an analogous specification for PUMS?

Hi Michele,

I've used the Stata svy commands to analyze survey data (CPS, SIPP, NHIS). The first step is to svyset the data so Stata knows the sample design.

svyset [pw=wgtp], sdr(wgtp1 - wgtp80) vce(sdr) mse

(This example uses the single year 2010 PUMS dataset, ss10hak. The weights used are household-level weights.)

After svysetting the data, you run the command using the svy: prefix, which passes along the options you defined above. Stata will execute this command using the full-sample weights and again for each set of replicate weights. There are two important things to note:

(1) Not all Stata commands can be run with the svy: prefix.

(2) If you want to limit your replicate analyses to a subset of the sample (for example, all persons aged 25-64 or all African Americans), you should not use if or in. Instead, use the subpop() option before the colon, as in

. gen byte age25_64 = age>=25 & age<=64
. svy, subpop(age25_64): command

• Note that you must first define the subpopulation with a dichotomous variable coded 0 for all cases that should be excluded from the analysis.

Here a some additional resources that may be helpful:

https://www.stata.com/manuals13/svysvyestimation.pdf

https://www.stata.com/manuals13/svysvysdr.pdf

https://usa.ipums.org/usa/repwt.shtml

http://www.cpc.unc.edu/research/tools/data_analysis/statatutorial/sample_surveys/svy_commands/

https://stats.idre.ucla.edu/other/mult-pkg/faq/sample-setups-for-commonly-used-survey-data-sets/

Applying Occam's razor to the -subpop- option, you can just as well run

svy, subpop( if inrange(age,25,64) ): command

Also, I believe you can get versions of the ACS data off IPUMS that have strata and cluster/PSU variables. It is easier to deal with these -- or at least the commands run faster. I have not compared the standard errors produced one way vs. the other, but I would not expect to see huge differences.

Hi Amanda,

Thanks so much! This is exactly what I needed.

Michele

Hi Stas,

Thank you very much! This is extremely helpful. I'm grateful for your assistance.

Michele