I am using IPUMS International to look into local labour markets. Will the weighting variable PERWT make a given sample representative for the national level or also on the regional level? I.e. if I weight all observations from region X by PERWT and then compute statistics are they representative of that region?
The sampling procedure by which IPUMS-International samples are drawn creates an implicit geographic stratification which makes the samples representative at sub-national levels. I would recommend reading through the Sampling Error and Variance Estimation for a more complete discussion of the subject.
I hope this helps.