Are IPUMS-USA samples are nationally representative, and are they also representative of smaller areas?
IPUMS-USA samples are nationally representative. IPUMS-USA data can be considered representative of geographic areas of all sizes, as long as the proper weights are applied. The standard errors of statistics based on smaller geographic areas will be larger than those based on national data, but this is due only to the reduced sample size rather than to the fact that one is analyzing a small area.