Hello,
I want to estimate employment by industry by state using the 1970 census. Should I use data from the form 1 1% state sample or form 2 1% state sample? Estimates differ substantially depending on which form. Am I right in using form 2 as it is based on a population 15% sample?
Thank you!
While form 2 was administered to 15% of the population, the IPUMS form 2 state sample only includes records for 1% of the US population (the same as the other 1970 samples). The decision of which form to use depends on the variables that you require since each form contains variables that are not available in the other.
Without seeing your exact estimates, I’m unsure of how substantially your estimates differ. However, given the large number of industries identified in the data and the relatively small sampling density, I’m not surprised that sampling error could result in significant differences in your estimates. If individual-level microdata is not essential for your research, then I recommend taking a look at the geographically aggregated summary statistics on our spatial data project, IPUMS NHGIS. The project distributes published summary data tables from decennial censuses that are derived from the Census Bureau’s full count file. By filtering to 1970 (year) and occupation and industry (topics) in the data finder tool, you should be able to find table NT62A which provides counts of the population across 41 industries by state (as well as many smaller areas). We recommend that new users familiarize themselves with the website by viewing the short video tutorials on our user guide as well as relevant portions of the FAQ page.