CenSoc-Numident

The CenSoc-Numident dataset links the 1940 census to the National Archives’ public release of the Social Security Numident file (“NARA Numident”). Our linking strategy relies on first name, last name, year of birth, and place of birth. To link unmarried women, we use father’s last name as a proxy for women’s maiden name. We use the ABE fully automated linking approach developed by Abramitzky, Boustan, and Eriksson (2012, 2014, 2017). To work with this dataset, researchers must download and link the 1940 full-count Census sample from IPUMS-USA on the HISTID variable. Please adhere to the citation and usage guidelines of both CenSoc and IPUMS-USA when using this dataset. The CenSoc-Numident supplemental geography file contains additional variables with place of birth and/or place of death information, such as county of birth and death, for a subset of the CenSoc-Numident dataset.