The intergenerational structure of the data and linking methodology is outlined here. This page describes LIFE-M's variables and sample sizes.

LIFE-M Variables

For individuals born in Ohio and North Carolina from 1900 to 1930 (generation 2), LIFE-M's variables include:

LIFE-M's Sample Sizes

LIFE-M includes very large samples of Americans relative to other available historical data, especially for women and under-represented minorities.

Women can be linked, because vital records typically contain information on women's birth and married names. Census linking projects based on surnames necessarily exclude women who change their names at marriage. Birth certificates contain information on mothers' birth names in the majority of cases. While coverage is incomplete, marriage certificates contain information on the birth names of the bride and groom. This information provides a cross-walk between women's names that facilitates the inclusion of this group. Although many historical longitudinal samples exclude women by necessity (e.g. the Union Army veterans) or because they cannot be linked by last name (Census-Census linking), LIFE-M will follow large, representative samples of women longitudinally and across generations.