Income sources are government transfers, maternal and paternal income, and unearned income. We aggregate these to total income or, if the survey already supplies a total household income variable, we harmonize that. Asset indices are also generated with principal component analysis. This folder contains tables with the loadings, which give an idea of what variables are available in each of the surveys.
Demographic variables are typical of those used as control variables. For example: sex, age, parental education, household structure, urban/rural.