Family Relationships in Mexican Censuses: A Proposal for an International Integration of Census Microdata and a Historical Overview

This paper studies family and household context of individuals over the life-course, using historical census microdata from the 16th and 18th centuries and integrated census microdata for 1970, 1990 and 2000. Integrated microdata are becoming readily available for many countries, thanks to a new openness by statistical agencies and to various national, regional, and international integration projects. As the data become more usable, they must be calibrated, if they are to be used well. In the case of Mexican censuses, family relationships are seemingly well-defined and comparable since the 1960s. Nevertheless, analyis of the census microdata suggests that researchers should approach these data with caution in their use and interpretation. The 1960 sample is of individuals, not households. Studying individuals in their household contexts (e.g., characteristics of household heads, mothers, fathers or spouses) is impossible. Likewise computing household statistics to attach to individuals is also impossible. The 1970 census microdata are seemingly comparable, as far as the explicit documentation is concerned. However, for the first time, a pre-coded form was used, and no allowance was made for multiple families in a single household. Therefore family relationships refer to conyugal family units, not households. Dwellings with multiple families have multiple heads, and the relationship to the household head went unrecorded. Nevertheless, multiple families households can be distinguished. The 1990 and 2000 censuses followed the more conventional methodology, in terms of the definitions of dwellings, households, families and relationships. For the 1990 census 86 distinct relationships to head are coded into the microdata, and families are clearly distinguished within households. In 2000, only 51 relationships were coded into the data, and the terminology between household (hogar) and families (familia in 1990) are not as clearly identified. For the 2000 census microdata researchers are cautioned to apply weights (factor de ponderacin) supplied by the Mexican statistical office (INEGI) and included with the IPUMS-International microdata. INEGI statisticians used a stratified cluster design so that processing of a 10% sample (10 million person records) could be completed in scarcely more than a year, compared with several years for earlier censuses. The bulk of the paper then applies the life course perspective to 16th, 18th and 20th century censuses, using the individual as the unit of analysis.