0 = N.I.U. (Not in Universe; Zero siblings).
9 = 9 or more siblings (Topcode).
NSIBS counts the number of own siblings (including half-siblings, step-siblings, and adopted siblings) residing with each individual. Persons with no siblings present are coded 0.
Note that NSIBS is an IPUMS-derived variable using IPUMS-derived family interrelationships. Thus NSIBS may differ from any family information that comes from the ATUS.
The comparability of this variable is affected by the information available on family relationships. NSIBS is based on the information contained in RELATE (Relationship to household head), MOMLOC, MOMLOC2, POPLOC, and POPLOC2. These variables are comparable from 2003 onward.
Comparability with IPUMS-USA
The development of new family interrelationship variables was prompted by the desire to have more comparability between different IPUMS projects and over time. The family interrelationship variables use common logic across ATUS-X, IPUMS CPS, IHIS, and USA (modern years). Each project has different allowed links because of different level of detail in each project, but the logic of assigning parents in ambiguous situations is the same.
- ATUS respondent household members.