Understanding Family Relationships

I. Definitions Used in Describing Individuals and Families in the House

II. Dealing with Different Definitions of "family"

III. Warning about "Family Level" data on the CPS and in TRIM3

IV. Aggregating Persons into Different Definitions of "Family"

V. SAS Example of Aggregating Persons within a Person Level Extract into Families, and Developing Summary Variables for Each Family

VI. Family Relationship: head, spouse, child (by definition of family)

A number of terms are used in describing the individuals and families making up a household. To really understand household data, the analyst should become familiar with the terms below.

Household Reference Person - The person in whose name the house is owned or rented. If a married couple, then either the husband or wife may be designated the household reference person. The CPS keys all family relationship information to the household reference person, sometimes referred to as the Householder. ExpandedRelationship should be used to identify household reference persons, since HhFamilyRelation and DetailedHhFamilyRelation do not identify household reference persons in group quarters households.

Family Householder - The household reference person, if he or she has at least one relative by birth, marriage, or adoption living in the household.

Nonfamily Householder - The household reference person, if he or she has no relatives living in the household. Also referred to as a Primary Individual, or loosely as an Unrelated Individual.

Primary Family -The family containing the family householder, consisting of all persons related to the family householder by birth, marriage, or adoption. Related subfamilies (see below) may be included with or excluded from the primary family, as described in section II.

Related Subfamily - A married couple with or without children, or one parent with one or more own never married children under 18 years old, living in a household and related to, but not including, the household reference person or spouse. For example, a young married couple sharing the home of the husband=s or wife=s parents. Prior to the March 1980 CPS, related subfamilies were referred to simply as subfamilies.

Unrelated Subfamily - A married couple with or without children, or one parent with one or more own never married children under 18 years old, that does not include anyone related to the household reference person or his or her relatives. For example, guests, roomers, boarders, or resident employees and their families living in the household. Prior to the March 1980 CPS, unrelated subfamilies were referred to as secondary families.

Unrelated Individual - A person who is not the household reference person and is not related to anyone else in the household. Some unrelated individuals are actually related to other people in the household, but (beginning with the March 1989 CPS) this relationship is not captured. Types of relationships among persons unrelated to the household reference person that are not reflected in the unrelated subfamily definition are lost. For example, if two brothers are living in a household, but are not related to the household reference person, the CPS does not indicate that they are related. Each brother would be counted as an unrelated individual. Prior to the March 1980 CPS, unrelated individuals were referred to as secondary individuals. Loosely applied, the term may include nonfamily householders.

Group Quarters - Noninstitutional living arrangements for groups not living in conventional housing units or groups living in housing units containing nine or more persons unrelated to the designated household reference person.

There are two basic definitions of family used in tabulating TRIM3 results: family with subfamilies included, and family with subfamilies separate.

This definition of family incorporates all related persons in the household into a single family. So a three generation family including grandparents, their adult daughter, and her child would be one family. Unrelated subfamilies are maintained as separate families.

Under this definition, both related and unrelated subfamilies are counted as separate families. In the three generation example above, the adult daughter and her child would constitute a separate family.

Although they are not technically families, in that they have no relatives, primary and unrelated individuals are always represented as separate families in TRIM3. The one exception to this rule is that TRIM3 does not permit unrelated children under the age of 15 to be in a family by themselves (prior to the March 1980 CPS, children aged 14 were permitted to be separate families, but those younger than 14 were not). In TRIM3, these children are merged into the family of the (family or nonfamily) householder.

The Census does not always include primary and unrelated individuals in its counts of families. Analysts should consider whether to include or exclude primary and unrelated individuals from their counts of families.

Family level data from the CPS is available in TRIM3, but should be used with extreme caution. The CPS (and TRIM3) stores separate family level information for each primary family, related subfamily, unrelated subfamily, primary individual, and unrelated individual. What is not always clear is whether the family level information stored for the primary family is based upon information that includes or excludes its related subfamilies. Similarly, it is not always clear whether the family level information stored with the related subfamily reflects the subfamily alone, or the primary family including all of its related subfamilies. Analysts using a family level variable should be certain of what family concept is reflected in the variable. We recommend avoiding this source of confusion by aggregating person level information to the family level, as described in sections IV and V.

The TRIM3 person variables FamiliesWithSubfamilies and FamiliesSubfamiliesSeparate indicate which family a person belongs to, under the two different definitions of family. These variables are found in the Identification/Weight category of the Person table in the TRIM3 database. Each value has four digits, in which the two left digits serve as the family id.

Dividing FamiliesWithSubfamilies by 100, and truncating the result, yields values of 1, 2, 3.... for the first, second, third, etc family or unrelated individual within the household, with related subfamilies included in the primary family.

Dividing FamiliesSubfamiliesSeparate by 100, and truncating the result, yields values of 1, 2, 3.. for the first, second, third etc family or unrelated individual within the household, with related subfamilies counted as separate families.

For example: consider a household containing grandparents, their daughter and her child, and the daughter=s boyfriend (an unrelated individual). Under the FamiliesWithSubfamilies definition, there are two families in the household--the boyfriend constitutes a separate family, and the daughter and her child are included in the same family as her parents. Under the FamiliesSubfamiliesSeparate definition, there are three families. Grandpa and grandma are one family, the daughter and her child are the second family, and the boyfriend is the third family.

V. SAS Example of Aggregating Persons within a Person Level Extract into Families, and Developing Summary Variables for Each Family.

Below is an example of SAS code in which a person level extract has been made from TRIM3 using the view and export microdata tool, and the goal is to aggregate persons into families, and create summary tables describing the families. Note that the code uses the 8 character TRIM2 names suggested as SAS variable names by the TRIM3 export procedure.

* 1) Read in the TRIM3 person level extract, create a family id variable using flgut3 (FamiliesSubfamiliesSeparate--for families with related subfamilies separate) or flgut1 (FamiliesWithSubfamilies--for families including their related subfamilies). In either case, unrelated families and unrelated individuals are considered separate families;

Data Temp;

Infile; /* put infile statement here */

Input; /* put input statement here */

Famid=int(flgut3/100); /* creates a family id variable, with families and unrelated individuals

consecutively numbered within household --in this example the family id is

based on families with subfamilies separate, replace flgut3 with flgut1

* 2) Sort the data by household id, family id, and person id;

Proc Sort data=temp;

by hhid famid perid;

*3) Create a dataset containing one record for each family (as defined above). Sum income variables and record family characteristics in the new dataset;

Data Family (keep=hhid famid Faminc NumPer EldHead Weight);

Set Temp;

By hhid famid perid;

Retain Faminc NumPer Eldhead Weight; /* necessary to retain any variable being aggregated for the family, or recorded from the head of the family */

if first.famid then do; /* first record for this family, initialize variables for this family to zero */

Faminc=0;

Numper=0;

Weight=pswght; /* record the person weight for the family reference person--the first person in the family */

If age ge 65 then eldhead=1; /* flag the family as having an elderly head if the first person is ge 65 */

Else eldhead=0;

end;

Faminc = Faminc + Income Variables for this person;

Numper=Numper+1; /* increment number of persons by 1 */

if last.famid then output family; /* output one record for each family */

*4) Can then do tables using Family dataset;

In tabulating TRIM3 results, we must often identify the family head, family spouse, and whether there are children present (according to some definition of child). The TRIM3 HhFamilyRelation variable provides information necessary for this identification, but must be interpreted differently depending on the family concept being tabulated--families with subfamilies included, or families with subfamilies separate. Below is a guide for working with HhFamilyRelation in the context of these two family definitions.

If all that is necessary is to identify the family head, that can be done by identifying the first person in the family--the person with the lowest perid in the family being processed-- as illustrated in the SAS example above.

The exact definition of child will vary with the analysis being performed. Typically, a child is anyone who meets the definition of Own Child or Other Child below.

Own Child = own child <18

Potential Own Child = own child, if meet some broader age and/or student definition

Other Child = other child <18

Potential Other Child = other child, if meet some broader age and/or student definition

Note: these designations are made regardless of marital status, some definitions of child may exclude currently married or ever-married individuals. HhFamilyRelation indicates if the person is ever-married, so can be used to create a narrower definition of child.

Following Codes are for Children of the Family Householder

Following Codes are for Other Relatives of the Family Householder

Following Codes are for Unrelated Subfamilies

Following Codes are for Unrelated Individuals (who don't have any relatives in household)

When matching up head/spouse couples, remember that for each person identified as a spouse, there should be one (and only one) person identified as a reference person (i.e. head) in the spouse's family (family defined using FamilyWithSubfamiliesSeparate). Those two people define the couple. The following table shows which reference person codes can be coupled with each spouse code:

Spouse Code	Reference Person (i.e. head) code
2	1
6 or 11	17 or 22
18 or 23	5 or 10
26	25