NLSY79

Sexual activity

In 1982, 1983, 1984, and 1985 NLSY79 respondents were asked about their sexual activity. Once the respondent answered the questions, he or she was not asked the series in subsequent surveys. Out of a total of 12,686 respondents, 310 did not answer any of the questions in these years.

The first activity question asked respondents whether they had ever had sexual intercourse. This question was skipped if the respondent had previously reported either being a parent or being pregnant. Out of the 11,797 respondents, 889 or 7.5 percent stated that they had never had sexual intercourse. The youngest respondents answered this question when they were 18. The validity of these items is evaluated in Mott (1985). These data should be used cautiously because inconsistencies in reports of first intercourse with subsequent fertility events can sometimes occur. Respondents who had ever engaged in sex were then asked at what age they first had intercourse. Table 1 includes frequencies broken down by race and sex, as well as a total for the whole cohort.

Questions in this section also ask NLSY79 respondents if they have had sex in the past month. In 1983, respondents provided a yes/no answer. However, in 1984 and 1985 they were asked the number of times they had sex in the last month. The data contain some outlying entries; users should carefully decide how to interpret outlying data points in these distributions. Additionally, there is evidence of a significant number of youth who changed their "ever had sex" status from yes to no between 1983 and subsequent survey years.

In 1984, the survey also asked if respondents had taken a sex education course. If so, they were asked at what date they took the course. Respondents also stated whether the first course they took covered:

• The female menstrual cycle
• Contraception methods
• Where to obtain contraception
• Effects of contraception
• Sexual diseases

To test reproductive knowledge, respondents were also asked (Table 2) when pregnancy is most likely to occur during the female monthly menstrual cycle. Answers in 1984 show a substantial portion of respondents did not choose the medically correct answer of about two weeks after the period. Approximately 25 percent of men and 12 percent of women stated they did not know the answer.

Contraception

Since 1982, NLSY79 respondents have regularly been asked about their use of contraception. These contraception questions appear in the "Fertility" section of the questionnaire. The questions were asked annually from 1982 to 1986. After 1986 the questions were asked only in even years corresponding with the child supplements. After 1994, the surveys became biennial and the questions were included in each survey.

The respondents are asked if they use birth control. If they state that they do, the second question asks the frequency of these methods using a three-point scale of "always," "sometimes," or "almost never." Finally, respondents are asked to state all the methods they have used in the past month from the following list:

• Pill
• Condom, rubber
• Foam
• Jelly or cream alone
• Suppository or insert
• Diaphragm with or without jelly or cream
• Douching after intercourse
• IUD, coil, loop
• Operation-Female sterilization, tubes tied
• Operation-Male sterilization, vasectomy
• Natural family planning, safe period by temperature and cervical mucus test
• Rhythm or safe period by calendar
• Withdrawal/pulling out
• Contraceptive sponge
• Other method

Over time the list has been expanded and now includes four additional choices:

• Abstinence
• Norplant
• Cervical cap
• Depo-Provera
• Hysterectomy

Beginning in 2002 a specific individual question was added asking respondents if they have been surgically sterilized. If they have been sterilized they will not be asked this series of birth control questions again. Previously, sterilization was an option among a list of birth control options (see list above), but it was not a separate question.

In most years, at the end of this three-question series, the interviewer fills in a question that states if anyone else was present during this part of the questioning. Small children under three years old are not counted by interviewers when filling in their response.

In addition to these questions, female respondents who are pregnant or who have given birth since the last survey year are asked about their contraception methods before conceiving. Respondents are asked if before becoming pregnant they used one of the birth control methods listed, or if they stopped all birth control methods before becoming pregnant. Finally, they were asked if the reason they stopped using birth control was because they wanted to become pregnant.

Reference

Mott, Frank L. "Evaluation of Fertility Data and Preliminary Analytical Results from the 1983 (Round 5) Survey of the National Longitudinal Surveys of Work Experience of Youth." Columbus, OH: CHRR, The Ohio State University, 1985.

Data on childcare have been collected within various topical sections of the NLSY79 questionnaires. The main data collection on types of childcare arrangements, discussed in detail below, occurred during the 1982-86, 1988, 1992, and 1994-2014 surveys. Starting with the 2016 survey, childcare data were no longer gathered, due to the age of the sample.

A range of both retrospective and cross-sectional (past four weeks) childcare information is available in the NLSY79. The mother-report child care sections from the NLSY79 provide the types of current childcare arrangements used for each child in the household, a retrospective of childcare experiences during the first three years of life for all children (of at least 1 year of age) born to the respondent, and in some survey years, the overall family expenditure for current care.

Retrospective

Retrospective data were gathered during the 1986, 1988, 1992 and 1994-2014 survey years for up to three childcare arrangements used by NLSY79 mothers for each of their children during the first three years of life. For each year, mothers were asked about whether the child lived with them and, if so, whether that child was in child care. If so, questions about specific child care arrangements during that year of the child's life were asked about. (While childcare information was not collected in the 1990 NLSY79 survey round, it was updated in 1992.)

The data about childcare in the first three years of life have been concatenated into cross-round variables that allow users to study the use of child care during each child's first 3 years of life. For each of the first three years of life for each child there is a variable indicating whether or not that child was in child care during their first year or why this information is unavailable (i.e., the child did not live with the mother, the child or the mother was deceased, the mother was part of a dropped sample type, etc.) If the child was in childcare for a given year, there are variables for up to 3 types of arrangements and the number of months spent in each arrangement.

Cross-sectional

Current childcare information was first asked in the 1982 survey about the youngest and next youngest child living in the mother’s household. In the 1983, 1984, and 1985 NLSY79 surveys, questions were asked about current child care arrangements used in the past four weeks for the youngest child by parents who were either employed, in school, or in training at the survey date. Location and type of primary and secondary care and hours of use were initially asked in 1983, and these questions were expanded in 1984 to include nature of payment and grandmother care. Location, type, payment, detail on group arrangements, and hypothetical care are available for 1985. In both 1984 and 1985, respondents who are not currently employed but who have an employed spouse report limited information on location and type of care.

In both 1986 and 1988, NLSY79 mothers are asked a limited number of questions about current child care arrangements for all of their children living in the household.

The retrospective information collected in 1986 and the current child care information collected between 1984 and 1988 relate to different universes of children and utilize different child care definitions. Additional child care information was also collected in the 1982 and 1983 NLSY79 surveys.

There are marked differences in the universes of respondents, reference children, kinds of questions asked, and reference periods across survey years (see Table 1 below). Universes of respondents vary widely both within and across survey years, from respondents--both male and female--engaged in some educational or labor market pursuit, to all women with a child in the household, to not-employed respondents with an employed spouse. The focus during the initial survey years was on collecting information on childcare arrangements used over the past month for only the youngest child(ren) in the household.

• A limited number of childcare questions, fielded within the 1987, 1989, and 1990 fertility series, obtained information from select universes on:
  • Whether respondents made use of regular childcare arrangement
  • Whether respondents encountered childcare problems that affected their employment
  • The extent of responsibility for childcare assumed by female respondents during recent pregnancies
• Out-of-the-labor-force respondents could specify within various sections of the yearly questionnaires, such as the 1980-98 "CPS or Current Labor Force Status" or 1979-2014, "Periods not Working" sections, that lack of available childcare or family responsibilities was a reason they were not looking for work or did not want a job now

In addition, information on whether childcare services were provided as a supportive service through Federally funded government employment and training programs was gathered during the 1979-87 surveys. For those respondents residing in households with children under age 14, the special 1981 "Household Chore and Childcare" time use survey provides information on the amount of responsibility for providing childcare at home and actual time spent on a given day in specific childcare tasks. The Fringe Benefits section of this guide details the collection of information on childcare as a benefit made available by employers of NLSY79 respondents. Finally, a special experimental Childcare Supplement, administered to 347 NLSY79 mothers who were interviewed during the first month of the 1989 fielding, collected a wide range of information, including data on every childcare arrangement used for at least 10 hours per week since the date of last interview. Researchers interested in the 1989 special childcare supplement data should contact NLS User Services. A report evaluating the quality of various childcare data items is available from CHRR (Mott and Baker 1992).

Types and locations of childcare arrangements

Data on types and locations of childcare arrangements are available for the 1982-86, 1988, 1992, and 1994-2014 survey years. Typical categories of childcare arrangements include self-care; care by relatives (the child's other parent, a step-parent, siblings, or grandparents); care by nonrelatives; and care provided by institutions such as day care centers, nurseries, or preschools. Information on care provided by individuals usually differentiates between that occurring in the child's home and that occurring in another private home. Information was gathered during select survey years (1983-86 and 1988) on both primary and secondary childcare arrangements.

Additional characteristics of childcare arrangements

In addition, supplementary information has been collected during certain survey years on the number of hours that childcare services were required/provided, the nature of the payments (cash or noncash), total cost per child/per provider, and the effect of available childcare services on such activities as employment, job search, and training.

References

Mott, Frank L. and Baker, Paula. "Evaluation of the 1989 Child Care Supplement in the National Longitudinal Surveys of Youth." Discussion Paper 92-6. Washington, DC: U.S. Department of Labor, Bureau of Labor Statistics.

Marital status

Marital status information for NLSY79 respondents is available from:

• responses to questions fielded during the annual or biennial surveys
• two sets of created variables specifying marital status as of the interview date
• an item on the marital status of each respondent as of the previous interview derived from the interviewing aid called the Information Sheet

Marital history/transitions

A series of edited Supplemental Fertility File variables (area of interest "Fertility and Relationship History/Created") that reflects the beginning and ending dates of marriages was constructed for all marriages through the present. These variables include the month and year the respondent began a marriage and the month and year a marriage ended, for example, 'Month Began 1^st Marriage.' The unedited data items include the month and year of each reported marital transition and type of transition. Users should note that a separate category for the transition to "reunited" was not added until the 1981 survey. Evaluations of the marital history data for the NLSY79 can be found in Haurin (1988, 1994). A related variable, also located in the "Fertility and Relationship History/Created" area of interest, provides the number of months between the respondent's first marriage and the birth of the respondent's first child.

Cohabitation

The following cohabitation information is available from the 1990 and 1992-2016 surveys:

• the month and year the respondent and his or her opposite-sex partner began living together
• whether the respondent lived with his or her spouse before marriage
• the month and year the respondent and his or her spouse began living together
• whether the respondent and his or her spouse lived together continuously until marriage

A household member's relationship to the respondent may be listed as "partner" in the Household Record. This is true regardless of whether the "partner" is of the same or opposite sex as the respondent. However, through 1996 only opposite-sex partners are referenced during the interview for questions relating to household, income, and dating/relationship. After 1998 information on all partners is collected.

Beginning in 2002, respondents were asked detailed questions about their cohabitation experiences during any unmarried spell lasting three months or longer. First, respondents were asked about marital status and changes in marital status. If any unmarried gap lasting three months or more was identified, respondents were asked if they ever lived with anyone as a domestic partner for three months or more since the last interview. If respondents answered affirmatively, they were then asked specifically about each unmarried gap of three months or greater.

For each unmarried gap, respondents were asked the following series of questions: First, respondents were reminded of the marital status they reported during the gap and asked if they lived with someone as a domestic partner during that period. If a partner was reported, respondents provided information on the date on which they began cohabiting, whether they cohabited with this partner continuously until the current interview date and, if not, the date they stopped cohabiting with this partner during the specific gap. After these questions were answered, the dates were compared. If the unaccounted-for remainder of the specific gap was three months or more, the respondent was asked if they lived with any other partner during that gap for three months or more. If the answer was "yes," the questions were repeated for the next partner during that gap. This entire series of questions was then repeated for each eligible three-month-plus unmarried gap.

Same-sex partners

Beginning in 2000, the question titled “IS THERE A SAME SEX PARTNER IN THE HOUSEHOLD?” (Q9-64FB) indicates a same-sex partner reported.

Prior to 2000, the questions on NLSY79 partners were limited to an opposite sex adult; however, it may be possible to find some same-sex partners prior to 2000 by looking at the Household Record variables. To do so, users can identify the household member who is the spouse or partner by using the relationship variables HHI_FINAL_RELCODE, then identify the sex for that same member# using HHI_FINAL_GENCODE.

Spousal characteristics

Information collected as part of the Household Record is available for spouses and partners at each survey point if they are listed as members of the household. Users first need to identify the appropriate relationship to the respondent (that is, code "1" for spouse; code "33" for partner) through variables that are specific for this purpose. Typically, information on the age, relationship to respondent, highest grade of schooling completed, and employment in the past calendar year is collected during each survey. See Household Composition for information on specific characteristics. In addition to information available from the Household Record, additional information has been collected on the spouse as part of the Marital History section of the questionnaire. Users should consult each relevant survey year's questionnaire or codebook to ascertain the specific items collected in the given year. Information on income has been selectively collected for the respondent's spouse or partner. Users should check the Income section for further details.

Marital attitudes and expectations

A series of relationship satisfaction questions were asked during the 1988, 1992, and 1994-2016 interviews of those mothers living with a spouse or opposite-sex partner. These questions dealt with both positive and negative interactions in the relationship, for example, 'Frequency R and Husband/Partner Calmly Discuss Something' and 'Frequency R and Husband/Partner Argue About - Money.' In addition, mothers without a spouse or partner were asked for information on 'Frequency R Goes Out on Dates,' whether the 'Oldest Child Encourage(s) R's Dating,' and 'Likelihood of Marriage in the Future.' In 1979, all never married respondents were asked for information on 'Age Expects to Marry.'

Environmental characteristic data

For the 1979-1982 interview years, the restricted-use Geocode file includes marriage and divorce rates and percent of families with female heads of household for the county and SMSA in which the respondent resided. These statistics are taken from the 1972 and 1977 County & City Data Books. From 1983 until 1998, marriage and divorce rates and the number of families with a female head are included for county of residence only, based on statistics from the 1983 and 1988 County & City Data Books. The 2000 release includes the same information based on statistics from the 1988 and 1994 County & City Data Books.

The following race and ethnicity variables are available for NLSY79 respondents: 

1. a racial/ethnic variable based on the sample identification code assigned by NORC
2. a series of self-reported ethnic origin variables collected during the 1979 and 2002 surveys
3. a set of interviewer identifications of the race of the respondent at the time of the interview
4. racial/ethnic identification for current and past spouse/partners
5. variables representing the respondent's immigration history and status collected during the 1990 survey
6. a 1979 variable indicating whether a foreign language was spoken in the house during the respondent's childhood
7. a series of variables recorded by the interviewer indicating whether the survey was administered in English or another language
8. race/ethnicity variables for each family member listed during the 1978 screener
9. race of the interviewer where available at each interview
10. country of origin of the respondent's parents and the respondent's country of birth, available on the restricted Geocode release

Race and ethnic origin information is also available for each household member identified during the 1978 household screening. In 2002 respondents were asked to identify their race/ethnicity using questions that conformed to Federal government definitions. Of related interest is a series of immigration questions, fielded in 1990, that included the collection of information on country of citizenship at the time that foreign-born respondents entered the U.S.

Race/ethnicity

The variable 'Racial/Ethnic Cohort from Screener' (R02147.) designates the respondent as "Hispanic," "black," or "nonblack/non-Hispanic" and provides the basis for weighting NLSY79 data. This variable is collapsed from R01736., 'Sample Identification Code,' which includes such values as "supplemental male black" or "cross-sectional female Hispanic." This code was assigned by NORC to each respondent based on information gathered during the 1978 household screening. In the creation of the 'Sample Identification Code' and thus the 'Racial/Ethnic Cohort' variable, both race and ethnic origin information collected at the time of the 1978 household screening were used. Interviewers conducting the screening were instructed to:

1. code race by observation into three categories, "nonblack/non-Hispanic," "black," or "other"
2. inquire about the ethnicity of all household members age 14 or above
3. but assign ethnicity, without asking, to those members who were under age 14

Coding procedures used by NORC to assign the "Hispanic," "black," and "nonblack/non-Hispanic" identifications to respondents included the following classification guidelines:

A series of ethnic identification variables, '1^st-6^th Racial/Ethnic Origin' and 'Racial/Ethnic Origin with Which R Identifies Most Closely' (R00096.-R00102.), provide extensive ethnicity information. Respondents were asked during the 1979 interviews to name the racial/ethnic origins with which they identified. A listing of more than 20 categories, including "Black," "English," "French," "German," "American Indian," "Irish," "Mexican," "Mexican-American," and "Puerto Rican," were presented on a Show Card. If a respondent offered more than one origin, he or she was also asked for the ethnic group with which he or she most closely identified. Users should be aware that frequency counts for the coding category "Indian American, or Native American are unusually high. About 5 percent of respondents reported this racial/ethnic origin, compared to Census estimates of approximately 0.5 percent of the population. This may have resulted from some respondents' misinterpretation of the term "Native American." Table 1 compares frequencies of the 1979 first (or most closely held) ethnic identification with the NORC assigned racial/ethnic identification.

Immigration

In 1990, NLSY79 respondents born outside the United States, its territories, or Puerto Rico were asked a series of questions on their immigration history and visa status. Dates of first and most recent entrance into the United States to live for six or more months and information on whether the respondent was the principal entrant/immigrant were collected. For respondents' or principal entrant/immigrants' first and most recent entry or change in visa/immigration status, details were gathered on:

1. visa or immigration status at entry date
2. form of temporary entry visa
3. citizenship status (that is, citizen or permanent resident alien) and relationship of the sponsoring relative
4. country of citizenship at entry date or date of change of status

Also recorded for the respondent was information on:

1. current citizenship/residence/visa status in the United States
2. residence inside/outside the United States
3. expectations to return to the United States to live permanently or to return to his or her country of birth to live permanently
4. the total number of years spent outside the United States since initial entry

Of related interest is the variable, 'Is R a Citizen of the U.S.' available from the 1984 and 1990 interviews.

Foreign language used or spoken

For each household member, information is available from the screener on presence of a Spanish surname and whether Spanish was the language spoken in the home when that individual was a child. The 1979 interview asked whether a foreign language (Spanish, French, German, other) was spoken at home during the respondent's childhood. In addition, interviews record for each survey whether English, Spanish, or another foreign language was used to administer the Household Interview Forms ('English or Foreign Language Used for Household Record') and questionnaire ('Int Remarks - Was Interview Conducted in English or Foreign Language').

Reference

NORC. 1978 Household Screener and Interviewer's Reference Manual. Chicago, IL: National Opinion Research Center - University of Chicago, 1978.

• This section describes variables related to household and family composition, household identification, linkages between members of multiple respondent households, and household residence.

Household members

The term "household" refers to all individuals sharing the respondent's primary residence at the time of the interview. For respondents living in temporary quarters (except temporary military quarters), the usual residence is defined as that person's permanent residence. For those living in their own dwelling unit or in military family housing, the usual residence is the person's dwelling unit. For example, if a male college student is living in a temporary residence, such as a fraternity, those who share his permanent residence, such as his parents' address, would be considered his household members. However, if that same college student were living in his own apartment, all those living in his apartment would be considered his household members.

Persons analyzing military households should note that household screener information was not collected for persons in the military sample. Thus, while military units are included in the total 8,770 unique households, military units cannot be multiple respondent households. Household specification for those respondents enlisted in the military is as follows:

1. for those in the military who are married but living in military quarters other than military family housing, the household is the household of the respondent's spouse, and
2. for those in the military who are unmarried, no household information is recorded.

During PAPI surveys, information about a respondent's household was gathered during a separately administered household interview. Three different Household Interview Forms "Household Interview Forms" were used prior to 1987: 

• Version A was completed by a parent of those respondents living in a parental household
• Version B was administered to youth not living at a permanent address
• and Version C was answered by those respondents living in their own dwelling unit or independent living quarters

Table 1 details, by survey year, the relevant universes and residence types specific to each version; notes on variations in administration of the forms are included. A series of variables entitled 'Version of Household Record Used' is available for the 1979-80 and 1982-86 survey years. To determine the version of the household interview used in 1981, it is necessary to match information from the variable, 'Type of Residence R is Living In,' to residence information that was included on the three different forms. Beginning in 1987, only one version of the household interview was used, as all respondents were 22 or older and living predominantly on their own. Since the introduction of CAPI interviews in 1993, household information has been collected in the first section of the main questionnaire rather than in a separate instrument.

All members of the respondent's household are enumerated each survey year on the household record; in 1978, household members were listed on the household screener. The relationship generally listed for each household member on the household record is relative to the youth respondent, such as 'Household Record - Relationship to Youth Member # 1.' For variables from the screener and for one series of 1979 household record variables, the relationship of household members (only family members in the screener) is relative to the householder. Anyone who lives in the residence but is temporarily away is listed; anyone who is there only temporarily is removed from the listing. For the screener and for interviews in which the respondent lives in a new household, that is, living with new people rather than living at a new address, the householder generally is listed first, followed by a spouse; any children; any other relatives; and any roomers, boarders, hired help, or other usual unrelated residents.

Family members

Within the listing of household members, family units are identified through family unit numbers and relationship codes. A family unit includes all those related by blood, marriage, or adoption. For each member of the household in every survey year, including the 1978 screener, the family unit number is listed on the "Household Enumeration" or the screener, such as 'Household Record - Family Unit # 1 Member # 1.' All family members in an interrelated group will share a family unit number, with number 1 assigned to the respondent's family. Each additional interrelated group or individual adult sharing the household but not related to another group or individual in the household constitutes an additional family unit. For example, if Mr. and Mrs. Brown are boarders in the same house with Mr. and Mrs. Smith, the Smiths are the first family unit and the Browns are a second family unit. The reliability of 1979-92 family unit numbers beyond those assigned to the respondent's family is questionable. Beginning in 1993, family units were assigned electronically; the definition of a family unit remains the same. Codes were added for partner's family/relations. All others are assigned a code of "9."

An enumeration of a respondent's children is also available. Several variables have been created as part of the Supplemental Fertility File (area of interest "Fertility and Relationship History/Created"), including variables such as '# of Own Children in Household,' 'Age of Youngest Child in Household,' and a variety of variables for each biological child listed, with some exceptions, in order of age. Unedited variables from the Children's Record Form (areas of interest "Child Record Form/Biological" and "Child Record Form/Nonbiological") are also available for both biological and nonbiological children. If there is a discrepancy between household rosters versus marriage event histories use the marriage event histories rather than the household roster data. See the "Fertility" section of this guide for more information about the collection of information on the respondent's children.

Additionally, information about household members includes, sex of the member, their relationship to the respondent, age, highest grade completed, and whether the member receives pay for work (age restrictions apply.)

Finally, information on whether the mother and father of each child (in 1991, new children only) live in the household is available for the 1987-2014 survey years. In all other years, information on whether the father of the child is present is available for children of female respondents.

Family size

Beginning with the 1990 release, a family size variable, comparable to the family size variable created for the computation of the 'Total Net Family Income' and 'Poverty Status' variables, was created for each year. The variable is constructed by simply cycling through the household record "relationship codes" and increasing the family size by one each time a qualifying relationship relative to the respondent is encountered. Qualifying relationships include all relations by blood, marriage, and adoption. Foster relationships, partners, boarders, guardians, and other individuals are not considered family members in the creation of this variable.

Program derivation

The SPSS program statements for a sample survey year (1979-92) FAMILY SIZE variable are as follows:

COUNT FAMSZXX=RELR1 TO RELR15 (0 THRU 32,37 THRU 44,47 THRU 49)

IF (WEIGHTXX EQ 0) FAMSZXX=-5

After 1993, the roster was expanded to accommodate up to 20 individuals. The SPSS program is the same but the number of relationships to check is five larger. Additionally, the respondent is not on the household roster after 1992, so FAMSZXX is initialized to "1."

Household identification and linkages

The NLSY79 screening procedure allowed more than one member of a household to be selected for interviewing. The original 12,686 respondents were members of 8,770 households; 6,742 respondents or 53 percent of the sample were members of households from which more than one respondent originated, while 5,944 respondents or 47 percent were members of single respondent households (Table 2). To establish linkage of respondents originating from the same household, variables identify other interviewed household members and their relationships as of the 1979 interview. The 1979 variable providing the unique household identification number of each household is R00001.49, 'Household Identification Number' (HHID). The same HHID is assigned to all respondents who originated from the same household in 1979. In multiple-respondent households, the HHID corresponds to the lowest respondent 'Identification Code' of all respondents interviewed in that household; in single-respondent households, the HHID corresponds to the respondent 'Identification Code.' The HHID variable was constructed using other created variables from the NLSY79 main data set and exists only for 1979.  Multiple respondent households can also be identified through variables that identify other respondents in the same household and their relationship to the first respondent. Reference numbers include R00001.50-R00001.61, for example, 'Identification Code of 1^st Other Interviewed Youth in R's Household.'

Although these matches represent unique samples for a number of research topics, be aware that matches may be not be demographically representative due to the age restrictions applied to all members chosen from a household. The primary types of relationships that existed among respondents within multiple respondent households at the time the surveys began included brothers, sisters, husbands, and wives (Table 3). Other relationships included cousins, brothers- and sisters-in-law, step-brothers or -sisters, and other types of household members.

Household residence

Household residence refers to the type of dwelling or living situation of the respondent. Household residence information is available for the respondent at each survey point, for the respondent during his or her childhood, and for the respondent's children during recent surveys. The variable 'Type of Residence R is Living In' classifies the respondent's actual place of residence at the time of each survey. From 1979-86, it was created based upon responses to several questions asking about different types of dwelling units. In these years, several versions of the Household Interview Forms (the instrument completed before the main questionnaire and used to construct the household enumeration) existed. The universes for these different versions were dependent upon the type of dwelling unit in which the respondent lived (parental home, own dwelling unit, individual or group quarters), the sample type of the respondent (military or civilian), and who answered the household interview section questions (respondent or parent). The responses to questions designating type of residence from each of these versions were combined into one variable reflecting type of residence for the entire sample.

Beginning in 1987, the several versions of the Household Interview Forms were combined and all types of residences were coded in one question. Therefore, after 1986, this question is no longer considered a "created" variable. The 'Type of Residence R is Living In' variables include categories such as dorm, fraternity or sorority, hospital, jail or juvenile detention center, orphanage, religious institution, own dwelling unit, parents' household, and specific types of military quarters. The codes assigned to response categories for type of residence in 1979 differ significantly from those in other survey years. Also, in earlier years, respondents living in parental homes were treated as valid skips; in later years, these respondents were assigned a separate code that differs by year.

Retrospective information describing the respondent's childhood living arrangements was collected during 1988 in a three-part series of questions on the Childhood Residence Calendar. In Part 1, the respondent's identification of any type of parent with whom he or she lived for four or more months was recorded. Coding categories included biological, adoptive, or stepmother or father for each age from birth through 18 years, for example, 'Lived with Biological Mother at Birth,' 'Lived with Adoptive Father at Age 16.' Ages at which the respondent stopped living with a parent, the reason for ending shared living arrangements, and the frequency of visitation with the absent parent during the first year after coresidence ended were also collected. For those ages when the respondent reported not living with a parent, information was collected in part 2 of the Childhood Residence Calendar on:

• coresidence with grandparent(s), other relative(s), foster parent(s), or friend(s)
• residence in a children's home or orphanage, a group care home, a detention center/jail/prison, or another institution
• use of another type of arrangement
• for those ages ten and over, whether the respondent was left to be on his or her own

Variable titles for this series include 'Lived with Foster Parent(s) (Not Living With a Parent) at Age-7,' 'Lived in Children's Home/Orphanage (Not Living With a Parent) At Age-2,' 'Left to be on Own (Not Living With a Parent) at Age-15.' The number of foster or group care arrangements experienced by the individual is also recorded. Finally, in part 3 of this supplement for each age during which the respondent experienced more than one living arrangement when not living with a parent, the place at which s/he stayed the longest is identified. Data quality issues are discussed by Haurin (1991).

Information on the residence of respondents' children is available, for the most part, since the 1982 survey year. Note that edited variables based on the 1989 and 1991 raw data are not available until the subsequent year's release. These edited variables, cleaned and checked for consistency, include residences of each biological child in birth order (with some anomalies), such as 'Usual Residence of 7^th Child,' and combine information collected for residence of children of male respondents with that of children of female respondents. Coding categories include in the respondent's household, with other parent, with other relatives, in foster care, with adoptive parents, in a long-term care institution, away at school, deceased, lives part-time with both parents, lives part-time with the respondent and another person, and other. The unedited variables upon which the edited variables are based can be found in the "Fertility" section of the main youth questionnaire and include residence of all biological children; residence of all children born by the time of the previous interview, collected annually since 1984; and residence of all children born since the last interview, collected since 1983. Unedited residence information for nonbiological children is available for 1985, 1986, 1988, 1990, 1992, and from 1994 forward. Coding categories for all unedited variables are the same as for edited variables.

References

Haurin, R. Jean. "Childhood Residence Patterns: Evidence from the National Longitudinal Surveys of Work Experience of Youth." Columbus, OH: CHRR, The Ohio State University, 1991.

Morgan, William R. "Sibling Influences on the Career Plans of Male and Female Youth." Columbus, OH: CHRR, The Ohio State University, 1983.

Geographic data for NLSY79 respondents fall into two categories: information on the main public file and more detailed information released as restricted-use Geocode data. Table 1 lists NLSY79 geographic variables with their areas of interest and corresponding documentation found in the NLSY79 Geocode Codebook Supplement and the NLSY79 Codebook Supplement. Variables with a "Geocode" areas of interest are restricted-use data; all others are public use.

Geocode file variables

The Geocode files provide data on NLSY79 respondents' residence at the State, county, and metropolitan statistical area levels, merging information from Census reference files and data books, and includes additional variables such as local unemployment rates, job location, and college and military discharge locations where available.

• Information on the State, county, and metropolitan statistical area of residence for each respondent (the current residence variables) are merged with information from several other data files, namely the City Reference File (Census 1973, 1982, 1983, 1987, 1992) and the County & City Data Book (Census 1972, 1977, 1983, 1988, 1994), to provide detailed information on the environmental characteristics of the State, county, and metropolitan statistical areas in which each NLSY79 respondent resides. Note: Users may attach additional county and metropolitan statistical area-level data from a variety of sources by simply merging information from the desired source with the Geocode data based upon the State, county, and metropolitan statistical area of residence codes in the Geocode file.
• For select survey years, Geocode information is available on the location of respondents' jobs, the location of colleges attended, and the point of discharge from military service.
• Unemployment rate of each respondent's labor market of current residence:
  • The source of the 'Unemployment Rate' variables is the May issue of the Bureau of Labor Statistics' Employment and Earnings for the year following the survey year. Figures from March of each survey year are used. This table supplies unemployment rates for each State and for selected metropolitan statistical areas. Respondents who reside within one of these metropolitan statistical areas are assigned the appropriate unemployment rate. For those residing outside of these areas, a "balance of State" unemployment figure is computed using State total figures for the size of the civilian labor force and the number employed and subtracting the population living in metropolitan statistical areas.
  • Additional information on these variables can be found in Appendix 7 in the NLSY79 Geocode Codebook Supplement.

Types of county or Metropolitan Statistical Area environmental characteristics in the NLSY79 restricted-use Geocode data

• Population sizes
• Percent of population that is:
  • urban
  • black
  • female
  • under 5 years old
  • 65+ years old
• Birth/death/marriage/divorce rates
• Physician and hospital bed rates
• Crime rates
• Poverty level data
• Educational attainment levels 
• Median family and per capita income
• Recipients of and payments from:
  • AFDC
  • SSI
  • Social Security
• Labor force statistics:
  • total labor force
  • civilian labor force
  • number of females in the civilian labor force
  • civilians unemployed versus employed
  • percent employed in various industries
• Unemployment rate for labor market of residence

Geographic residence

Detailed geographic mobility information was collected during the 1979-80, 1982, and from 2000 forward; data were gathered on the country/county/State and timing of up to five residential moves since January 1978 or since the last interview. Beginning in 2000 only significant geographical moves were recorded.

Neighborhood quality

The neighborhood quality series (1992, and 1994-2000), is taken from the National Commission on Children Parent & Child Study, 1990 Parent Questionnaire. In this series of questions respondents rate how much of a neighborhood problem issues such as crime, lack of police protection, unsupervised children and joblessness are.

Other geographic variables

Users may obtain special permission to use zip code and Census tract data available at the BLS offices in Washington, DC.

Edited versus unedited versions of state/county of residence

For some years (1979-82, 1988-89, 1991-92), two versions of the State and county of residence variables have been included in the "Geocode" files. The set occurring at the beginning of each file is the edited version, while the variables found near the end of the files for these years are unedited. If the variable has an actual source question number/name, it is the original from NORC. If the source question name says created, it is the edited/created version. Note that the unedited variables are sometimes combined into a single variable, with the State and county code appended to each other. These raw variables are preceded by the word "GEOCODE" in the variable title. The edited residence variables contain the corrections made for erroneous address information and are the ones from which the Geocode files themselves are constructed. Users should be aware that the edited version of these variables does not contain data for those respondents who are in the active military forces or who are living abroad or in a U.S. territory.  Codes of "-4" appearing in the unedited versions of the State or county variables (because foreign country and U.S. territory codes are placed in one field or the other) should not appear in the edited versions of these residence variables.

Geocode procedures for assigning residence codes and hand-editing discrepant cases

During the 1988 hand-editing process, it became evident that the telephone numbers were very accurate, even in cases for which the address information contained discrepancies. Beginning in 1989, the area code and phone exchange were used to assign State and county of residence codes. The State assigned by the area code was then compared to the State assigned on the basis of zip code alone and the State contained in the original NORC respondent file. A "quality of match" variable was computed on the basis of how well these States match. For a more detailed discussion of these new assignment and matching procedures, refer to Appendix 10 in the Geocode Codebook Supplement. This process was used through the 1994 release.

The hand-editing procedure has also been streamlined. In 1989, the first year in which the phone assignment procedure was used, the residence codes assigned on the basis of the area code and exchange were compared to the raw residence variables received from NORC. Those with information that did not match were identified for individual examination. Ideally, the discrepancies requiring individual examination would be reduced to those cases which are "genuine movers" or which have zip codes covering multiple counties and would require some verification that the correct county was assigned based upon the phone information. The current process for identifying discrepancies and hand-editing is aimed more directly at achieving this objective. 

Beginning in 1990, the residence codes assigned based on phone information were compared to the 1989 CHRR-edited residence information to identify cases for individual examination. Because the previous year's edited variables incorporate the corrections that were made in the hand-editing process from earlier years, repeated editing of the same cases across years decreased. Through this process, the discrepancies in residential Geocode information were reduced. The number of cases requiring individual examination also decreased and was restricted more closely to the population of "genuine movers" and people with multiple-county zip codes and phone numbers that require verification of county of residence. 

The hand-editing process in previous years included not only these genuine movers and multi-county zip code dwellers, but also other cases for which elements of the address are simply in error or incompatible with each other. Some of these cases could potentially require editing for the same errors in more than one year, even if the respondent stayed in one location. Hand-editing procedures were further streamlined, and in some cases automated, to produce the 1992 data.

Beginning in 1996, a new procedure for verifying and assigning correct final Geocode information was instituted. This procedure is now performed using specialized address tracking Geocode software. The processes are described in Appendix 10. It is the belief of CHRR staff members not only that the current procedures are more efficient in identifying true discrepancies and streamlining the hand-editing process, but also that they result in more accurate and consistent assignment of State and county codes in general. 

Missing values, New England cases, and mobility

Missing values in location of residence variables and metropolitan statistical area codes are associated with respondents who are in the active military forces or who are living abroad or in a U.S. territory. Users should be aware that, because the New England County Metropolitan Area (NECMA) codes are not comparable to metropolitan statistical areas from the remainder of the country, New England cases are eliminated from some of the procedures used to construct the Geocode files.

The review and hand-editing process has been periodically revised to improve the accuracy of the data and the efficiency of data production. The potential implications for effects on mobility rates between some years due to these changes have been noted in Appendix 10. Users should read Appendix 10 carefully to gain a better understanding of the issues outlined above and their implications for specific research endeavors.

Variables available within the NLSY79 provide information on the sex of each respondent, their children, and members of their household. Information on the sex of the respondent can be found in:

• a single 1979 variable, 'Sex of R' (R02148)
• a set of yearly interviewer remarks variables, 'Int Remarks - Sex of R' 

The 1979 'Sex of R' variable (R02148.) is derived from R01736., 'Sample Identification Code,' a variable which defines each respondent's membership in one of the subsamples that compose the NLSY79 (such as the "cross-sectional male, nonblack/non-Hispanic poor," "supplemental female black," and so forth). Subsample identification was based on information gathered during the 1978 household screening.

Date of birth information was collected from each NLSY79 respondent during the 1979 and 1981 interviews:

• The variable 'Age of R,' gathered during the 1979-83 surveys, is the self-reported age of the respondent as of the interview date.
• The NLSY79 main data files also contain a yearly created variable, 'Age of R at Interview Date.' These created variables are constructed using the 1981 date of birth information coupled with the 1979 birth date for the 491 respondents not interviewed in 1981. 

Table 1 depicts age distribution of the NLSY79 for the 1979 survey year. Table 2 depicts age distribution of the NLSY79 for the most recent survey year.

Beginning with the 2006 survey year, questions about retirement preparation and expectations were introduced as respondents reached their fifties. Table 1 outlines the retirement preparation/expectation variables, along with the survey years in which they were included. These variables are available in the NLS Investigator by searching for the question name root RETIRE_EXP.

In 2018, the retirement section was revised and expanded to allow respondents, many of whom were beginning to retire, to provide more comprehensive details about their retirement funds. Information about types of retirement savings and income expectations can be found in the Pension Benefits & Pension Plans section and by searching the NLS Investigator using the RETIRE_FIN question name root.

Additionally, in the 2018-2022 survey years, respondents were asked if their employer had ever offered an early retirement window, one with a special financial incentive like a cash bonus or improved pension benefits. These variables are available in the NLS Investigator by searching for the question name QES-EARLYOUT.

Prior to 2010, only limited information was collected on business ownership in the NLSY79. In 2010 (round 24), NLSY79 respondents who were current or former business owners were asked a lengthy series of questions about each business owned since age 18. The business ownership questions were also asked in subsequent survey years for those not interviewed in 2010. 

Respondents who reported having owned a business gave the year each business was established and how ownership was acquired: whether the respondent established the business themselves or with partners, received ownership as a gift, purchased ownership, inherited ownership, or received an ownership stake through marriage. Respondents answered questions about working for a related type of business prior to starting their business, the source of the money used to establish or acquire the business, the number of employees and the number of physical locations of the business, the legal form of the business (sole proprietorship, corporation, etc.) the sales or revenue in a typical year, and whether the business was family owned.

In addition, all NLSY79 respondents interviewed in round 24 (regardless of "own business" status) were asked several questions on family ownership of businesses, their own patent-seeking activities, and whether they consider themselves to be entrepreneurs. These questions were repeated in subsequent rounds for those who missed the round 24 interview.