NLSY79

Class of worker data have been collected during each interview. These variables indicate whether a respondent:

• works for a private company or individual for wages, salary, or commission
• is a government employee
• is self-employed in his or her own business, professional practice, or farm
• is working without pay in a family business or farm

Respondents indicating that they are government employees are asked a follow-up question on whether they work at the Federal, State, or local level; self-employed respondents are asked whether their business is incorporated or unincorporated. These questions are similar to those asked in the Current Population Surveys.

 The NLSY79 collects detailed information about individual employers for whom a respondent has worked. These data are gathered within several sections of the main questionnaire and in job-specific instruments called Employer Supplements, which were administered in some years as separate instruments. Information includes:

1. the types of employers about whom information is collected during each survey round
2. the variable series which provides a cumulative count of employers for whom a respondent has worked

Employer Data Collection

Detailed information is collected during each interview on new and previously reported employers for whom a respondent has worked since the date of the last interview. The list of employers is built in the OnJobs module (see description below, and Appendix 9: Linking Employers from OnJobs Section to Employer Supplement and Through Survey Years, for more details and hypothetical examples) by identifying three sets of employers: 

1. Employers with whom the respondent was actively employed at the date of last interview (or "dli" employers)
2. Previously reported employers with whom the respondent was NOT actively employed at the date of last interview, but for whom the respondent has worked SINCE the last interview.
3. new employers for whom the respondent reported working since the date of the last interview

Before 1994, the current or most recent employer, called the "CPS employer," is differentiated in the data set from other employers for whom the respondent reported working since the last interview by title (that is, start date for CPS job, start date for Job #2, start date for Job #3, and so forth). Beginning in 1994, CPS job information is simply labeled as "job #1" because job specific information is all collected in the Employer Supplement. Every employer for whom a respondent worked since the last interview, including the CPS employer, is identified within the data set by a yearly job number, for example, Job #1, Job #5, with the number reflecting the order (most recent to least recent) the respondent reported working for each. The detailed job characteristic information at the end of this section is collected for each CPS job, regardless of whether it is a full- or part-time job. 

Because the NLSY79 employer data collection relies on the successive administration of several survey instruments that not only gather information on multiple employers but also connect that information to data provided during earlier interviews, a brief overview of the mechanics of employer-related module questionnaire modules follows.

Administration of the Survey Instruments Collecting Job Information: Two different sections of the NLSY79 questionnaire and until 1993 separate employer-specific survey instruments called the Employer Supplements (ES) collect employer-related information. Using these instruments, interviewers gather details about all employers for whom a respondent has worked since the date of last interview. An interviewing aid called the Information Sheet is also provided to each interviewer; this document lists the names of employers reported during previous surveys and is used by the interviewer during the current interview to update each respondent's work record with a previous employer, if work with an employer took place since the date of last interview. 

A quick overview of the instruments and questionnaire sections used to collect NLSY79 jobs data and the function each performs is provided in Table 1. The sequence in which employer-related questionnaire sections are administered has implications for the universe of respondents for whom job-related information is available. During all surveys to date, the "Military" section of the questionnaire has been administered prior to the two employer-related sections, the "CPS" and "On Jobs," and the Employer Supplements. After completing the "Military" section of the questionnaire, those respondents serving in the active forces were skipped past most or all of the CPS section to the "On Jobs" section in order to determine if they had been engaged in any civilian work since the last interview. Those not currently in the active forces have been routed directly to the CPS section, where detailed information on their current or most recent job and other labor market activities is collected.

The universe for the CPS variables, thus, is civilian respondents--those not serving in the active armed forces--who were working for pay either during the survey week or since the date of last interview. The universe for the "On Jobs" module includes all respondents, both civilian and military. Users should note that although the sequencing of the "Military," "CPS," and "On Jobs" sections was modified in the 1993 CAPI-administered interviews, no universe changes occurred.

During each interview, a separate Employer Supplement is completed for each employer for whom the respondent worked since the last interview. Questions in each Employer Supplement link information about these earlier jobs with the employer information collected in the CPS section of the main questionnaire, if appropriate, and with the employer (job) number of this employer, if any, assigned at the previous interview. Users should note that, after the implementation of CAPI, the Employer Supplement physically became a part of the questionnaire. 

Capturing information on jobs outside of the traditional forms of employment: In rounds previous to 2002, it the language in the existing questionnaires presented challenges in capturing information about jobs outside of the traditional forms of employment. One key type of job is self-employment; respondents who own their own businesses sometimes had difficulty with questions phrased under the assumption that the respondent worked for someone else. The second type of job is nontraditional employment, wherein the respondent works for a temporary agency, under some type of contract, or in an on-call arrangement. Respondents in this kind of employment situation tend to have a large number of jobs and gaps in employment, and the survey had trouble capturing this information efficiently in past rounds.

On Jobs: Beginning with the 2002 survey, the On Jobs module serves two functions. First, as in previous survey rounds, the respondent reports all of his or her employers since the last interview, so that they can be included on the roster. Second, a new set of questions is asked about each employer, to ascertain whether the job has characteristics of self-employment, regular employment, or nontraditional employment.

On the basis of answers to the job classification or job type questions, the respondent is classified as self-employed if he or she owned at least 50 percent of the business, was the chief executive officer or principal managing partner of the business, or was supposed to file a form SE for Federal income taxes. Respondents also are classified as self-employed if they identify themselves as independent contractors, independent consultants, or freelancers. A job is classified as nontraditional employment if the respondent is paid by a temporary help agency, is an on-call worker (that is, is called to work only when needed, not in addition to regular hours), or works for a company that provides services to other companies under contract. To confirm that the respondent is a regular employee, a final set of questions asks whether the respondent's supervisor is employed by the same company and whether the company provides the respondent's tools or equipment. If the job is still unidentified at this point, the respondent is simply asked to describe his or her unique situation and answer questions in the regular Employer Supplement to the survey. Experience with 2002 and 2004 survey rounds indicates that this situation is extremely rare.

2002 was the first survey years in which job type questions were included in the questionnaire. Many jobs reported in previous survey rounds were classified by survey staff in advance of the 2002 fielding. For example, if, in the previous round, a respondent had reported working at a job with regular hours, a supervisor, and so on, staff assumed that the job was regular or traditional employment. Staff used the vast array of data available to make such preclassifications. The job type questions in the On Jobs module were not asked of most respondents who had been preclassified in traditional jobs. A random subset of these respondents was routed through the questions to verify that the preclassification criteria were accurate, while the majority of respondents were asked to verify that the preclassification fit the employment situation.  In addition, all self-employed and nontraditional jobs also were verified during the interview. In 2004 and after, the full set of job classification questions was asked only about new jobs. For employers continuing from the previous interview, respondents are asked to verify the job classification or update it as necessary (for example, if the respondent ceased being a regular employee and entered into a contractual arrangement).

Employer Supplements: After a roster of jobs  the respondent has worked in since the last interview has been compiled, along with job classifications for each, the survey moves into the Employer Supplements, which contains questions relevant to three types of employment situations: 

1. Regular or traditional job: The only significant change in the regular employment questions relates to teachers. Because teachers often are paid for only a set number of months per year, they sometimes found it difficult to answer the pay rate questions. To address this issue, a new set of pay rate questions was added in 2002 for all jobs identified as teaching positions, including both K-12 schools and colleges. Teachers are asked whether they are paid by the course or are salaried. If they are paid by the course, the survey records the amount paid per course and the number of courses taught in the calendar year. If, instead, the respondent receives a regular salary, they are asked about the number of paychecks received per year and the amount received per check. The survey also records payments for additional assignments, such as a coaching stipend or summer school pay. This approach allows survey staff to create an accurate rate of pay, regardless of whether the teacher is paid by the course or is on a 9-month, 10-month, or full-year schedule.
2. Self-employment: Although some questions are the same as in the traditional Employer Supplement, many questions were reworded to make them more applicable to self-employment.  New questions, tailored to record critical information about the respondent's business, were also added. The respondent reports whether the business is a farm or ranch, whether the business is based in the respondent's home, whether there are other partners in the business, and how many paid employees the business has. Respondents also state whether they consider the business to be their main or secondary job. As with questions about traditional employment, respondents report periods not working, hours usually worked per week, industry and occupation, whether the business is incorporated, the availability of employee benefits, the availability of and participation in a pension plan, and job satisfaction. A new series of questions was added in 2010 asking for more extensive details about business ownership beyond the basic information previously collection in the section on assets.  For more details, go to the Business Ownership section of this guide.
3. Nontraditional employers: This area encompasses the most substantial changes from previous surveys. Respondents working in nontraditional situations tend to have sporadic employment with frequent job changes. Prior to 2002, reporting of this type of employment caused some confusion. For example, some respondents who were employed through a temporary agency reported each separate job they were assigned to through that agency and each gap between those temporary assignments. This led to lengthy and difficult interviews. The new On Jobs and Employer Supplement sections more clearly specify that the respondent should consider the temporary or contracting agency as his or her employer, rather than reporting each assignment separately. The new sections also guide respondents in reporting these types of jobs correctly. 

Some questions in the series on nontraditional employers focus on the temporary or contracting agency. Information recorded about the agency (rather than each assignment) includes hours usually worked, the availability of employee benefits, the availability of and participation in a pension plan, union status, and job satisfaction.

Respondents then report on their assignment history, including the number of assignments since the last interview or the start of the the association with the agency, the amount earned, whether they are currently on an assignment, and, if so, how long that assignment is expected to last. If the respondent reports five or more periods not working during his or her tenure with the temporary agency, a series of questions is asked about the number of weeks without an assignment and whether any of those weeks were spent working for another employer. For both the longest spell not working and the most recent spell, respondents then report the dates of the spell, the reason why they were not working, whether they were looking for work or were on layoff, and, if they were not looking for work, the reason why they were not looking. Respondents with fewer than five gaps in tenure with an employer report this information for each spell.

Finally, respondents answer a set of questions about their most recent assignment through the temporary or contracting agency. These questions generally mirror the questions asked about traditional employers. With reference to the most recent assignment, respondents report the industry and occupation of the job, job sector, whether the business was incorporated, the rate of pay, and the shift worked.

Pay close attention to question paths followed for each job. Although the set of Employer Supplement questions for each type of job is described separately in the previous paragraphs, the actual survey instrument does not contain three separate and discrete sets of questions. In many cases, the same question is asked regardless of the type of job. For example, respondents report on the availability of employee benefits for all three types of job. The questions on benefits appear only once in the survey instrument, but will appear in the question path for all three types of employment.

NLSY79 Employer Types

This section discusses the various types of employers about which information is collected during each survey. Incorporated within the discussion is specific information on:

1. How the CPS employer is designated
2. How information on the CPS job--collected during many survey years within two separate survey instruments--can be linked
3. How a specific employer for whom a respondent has worked since the last interview can be matched to the same employer reported during a previous interview

Current or Most Recent (CPS) Employer: The NLSY79 replicates questions from the Current Population Survey, which specify the employer(s) with whom a respondent is associated at the time of the survey. A "CPS employer," or current/most recent employer, is designated for each civilian NLSY79 respondent who reported working for pay at some point since the last interview.

The methods employed to identify an employer as the CPS employer vary by interview mode. During the 1979-92 paper-and-pencil interviews, the CPS job was identified by NORC interviewers from the respondent's answer to the following open-ended question:

"For whom did you work last (week)?  IF MORE THAN ONE EMPLOYER, PROBE:  for whom did you work the most hours during the last week (you worked)?"

The actual name of the respondent's employer [for example, the Aspen Ski Company, Oliver's Saloon] is manually recorded in the questionnaire and entered on the cover page of an Employer Supplement. Because not all respondents were at work during the survey week and some were at work for more than one employer, detailed instructions on how to identify the CPS employer are provided to NORC interviewers within the round-specific Question by Question Specifications manuals. A summary of instructions from the 1996 interviewers' manual appears in Table 2.

Information on the CPS job has been collected during the 1980-93 survey years within the CPS section of the main questionnaire and within a single Employer Supplement for 1980-1998. Comparable information was gathered during 1979 in the "CPS" and "On Jobs" sections of the main questionnaire. A variable named, 'Is There a CPS Employer?' R41819. in 1993 for example, specifies whether there is a CPS employer for each respondent. The various types of job characteristic information collected about each CPS job/employer are discussed below. 

Beginning with the 1993 CAPI-administered interviews, the CPS job is identified by internal CAPI procedures which factor in, for civilian respondents, stop date information specific to each recorded job. Additional information on CAPI CPS-designation procedures, such as how the CAPI program handles multiple employers with the same stop date, can be found in Appendix 13: Intro to CAPI Questionnaires and Codebooks. 

Employers since the Last Interview--Jobs #1-#5: The "On Jobs" section of the questionnaire and the job-specific Employer Supplements, both administered during most survey years immediately after the CPS section, gather information about each employer for whom a respondent worked since the date of last interview.  A separate Employer Supplement (ES) is completed for each since-last-interview employer. Although information is collected about all employers for whom a respondent worked since the last interview, data on only the first five jobs or employers are released on the NLSY79 main data set. In each survey, the number of respondents who report more than five jobs is less than one percent of those interviewed.

In 1979, the CPS job is always Job #1. In 1980-1992, interviewers were instructed to collect information on the jobs a respondent held in reverse chronological order, with the current or most recent job first, followed by the next most recent, and so forth. This means that for most--although not all--respondents, Job #1 will be the CPS job, Job #2 could be the job held concurrently with the CPS job or immediately preceding it, and so forth. The job number to which the content of the variable refers e.g. is appended to each variable title. The mechanics used to designate the CPS job in CAPI interviews starting in 1993 results in all CPS jobs being Job #1. Before 1994, the collection of information on the CPS job within the CPS section of the main questionnaire and within a separate Employer Supplement means that researchers may find it necessary to link information collected within the two instruments or sections. The variable series that enables these data to be linked is described briefly below.  Users should note that while the data set contains only information on the first five jobs, all created variables, such as time worked during the year, are based on information on all jobs reported by the respondent.

Linking Job #1 - Job #5 to the CPS Job: During administration of each Employer Supplement, an interviewer check item determines whether the employer about whom information is being collected, for example, Job #1, is the CPS employer recorded in the CPS section of the main questionnaire. Interviewer responses to this item are found in the variable series 'Int Check - Is Job #X Same as Current Job?' Available for each survey year, these variables can be used to link information about the CPS job collected in an ES to that collected about the CPS job in the main questionnaire for survey years 1980-92.

Employers at or Prior to Date of Last Interview: In order to construct a continuous work record with each employer, information collected during the current interview is connected to data gathered about the same employer during earlier interviews. Information is updated on two sets of employers: (1) those employers for whom a respondent was actually working at the time of the last interview; and (2) those employers for whom a respondent had previously worked but for whom he or she was not working at the last interview date. Note: Information on these previous-to-last-interview employers is collected only if the respondent reports working again for that employer.

A separate interviewing aid called the Information Sheet provides NORC interviewers with a listing of the names and respective job numbers of each of these previous employers. Each set of employers is listed under a different Information Sheet item, for example, Item 05, Item 06, and so forth. Users should note that these Information Sheet item numbers are not consistently numbered across years, for example, the "at date of last interview" employers appear as Item 12 in 1980 but as Item 05 in 1991, while the "previous to date of last interview" employers appear as Item 13 in 1980 but as Item 06 in 1991. These Information Sheet item numbers are referenced within the Employer Supplement question verbatim responses and will be found in the title of each such variable, as illustrated below. Questions at the beginning of each Employer Supplement route the interviewer to the name and job number of each such employer listed on the Information Sheet in order to connect information collected during the current survey with information on that same employer gathered during an earlier interview. Employers can be linked across rounds using the PREV_EMP# variables. See Appendix 9 for more information.

Jobs Ever Reported as of Interview Date: The variable series 'Number of Jobs Ever Reported,' created for each survey year, provides a cumulative measure of the number of different employers that a respondent has reported up to the point of interview. Any employer identified as different from employers at the date of last interview and in the period before the date of last interview is counted as a different or new employer. This set of variables is created by simply counting each such employer in a current survey year and adding that sum to the total from the previous interview year in order to provide a cumulative figure through all survey years. 

Users should be aware that a small degree of double-counting of employers may exist in these variables. It is only possible to track a given employer between contiguous interview years in which information was collected on the specific employer. It is therefore conceivable that a respondent who works for a particular employer during one year, leaves that employer for the next year or more and then subsequently returns to that same employer would appear to be working for a new employer during the second tenure because the previous tenure with that employer would have slipped out of scope for tracking purposes.

Types of Job/Employer Characteristics Information

Descriptive information is collected about each job or employer and about the position a respondent occupies with that employer. The level of detail available for a given job varies by (1) whether that job was designated as the current or most recent job and (2) the number of hours per week or number of weeks worked. Complete job characteristic information is available for those jobs specified as the CPS job, as well as for those jobs at which a respondent reported working more than ten hours a week and for more than nine weeks since the date of last interview. This section briefly summarizes the differences in the kinds of data collected for the CPS versus non-CPS jobs. It then reviews the various types of job characteristic information which are available and refers users to other sections of the guide which discuss each characteristic more fully.

Be careful to distinguish these sets of job characteristic variables from the separate and distinct 1979 and 1982 data collections, which provide information on qualitative aspects of a respondent's current job such as degree of autonomy, variety, opportunity to deal with people, and job significance. This series can be distinguished from the variables discussed below by the phrase JOB CHARACTERISTICS ITEMS, which has been appended to each of the 22 1979 and 1982 variable titles. (See the Job Characteristics Index section.)

• CPS Job: All of the job characteristic information described below--including that on firm size and job satisfaction--is available for the job designated as the "CPS job." These data are available for any CPS job regardless of whether the job is a full-time, part-time, or temporary job. During the 1979-1993 interviews, all job characteristic information about the CPS job except that pertaining to usual earnings was collected within the CPS section of the main questionnaire. Beginning with the 1994 CAPI interviews, all CPS job-related information is gathered in the Employer Supplement. Wage information across survey years continues to be collected within the job-specific Employer Supplements.
• Non-CPS Jobs: Some detailed characteristic information is only available for non-CPS jobs meeting certain time and tenure requirements. Detailed questions are asked about jobs at which the respondent has worked for at least nine weeks since the last interview and at which the respondent generally worked at least 20 (through 1986) or 10 (since 1987) hours per week.

Brief summaries of select sets of job characteristic data appear below. References are provided to other sections of this guide that discuss these variables in more detail. Several other sets of job characteristic variables, such as union membership, coverage by a collective bargaining agreement, and whether a respondent's association with a given employer was the result of a Federally sponsored employment and training program, are also covered in other sections of this guide (such as Training).

• Class of Worker: For each CPS job (whether full- or part-time) and to each non-CPS job for which a respondent worked for more than ten/twenty hours a week and more than nine weeks since the last interview, a code is assigned indicating whether the respondent:

  1. works for a private company or for an individual for wages, salary, or commission
  2. is a government employee
  3. is self-employed in his or her own business, professional practice, or farm
  4. is working without pay in a family business or farm

  Both the CPS and non-CPS series further identify government workers as Federal, State, or Local-level employees and distinguish the businesses of self-employed respondents as incorporated or unincorporated. [See the Class of Worker section and refer to the "User Notes" in that section detailing the changes in coding for "Class of Worker" variables.]

• Firm Size: The number of employees both at the place where the respondent is currently employed and at other locations is available for the CPS job.  These data were collected during all survey years except 1981-85. Beginning in 1994, these variables are available for all employers.
• Fringe Benefits: During the 1979-93 interviews, information on the availability of various types of benefits provided by the CPS employer was collected for those respondents working 20 hours or more a week. Beginning with the 1993 survey, those respondents working 20 hours a week or less were also asked if their employer made any benefits available, and if so, which ones. Beginning in 1994, benefit information was collected for both the CPS and non-CPS jobs [See the Fringe Benefits section].
• Hours: Information on the number of hours worked at the CPS job, at each non-CPS job, and at all jobs combined is available for each survey year. A set of created summary variables provides a count of the total number of hours worked since the date of the last interview and during the past calendar year. Details on the type of shift and the actual clock hours worked have been collected during select survey years for the CPS job. Beginning in 1994, these data were collected for all employers (CPS and non-CPS).  [See the Time & Tenure with Employers and Labor Force Status sections.]
• Industry: A code from the Census industrial classification system is assigned to each CPS job (whether full- or part-time). A Census industry classification code is assigned to each non-CPS employer for whom a respondent worked for more than ten/twenty hours a week and more than nine weeks since the last interview. [See the Industries section.]
• Job Satisfaction: Respondents employed since the last interview are asked to rate, on a four point scale, how they feel about their current or most recent (CPS) job. Beginning in 1994, this information was collected for all CPS and non-CPS jobs. [See the Job Satisfaction section.]
• Occupation: A code from the Census occupational classification system is assigned to each CPS job (whether full- or part-time). A Census occupational code was assigned to each non-CPS employer for whom a respondent worked for more than ten/twenty hours a week and more than nine weeks since the last interview.  [See the Occupations section.]
• Wages: Rate of pay information, including the time unit of pay, is collected for each CPS and non-CPS job (whether full- or part-time but subject to minimum hours and weeks restrictions before 1988). A series of hourly rate of pay variables are created for each employer for whom a respondent worked since the date of last interview. [See the Wages section of this guide.]
• Job Tasks: In the 2016 survey year, a series of questions was added about job tasks encountered during the workday (CPS job only). Respondents were first asked how much of their workday involved 1) short, repetitive tasks; 2) physical tasks; and 3) managing or supervising others. In addition, they answered a question about the length of the longest document they typically read as part of their job. Respondents also estimated how often their job included problem solving, using advanced math, and personal contact with customers, suppliers, patients, students, and others.
• Job Stress: In the 2018 survey year, respondents answered a series of questions about job stress. First, they were asked if they had serious on-going stress at their job, such as extreme work demands, major changes, uncertainties, or not getting along with colleagues or boss. They then estimated the positive or negative effects their job had on their mental/emotional and physical health. They also were asked if it was possible for them to change the number of hours worked, have more flexibility with their hours, or move to a less stressful job position. In addition, they indicated whether their employer provided any special help should an employee's health limit his/her ability to work.
• Effects of COVID-19 on Jobs: In the 2020 survey year, respondents were asked about the ways their jobs had been affected by the COVID-19 outbreak, including questions about their work hours and earnings increasing or decreasing and if they were required to work remotely. To find COVID-related questions, use "CORONAVIRUS" as a the word-in-title search in NLS Investigator.

Some variation exists across survey rounds in the level of job characteristic detail available. "Job" should not be interpreted as occupation or employment duties but rather as an employer. If a respondent changes work activities for a single employer, this is counted as only one "job."

Comparison to Other NLS Cohorts: In each survey, extensive information on jobs and employers has been collected from NLSY79 young adults. Beginning in 2000, this series was greatly streamlined with the greatest detail asked only of the current or most recent primary employer. For employee jobs, respondents in the other cohorts have reported the following information in at least some survey years: start and stop dates, labor force characteristics, class of worker, collective bargaining status, and firm size. The Young Men have provided similar information about military service, including pay and occupational data; Older Men reported the dates of any military service. With the exception of the NLSY97, no information on freelance jobs has been collected from the other NLS cohorts, although job information for self-employed respondents has been gathered as a part of the regular employment section. For more precise details about the content of each survey, consult the appropriate cohort's User's Guide using the tabs above for more information.

Each survey collects the following employment information:

• a full work history of employment, including characteristics of the current or most recent employer and of any other employers for whom the respondent worked since the date of the last interview
• military service since the date of the last interview
• any gaps in employment since the date of the last interview

From this information and other retrospective information, a longitudinal record spanning from the date of, and to some extent the time preceding, the first interview through the most current interview date can be constructed for each respondent. The longitudinal record is maintained even for respondents who are not interviewed in interim years. Each year's questionnaire incorporates retrospective questions designed to recover as completely as possible information lost (or incorrectly reported or recorded) during previous survey years. 

For example, a respondent interviewed in 1984 and not interviewed again until 1989 will have a complete labor force history as of the 1989 interview, as information for the intervening period will be recovered in 1989. Researchers should be alert to the possibility of gaps and discrepancies in some records over time due to inconsistencies in respondent reporting or interviewer error. These inconsistencies have not appeared to be a major factor in the quality and completeness of the NLSY79 employment and labor force history.

The ability to link identical employers through survey years allows longitudinal examination of not only general labor force activity, but also employer-specific experience. Appendix 9: Linking Jobs Through Survey Years and Appendix 18: Work History Data both found in the NLSY79 Codebook Supplement, provide additional information. The Employer History Roster data, recently made available, provides other employer-specific characteristics.

Longitudinal work experience record

This section discusses information on various aspects of the longitudinal work experience record available for each respondent of the NLSY79.

Number of employers

The most basic longitudinal information available for respondents is the total number of employers for whom a respondent worked during a given period and the total number of employers (part-time and full-time) ever reported by a respondent. It is possible to construct fairly complete inventory of the number of jobs for all respondents from the age of 18 years and older; note the age effects discussion below.

"Employers" versus "jobs"

Unless explicitly noted, the NLSY79 work event history data are employer-based. Therefore, any reference to "job" is a reference to a specific employer. Information about specific duties and positions or changes in duties or position is collected, with reference to a specific employer, only at the point of interview (with limited exceptions in specific survey years). For example, a respondent may regard himself/herself as having held a number of "jobs" or positions with employer #1 (Job #1). However, any information collected about these different positions would be included as information about the respondent's experience with that employer (#1) at the point of interview for a specific year. Based upon this characteristic of these data, researchers are cautioned that counting changes in occupations can not necessarily be equated with total job changes or employer changes. For example, it is possible for a respondent to hold more than one occupation with the same employer during the time between interviews. Yet, except in restricted survey years, the only occupation specifically reported at the point of interview would be the current/most recent occupation. Likewise, a respondent may hold the same occupation through his or her tenure with several employers.

Effect of age of respondent on employment information

For those respondents who were 18 or older at the time of the first interview (1979), information about work history is recovered retrospectively to the age of 18. Information preceding this age may be relatively limited for these respondents. However, reported employers became part of the ongoing survey record of respondents who were younger than 18 at the time of the first survey. The depth of information for all jobs but the CPS job for respondents younger than 16 is somewhat restricted during the early survey years. Despite restrictions, a good deal of information is still available for those who were 15 years of age or under at the first interview point. More information on age restrictions is available in Employment: An Introduction (see Table 1 in that section).

Part-time versus full-time employers

If respondents report part-time or short-term employers who are not the CPS employers, there are restrictions on what information was gathered about industry, occupation, wages and class of worker. For a table of the universe restrictions, go to the section on Industries. This is also the case for year-specific modules, such as the 1990 promotion series. However, other basic information for part-time employers is available, such as start and stop dates, gaps within tenure with part-time or temporary employers, and hours worked per day and per week. In the event that a part-time/short-term employer is the CPS employer, complete data, including industry, occupation, and class of worker, are collected regardless of the nature of the job. Therefore, reasonable opportunity exists for comparisons of part-time/short-term and full-time employers, particularly if the part-time/short-term employer is the CPS employer.

Double-counting of employers

Users should be aware that a small degree of double-counting of employers may occur when data are collected. Until 1998 employers were only tracked between contiguous interview years in which information was collected on the specific employer. It is therefore conceivable that a respondent who works for a particular employer during one year, leaves that employer, and then returns to that same employer after a year or more, would appear to be working for a new employer during the second tenure because the previous tenure with that employer would have slipped out of scope for tracking purposes (see also the Jobs & Employers section). Starting in 1998, the NLSY79 began keeping a roster of all employers to enable the CAPI instrument to recognize when a respondent returns to an employer that they left a number of years earlier.

Despite some limitations, NLSY79 data allow for the construction of a relatively complete and detailed employment history for respondents from January 1, 1978 (and possibly points preceding), through the most current year in which a respondent was interviewed.

Tenure with specific employer

A second type of basic information that can be constructed from NLSY79 longitudinal labor force experience data is a history of tenure (in weeks) with each employer reported up to the most current survey year for a given respondent. Tenure excludes any unpaid within-job gaps. (see the Time & Tenure with Employer section for additional information).

A total tenure through contiguous survey years is available for all employers, full- and part-time, for whom valid start and stop dates of employment are reported. This is accomplished by linking identical employers through contiguous survey years; see Appendix 9 in the NLSY79 Codebook Supplement for more information. The construction of employer tenure occurs within the more expansive programming structure that produces the separate NLSY79 Work History data items. For more information on the consequences of missing start and stop dates, users should refer to the Work History section, which is devoted to a discussion of these data.

"Employer" tenure versus "job" tenure

Researchers must be cognizant of the employer-based nature of these data (see the discussion above on "Number of Employers"). Tenure figures reflect time with a specific employer, not time performing a specific occupation with an employer. However, by using data on reported timing and nature of promotions present in two survey years for the CPS job and in 1990 for all jobs, it may be possible to impose some sense of change in occupations over certain periods of time.

Double-counting of employers and "broken" tenure

The limited possibility of double-counting of employers (discussed above) allows a slight chance of tenure with a single employer being calculated as tenure with two separate employers. An employer for whom the elapsed time between stints exceeds the capacity for continuous tracking will likely appear as two separate employers with two separate (and shorter) total tenure periods.

Gaps within tenure with specific employer

Total tenure with an employer extends from reported start date to stop date. In addition, respondents may report gaps of a week or more during the period of association with an employer that fall within the period between start and stop dates. Unpaid gaps within tenure with the same employer are reported in association with a specific employer. They occur between the start and stop dates given for an employer. The respondent may not consider himself/herself completely disassociated from the relevant employer during these periods, although he or she was not actively working for that employer. Specific variables for each gap include start and stop dates; the reason that the respondent was not working during a given gap; the number of weeks that a respondent was unemployed (looking for work or on layoff) or out of the labor force (OLF or not looking for work) during a given gap; and, for those who were OLF at some time during a gap, the reason they were not looking for work.

Although a respondent may report himself or herself to be out of the labor force or unemployed during these gaps, these weeks are included in the calculation of total tenure with that employer because they occur before the respondent has reported an actual stop date for his or her association with that employer. Therefore, these weeks are considered part of the period for which the respondent considers himself/herself associated with that employer.

Users wishing to adjust total tenure with an employer to reflect such gaps must do so by calculating the length of reported gaps and eliminating them from the total tenure value. This can be done over the total of reported gaps or selectively, depending upon the reason or labor force activity classification (out of the labor force versus unemployed) of individual gaps.

Cumulative labor force experience

For survey years 1979-1998 and 2006, the standard set of definitions of labor force status used by the Current Population Surveys (CPS) was used for coding the employment status of NLSY79 respondents "Labor Force Status." The NLSY79 Work History programs incorporate further refinements to allow for weeks of indeterminate status, due to erroneous respondent reporting or interviewer recording (see the Work History section). The NLSY79 summary indicators are then constructed, using these Work History definitions for weekly labor force status. The Labor Force Status section of this guide includes detailed definitions of CPS and NLSY79 Work History labor force concepts.

The detailed collection of dates of employment and gaps in employment over the history of the NLSY79 allows construction of a cumulative picture of a respondent's labor force activity over the course of the survey. A large number of summary variables are created based upon the week-by-week labor force status arrays produced by the Work History program (see the Work History and Labor Force Status sections for more information). These summary variables provide a count of the number of weeks a respondent held a given labor force status, the total number of hours worked (if any), and the total number of weeks since the respondent's last interview. Variables are also calculated indicating the percentage, if any, of weeks that are not accounted for in the summary variables discussed above, due to missing data or indeterminate status in the Work History arrays.

These variables, constructed within the Work History programs, consist of two sets. One series uses "Last Interview Date" as the reference period, and the second uses "Past Calendar Year" (the full calendar year previous to the year of current interview) for its summations. However, it is possible to construct similar cumulative figures for periods of time of particular interest to them. For instance, one may be interested in compiling a summary of work or labor force experience for respondents over a specific five-year period. Similarly, a summary of activities with employers having certain characteristics (part-time, temporary, full-time, CPS, certain levels of earnings, and so forth), as well as the extent of such practices such as dual job holding among respondents, may be compiled. A gaps history can also be assembled using, as appropriate, gaps reported within the tenure with an employer or gaps where no employer affiliation is reported.

Cumulative active military service

Cumulative weeks of active military service are constructed during the creation of the NLSY79 Work History data set. However, civilian employment has precedence over military activity in the week-by-week labor force status arrays. Therefore, the number of weeks in active military service in the past calendar year will not include any weeks during which the respondent also held a civilian job. The full period of active military enlistment can be verified by using data on enlistment and discharge dates from the actual military section in the main questionnaire. The number of weeks in the active military since the last interview is calculated by subtracting the starting week from the ending week so that the entire tenure is included.

Gaps between employers (no affiliation with an employer)

As mentioned, gaps may be reported between the start and stop dates for a given employer, reflecting periods for which a respondent considers himself or herself affiliated with an employer but not actively working. In addition, gaps in employment reflect periods when the respondent reported no affiliation with any employer. These gaps are often referred to as "between-job gaps."

Indeterminate labor force status during gaps

The exact duration of gaps in weeks (within-job gaps or between-job gaps) is available, as well as the number of those weeks the respondent was "out of the labor force (OLF) - not looking for work" as opposed to "unemployed - looking for work or on layoff." Therefore, if a respondent was unemployed for the entire period of the gap, the specific weeks for those labor force statuses can be determined. However, for a gap in which the respondent was OLF part of the time and unemployed part of the time, the specific weeks that the respondent occupied each status cannot be determined. Researchers should be aware that, while the number of weeks the respondent occupied each status is accurate, the precise weeks for each status may not be. The Work History Data section provides details on the assignment of non-employed labor force status.

Weeks with indeterminate activity

Users should be aware that, under some circumstances, it is not possible to determine labor force status for a given week. These indeterminations arise with incomplete or invalid start or stop dates for employers or gaps. For example, an element of the date is missing or the stop date precedes the start date. Variables reflecting the percentage of weeks that were unaccounted for since the last interview and in the past calendar year are computed. Hence, users may find respondents who worked 52 weeks of the year but also have 100 percent of their weeks unaccounted for. These variables alert researchers to problem cases that may need to be examined more closely or eliminated from analysis. The Work History Data section provides additional information.

Employer characteristic histories

It is possible to build a limited history of certain employer-based characteristics (earnings/hourly wages, occupation, and so forth). These histories will be limited in the sense that many of these characteristics are reported only at the date of each interview.  Should change occur from one interview date to another, the point of actual change cannot, in most instances, be precisely determined. (Information collected in select survey years may permit more definitive identification of interim changes occurring between interview dates for certain characteristics.)

Strictly speaking, it is possible that an occupational change from one interview year to the next could reflect only one of several during the period between interviews. Characteristics such as hourly wage may be of less concern in this regard, as some numeric progression or regression should be apparent. Even for these indicators, interim and temporary cutbacks in compensation in times of economic downturn may be missed. Noting these limitations, it is possible to construct a reasonably complete history of experience with specific employers, such as CPS employer or all employers.

CPS employer as a primary focus

The CPS employer (current/or most recent at date of interview) is the focus of many researchers. These employers can be linked in much the same way as non-CPS employers, with one extra set of variables identifying the employer as CPS. However, it is important to note that, while the CPS employer is usually the first employer, this is not always the case in survey years 1980-92.

Discrepancies in the order in which interviewers administered, or respondents reported, employers for Employer Supplements resulted in a relatively small number of cases in each pre-CAPI survey year for which the CPS is not the first employer, but rather Job #2 or Job #3, etc. The CPS employer can be identified in each year by a "yes or no" variable, which is present for each employer. A "1 - yes" code indicates the CPS employer. It is possible that an employer that is the CPS employer in one year and remains the CPS employer in the next year will be Job #1 in the first year and Job #2 (or higher) in the second year. In this case, the information for Job #2 in the second year would be a continuation of the information for Job #1 in the first survey year. While in 1979 Job #1 is always the CPS job, in 1993 and after, the CAPI instruments ensure that the CPS job (if one exists) will always be Job #1.

Information has been collected during all survey years on the type of organization providing the training in which NLSY79 respondents participated. In addition to regularly fielded general training questions, special data collections focused on:

• government training administered in the early years of the NLSY79
• high school courses
• degrees and certifications
• and time use provide supplementary information on NLSY79 respondents' training investments

In general, the "Training" or "Other Training" sections of each NLSY79 questionnaire:

1. collect information on each respondent's participation since the date of the last interview in three (or more) training programs
2. confirm and update information on two (or more) training programs in which he or she was enrolled on the date of last interview

Provider types for which data have been consistently gathered across survey years include company training, business school, vocational/technical institute, and apprenticeship program. Questions fielded during select survey years specified other training providers such as nurses program, barber/beauty school, flight school, seminars or training programs at work/outside of work, and vocational rehabilitation center. The names of identical and additional agencies can be found in the:

• 1979-87 government training and jobs programs questions
• 1979 degrees and certifications data collection
• 1980 time use in "other training" series

Data on government training was collected from 1979 through the mid-1980s for NLSY79 respondents. The primary concern of NLSY79 questions was whether jobs held by the respondent had been obtained through a program funded by the government. The survey also explored whether training and supportive services had been provided. In general, information was gathered on:

• enrollment patterns
• program sponsorship
• types of training
• supportive services
• job placement services provided

Related Variables: The Educational Attainment & School Enrollment and School & Transcript Surveys sections of this guide review some additional and related variables.

Core Data Collection

For each program, a core set of variables is collected on the type of provider offering the training, start and stop dates (month and year), whether the training was completed, and the number of hours per week usually spent in each training program. Variables include:

• 'Any Vocational/Technical Training Enrolled'¹
• 'Attended Vocational/Technical Program or On-the-Job Training'
• 'Type of School or Vocational/Technical Program Enrolled In'
• 'Month/Year Began'
• 'Month/Year Completed/Left'
• 'Completed Vocational/Technical Program Enrolled In'
• 'Hours Per Week Spent at Vocational/Technical Program Taken'

¹ Note that the 1979-86 data collections asked only about training programs in which the respondent had been enrolled for more than one month.

Year-by-Year Variations. During the 1979-86 surveys, the focus of the NLSY79 training data collection was on the types of formal training programs in which a respondent was enrolled other than those already reported in the previously administered jobs, government training, military, and regular schooling sections of the questionnaire. After 1987, the series of questions concerning government-sponsored training was no longer fielded and the "Other Training" section was renamed "Training." The types of information collected for all years of the survey differ and are discussed below (Table 1.)

Table 1. Year-by-Year Variations in Training Data Collection

Table 2. Definitions of Training and Training Providers: Definitions from the NLSY79 Question-by-Question Specifications. (1991)

Types of Skill Training Across Questionnaire Sections

Comparable types of training data collected within various sections of the questionnaire, the "Government Training," "Jobs," "Military," "Training," or "Other Training" sections, have been grouped together in Table 3. Variables represented in the table include those that have the following types of training represented either within their variable title or as a coding category: 

• basic skill training
• occupational skill training (classroom)
• occupational skill training (on-the-job)
• or occupational skill training (apprenticeship program)

Employer-specific training: Questions on employer-specific training were fielded during select survey years and are also included in Table 3. 

Table 3.  "Other Training" & "Training" Sections of the NLSY79 for All Survey Years

Comparison to Other NLS Cohorts: In each survey, information has been collected from the NLSY79 young adults, on their participation in training programs. For the young adults, government sponsorship of a training program is incorporated within the regularly asked "Other Training" questions. Beginning in 2000, detailed information was asked only of the current or most recent training program.

The NLSY97 asks all respondents who were at least 16 years old whether they had ever participated in any occupational training programs outside of their regular schooling. For each program, the survey then collects basic information, including the type of program, start and stop dates, time devoted to the training, periods of nonattendance lasting a week or longer during training sessions of at least two weeks, and whether the program was completed (and if not, the reason). In each round, respondents were asked about whether they participated in government training programs. Additional questions asked for specific programs and their duration.

Original Cohort respondents were asked questions about training both on and off the job and focused on government training programs. For the Young Men, details concerning training received in the military (other than basic training) were gathered in the 1966, 1969, 1971, 1976, and 1981 surveys. In 1975, among other additions, a new provider, "government program or agency", was added to the "Training" section of the Young Women survey. Beginning in 1984, a new category, "government agency", was added to the "Training" section of the Mature Women survey. For more precise details about the content of each survey, consult the appropriate cohort's User's Guide using the tabs above for more information.

References

Loewenstein, Mark A. and Spletzer, James R. "Informal Training:  A Review of Existing Data and Some New Evidence." NLS Discussion Paper No. 94-20.  Washington, DC: Bureau of Labor Statistics, U.S. Department of Labor, 1994.

National Center for Research in Vocational Education and Center for Human Resource Research. NLSY High School Transcript Survey: Overview and Documentation.  Columbus, OH: CHRR, The Ohio State University.

Pollard, Tom. "An Overview of the Post School Vocational Training Experiences of Youth." In Pathways to the Future. A Report on the National Longitudinal Survey of Youth Labor Market Experience in 1979. Michael E. Borus, ed. Columbus, OH: CHRR, The Ohio State University, 1981.

The 1980 survey included several questions on school discipline problems, that is, whether NLSY79 respondents had ever been suspended or expelled from school, and if so, the number of times, date of most recent disciplinary action, and when/if the youth had returned to school. Almost one quarter of the sample, or 3,030 respondents, reported having been suspended at some point in their schooling; a smaller number (538) reported having been expelled. 

The "Regular Schooling" sections of each questionnaire collect information on the reason why nonenrolled respondents, who had been enrolled in school since the last interview but who had left school before the current interview, had left school. "Expelled or suspended" is a possible response to this question. Although a distinction cannot be made between expulsions and suspensions, a record of the dates that a respondent left school because of an expulsion/suspension and the dates that school was reentered can be constructed between survey years by linking information collected in these sections of the NLSY79 questionnaire.

Comparison to other NLS Cohorts 

Information was collected on behavior problems evidenced by children of NLSY79 respondents that resulted in either the parent's notification or disciplinary action. NLSY97 respondents are asked whether they have been suspended and, if so, for what periods. The Young Women and the Young Men surveys ask respondents whether they have ever been suspended or expelled from school. For more precise details about the content of each survey, consult the appropriate cohort's User's Guide using the tabs above for more information.

Separately administered surveys collected information from the high schools attended by respondents in the NLSY79 cohort. This included special transcript data collections that gathered, from the high school records of respondents, detailed information on courses taken, grades, and credit received.

NLSY79 High School Survey

A separate mail survey of the schools attended by civilian NLSY79 respondents was conducted during 1980. Schools eligible for survey were U.S. schools attended by civilian respondents who had both been interviewed in 1979 and completed the 1979 "School and Record Information Release Form." A follow-up release form, the "Student Release/Locating Form," was administered by Profile of American Youth examiners during the summer of 1980--2,200 forms were collected. Designed to supplement both subjective respondent information on educational experiences collected during the main surveys and the transcript data collections described below, the school survey gathered information on:

• each school's total enrollment
• type of grading system
• number of books in the school library
• vocational/technical course offerings
• dropout rate
• percent of economically disadvantaged students
• characteristics/qualifications of the staff
• percentage average daily attendance

Also collected was respondent-specific information for the school surveyed including:

• month/year last enrolled
• reason not enrolled
• highest grade attended
• whether the respondent had participated in remedial English, remedial mathematics, English as a second language, or bilingual education classes

Scores from intelligence and aptitude tests administered to the youth during his or her schooling were also collected. Table 1 in the Aptitude, Achievement & Intelligence Scores section of this guide presents the names of the tests and the numbers of respondents for whom scores are available.

NLSY79 Transcript Surveys

During 1980-83, transcript information was collected for 8,778 civilian NLSY79 respondents who were 17 years of age or older and who were expected to complete high school within the United States. The types of information gathered for each of up to 64 courses included:

• grade level at which the course was taken
• a code for the high school course
• the final or computed grade for that course
• the source of the final grade
• the credits received

Rumberger and Daymont (1982) review the types of academic and vocational courses reported during the initial transcript fielding effort.

Additional information collected from each school for each surveyed respondent included:

• number of days the respondent was absent from school in each of the high school grades attended
• the respondent's rank in class for the last year attended
• number of students in the respondent's class for the last year attended
• dates (month/year) last enrolled at this school
• reason left this school

Be aware that these data have high nonresponse rates. In some cases, individual items are only available for small numbers of youth.

Summary variables include the final transcript disposition status, the year in which these transcript data were collected, and an error flag for these transcript data. Scores (math and verbal) from standardized tests collected during this special survey are discussed in the Aptitude, Achievement & Intelligence Scores section. Table 1 depicts fielding periods, target samples, and the number of eligible respondents for each of the transcript fielding efforts.

References

National Center for Research in Vocational Education and Center for Human Resource Research. NLSY High School Transcript Survey: Overview and Documentation. Columbus, OH: CHRR, The Ohio State University.

NORC. "The School and Transcript Survey: Technical Report." Chicago: NORC, University of Chicago, 1980.

NORC. "Transcripts II: Technical Report." Chicago: NORC, University of Chicago, 1982.

NORC. "Transcripts III: Technical Report." Chicago: NORC, University of Chicago, 1984.

Rumberger, Russell and Daymont, Thomas N. "The Effects of High School Curriculum on Labor Market Success." In Pathways to the Future, Volume II. A Final Report on the National Longitudinal Survey of Youth Labor Market Experience in 1980. Michael E. Borus, ed. Columbus, OH: CHRR, The Ohio State University, 1982.

The following three surveys, conducted independently of the regular NLSY79 interviews, collected aptitude and intelligence score information:

• Armed Services Vocational Aptitude Battery (ASVAB), a special survey administered in 1980 to the 1979 sample of NLSY79 respondents (see Table 1)
• High School Survey, a 1980 survey of high schools, which used school records to collect scores from various aptitude/intelligence tests and college entrance examinations administered during the youth's high school career (see Table 1)
• Transcript Survey, a 1980-83 collection of high school transcript information, which included the gathering of math and verbal scores from such tests as the Preliminary Scholastic Aptitude Test (PSAT), the Scholastic Aptitude Test (SAT), and the American College Test (ACT) (see Table 1)

Additionally, an abbreviated version of the "Knowledge of the World of Work" scale was directly administered to the young men and women of the NLSY79 as an assessment in 1979.

ASVAB administration

During the summer and fall of 1980, NLSY79 respondents participated in an effort of the U.S. Departments of Defense and Military Services to update the norms of the Armed Services Vocational Aptitude Battery (ASVAB). The Department of Defense and Congress, after questioning the appropriateness of using the World War II reference population as the primary basis for interpreting the enlistment test scores of contemporary recruits, decided in 1979 to conduct this new study. NLSY79 respondents were selected since they composed a nationally representative sample of young people born during the period 1957 through 1964. This testing, which came to be referred to as the "Profile of American Youth," was conducted according to standard ASVAB procedural guidelines.

Profile of American Youth

• Respondents were paid $50.
• Five to ten persons were tested at more than 400 test sites, including hotels, community centers, and libraries throughout the United States and abroad.
• 11,914 civilian and military NLSY79 respondents (or 94 percent of the 1979 sample) completed this test including:
  • 5,766 or 94.4 percent of the cross-sectional sample.
  • 4,990 or 94.2 percent of the supplemental sample.
  • 1,158 or 90.5 percent of the military sample.

The ASVAB consists of a battery of 10 tests that measure knowledge and skill in the following areas:

• general science
• arithmetic reasoning
• word knowledge
• paragraph comprehension
• numerical operations
• coding speed
• auto and shop information
• mathematics knowledge
• mechanical comprehension
• electronics information

The following variables are available for each youth tested:

• raw scores
• scale scores
• standard errors
• sampling weight
• high school graduation status
• whether the test was completed under normal or altered testing conditions

A composite score derived from select sections of the battery can be used to construct an approximate and unofficial Armed Forces Qualifications Test score (AFQT) for each youth. The AFQT, developed by the U.S. Department of Defense (DOD), is a general measure of trainability and a primary criterion of enlistment eligibility for the Armed Forces. Three AFQT percentile scores, an AFQT-1, AFQT-2 and an AFQT-3, were created for each Profiles respondent and are described below.

AFQT-1

To construct AFQT-1, the raw scores from the following four sections of the ASVAB are summed:

• Section 2 (arithmetic reasoning),
• Section 3 (word knowledge),
• Section 4 (paragraph comprehension),
• and one half of the score from Section 5 (numerical operations).

AFQT-2

Beginning in January 1989, DOD began using a new calculation procedure. The numerical operations section of the AFQT-1 had a design inconsistency resulting in respondents getting tests that differed slightly and resulted in slight completion rate differences.

Creation of this revised percentile score, called AFQT-2, involves:

• computing a verbal composite score by summing word knowledge and paragraph comprehension raw scores;
• converting subtest raw scores for verbal, math knowledge, and arithmetic reasoning;
• multiplying the verbal standard score by two;
• summing the standard scores for verbal, math knowledge, and arithmetic reasoning;
• converting the summed standard score to a percentile.

AFQT-3

In 2006 the AFQT-2 scores were renormed controlling for age so that the AFQT can be used comparatively with the NLSY97. For this reason NLS staff recommend using the AFQT-3. Although the formula is similar to the AFQT score generated by DOD for the NLSY79 cohort, this variable reflects work done by NLS program staff and is neither generated nor endorsed by DOD.

To calculate the AFQT-3, NLS Program staff first grouped respondents into three-month age groups. That is, the oldest cohort included those born from January through March of 1957, while the youngest were born from October through December 1964, a total of 32 cohorts, with an average of about 350 respondents per cohort (there was one unusually small cohort: the youngest cohort has only 145 respondents). The revised dates of birth from the 1981 survey (R0410100 and R0410300) were used whenever these disagreed with the information from the 1979 survey. With the revised birth dates, a few respondents were born outside the 1957-1964 sampling space of the survey.

Those born before 1957 were assigned to the oldest cohort, while those born after 1964 were assigned to the youngest cohort. ASVAB sampling weights from the Profiles section were used (R0614700). Within each three-month age group and using the sampling weights, staff assigned percentiles for the raw scores for the tests on Mathematical Knowledge (MK), Arithmetic Reasoning (AR), Word Knowledge (WK), and Paragraph Comprehension (PC) based on the weighted number of respondents scoring below each score (ties are given half weight). Staff added the percentile scores for WK and PC to get an aggregate Verbal score (V) for which an aggregated intra-group, internally normed, percentile was then computed. NLS Program staff then added the percentile scores for MK, AR and two times the aggregated percentile for V. Finally, within each group we computed a percentile score, using the weights, on this aggregate score, yielding a final value between zero and 100. Note there are three implied decimal places.

Data recovery

Based on a search of archival files and an examination of the original ASVAB score sheets, revised correct/incorrect indicators based on the answer key and hard copy were generated for the four tests used for the AFQT -- Paragraph Comprehension (PC), Word Knowledge (WK), Arithmetic Reasoning (AR) and Mathematics Knowledge (MK). Consequently, the variables in the newly released AFQT answer file will, for some respondents, show a different number of correct answers than in the original scoring for these tests.

Item response theory norms for the AFQT

Additional norms for the AFQT scales (PC, WK, AR, and MK) were created using Item Response Theory (IRT) theta scores from the three-parameter logistic model (3PL). IRT jointly estimates item scores and respondent scores via fixed effect estimation. The three parameter logistic model (3PL) also estimates a guessing parameter for each item. Based on evidence from factor analyses of the unidimensionality of pooled Paragraph Comprehension and Word Knowledge, as well as Arithmetic Reasoning and Mathematics Knowledge, IRT theta scores were also generated for the combined math (AR and MK) and combined verbal (WK and PC) scales. These pooled tests should give better resolution of these two domains.

The IRT theta scores were used to create norms for PC, WK, AR, MK and the combined math and verbal scales. In norming these tests, respondents were grouped into four-month age intervals for each birth year. By breaking the norming step into 24 cohorts, we avoid the risk that some might conclude younger respondents have less native ability than older respondents. Within each age group, IRT theta scores were ranked from lowest to highest. Using the ASVAB sampling weights, percentiles were calculated based on the weighted number of respondents scoring below each respondent.

Additional details can be found in Appendix 24: Reanalysis of the 1980 AFQT Data from the NLSY79.

References

Bock, R. Darrell and Moore, Elsie G.J. Advantage and Disadvantage: A Profile of American Youth. Hillsdale, NJ: Lawrence Erlbaum Associates, 1986.

U.S. Department of Defense. "Profile of American Youth: 1980 Nationwide Administration of the Armed Services Vocational Aptitude Battery." Washington, DC: Office of the Assistant Secretary of Defense (Manpower, Reserve Affairs, and Logistics), March 1982.

U.S. Department of Defense. "Profile of American Youth: 1980 Nationwide Administration of the Armed Services Vocational Aptitude Battery." Washington, DC: Office of the Assistant Secretary of Defense (Manpower, Reserve Affairs, and Logistics), March 1982.

High School Survey

During April through October 1980, a separate survey was conducted of U.S. high schools attended by civilian NLSY79 respondents. This school survey obtained information about the characteristics of each school. It also gathered respondent-specific information that included scores from various intelligence and aptitude tests administered during the respondents' schooling.

Data are available for tests such as the:

• California Test of Mental Maturity
• Differential Aptitude Test
• Stanford-Binet Intelligence Scale
• Wechsler Intelligence Scale for Children

A variety of other tests are available including college entrance examinations such as the:

• Preliminary Scholastic Aptitude Test (PSAT)
• Scholastic Aptitude Test (SAT)
• American College Test (ACT)

The following types of information are available for each test taken: 

• IQ score
• national percentile score
• date (month/year) the test was administered
• student's grade level at the time of testing

A modest number (1,058 or 9.1 percent) of civilian NLSY79 respondents has one or more such scores available from the high school survey; additional scores may be available from the transcript survey.

Transcript surveys

High school transcript information was collected during 1980, 1981, and 1983 for those civilian respondents who were expected to complete high school in the United States. While the focus of these surveys was course and grade information, math and verbal scores from the PSAT, the SAT, and the ACT were also collected. One or more (sub)scores for at least one test are available for 2,434 (21.3 percent) of civilian NLSY79 respondents. Additional information, including references to technical reports on these surveys, can be found in the School & Transcript Surveys section of this guide.

Table 1 provides an alphabetical listing of the tests from the high school, and transcript surveys and the number of respondents for whom scores are available.

References

National Center for Research in Vocational Education and Center for Human Resource Research. NLSY High School Transcript Survey: Overview and Documentation. Columbus, OH: CHRR, The Ohio State University.

Parnes, Herbert S. and Kohen, Andrew I. "Occupational Information and Labor Market Status: The Case of Young Men." Journal of Human Resources. 10 (1): 44-55, 1975.

Parnes, Herbert S., Miljus, Robert C. and Spitz, Ruth S. Career Thresholds: A Longitudinal Study of the Educational and Labor Market Experience of Male Youth. Vol. I. U.S. Department of Labor Manpower Research Monograph No. 16. Washington, DC: U.S. Government Printing Office, 1970.

Knowledge of the World of Work

One assessment, an abbreviated version of the "Knowledge of the World of Work" scale, was directly administered to the young men and women of the NLSY79 in 1979. This set of questions (R00260.-R00268.) asks respondents to pick one of three statements that best describes the duties of each of 10 commonly held jobs. A total score can be calculated by awarding one point for each correct answer (Kohen and Breinich, 1975; Parnes and Kohen, 1975; Parnes, et al., 1970).

This question has an age restriction in that all respondents were asked questions concerning their thoughts on certain kinds of jobs that people actually do. Respondents who were 14-15 years old were skipped out at Q.2. 

Information on NLSY79 respondents' educational experiences has been collected during each survey year. In addition, three special data collections conducted during 1980-1983 gathered the following for select universes: 

• supplementary information on degrees and certifications received as of the 1980 survey
• detailed information on the amount of time spent at school on each of the past seven days and the amount of time spent in various school-related activities, such as attending classes, studying, participating in other activities
• high school course information gathered (directly from school records) during the 1980-1983 transcript surveys

Table 1 summarizes the major types of NLSY79 educational status and attainment variables and identifies the survey years during which such data were collected.

Armed Forces sample

During the 1979-1985 surveys, respondents who had served in the Armed Forces since the last interview or were serving at the current interview date were asked a series of questions on high school or college courses taken and years of school completed while in the Armed Forces.