Glossary of NLS Terms

Glossary of NLS Terms

These terms are pertinent to all or a portion of the NLS project, including the NLSY97, NLSY79, Children of the NLSY79, NLSY79 Young Adults, and the Original Cohorts.

A   B   C   D   E   F   G  H   I   J   K   L   M   N   O   P   Q   R   S   T   U   V   W   X   Y   Z


Active forces
An umbrella term used to refer to the regular branches of the Armed Forces (Army, Navy, Marines, and Air Force) as a group.

Active job search
An active job search is one that could have resulted in a job offer without further action on the part of the job seeker.  Methods include:

  • Contacting public employment agency
  • Contacting private employment agency
  • Contacting employer directly
  • Sending out resumes or filling out applications
  • Contacting friends or relatives
  • Contacting school/college or university employment center
  • Placing or answering ads
  • Checking union/professional registers
  • Other active method (for example, bid on a contract)

See also Passive Job Search

Adult basic education
This is remedial education, such as basic literacy or math skills, which does not include work directed toward passing the GED test. 

Aid to Families with Dependent Children (AFDC); Aid to Dependent Children (ADC)
Commonly referred to as welfare, these two federal programs help families with dependent children by providing financial assistance each month.  Eligible children are from low-income households and lack support of one or both parents.  Since the implementation of welfare reform, these programs have been replaced by the TANF (Temporary Assistance for Needy Families) program on the state or county level. 

Air Force Specialty Codes (AFSC)
An alphanumeric jobs/skills classification system for the Air Force and Air Force Reserves that describes the specific job a person is trained for or assigned to in those branches of the military.  (See also DOD-3-Digit.)

A type of asset that provides a fixed payment each month or year until a person dies.  Most pensions are annuities; annuities can also be purchased directly from insurance companies.  Types of annuities include the following:  deferred annuities, fixed annuities, variable annuities, immediate annuities, and annuity certains. 

Any word search
This search function in NLS Investigator allows users to select any word or words and to view all variables that contain those words in their titles.

Apprenticeship program
A formal program in which a person agrees to work in a skilled trade or art in return for wages and training for a prescribed period of time. 

Area of Interest
In NLS Investigator, the Area of Interest search function provides a list of variables grouped by common topical areas. 

Armed Forces Qualifications Test (AFQT)
The AFQT determines general aptitude for enlistment in the Armed Forces. It is computed using some of the ASVAB tests. Two methodologies of calculating AFQT, developed by the U.S. Department of Defense, have been used to produce two AFQT variables in the NLSY79:  R06182. (AFQT80) and R06183. (AFQT89).  R06182. is the AFQT percentile score created from the procedures in use in 1980 and consists of the sum of the number of correct scores for the following sections of the ASVAB:  arithmetic reasoning + word knowledge + paragraph comprehension + ½ (numerical operations).  R06183. is the AFQT percentile score based on new procedures established in 1989 and is created in the following manner: (1) compute a verbal composite score by summing the word knowledge and paragraph comprehension raw scores; (2) convert subtest raw scores to standard scores for verbal, math knowledge, and arithmetic reasoning; (3) multiply verbal by 2; (4) sum the standard scores for verbal, math knowledge, and arithmetic reasoning; and (5) convert the summed standard score to a percentile.  A third revised AFQT score variable (R06183.01) was added in 2006. See the NLSY79 Addendum to Attachment 106 for tables used to convert raw scores to standard scores and percentiles. In addition, the NLSY97 has an AFQT-like variable:  ASVAB_MATH_VERBAL_SCORE_PCT.

Armed Services Vocational Aptitude Battery (ASVAB)
This test measures the applicant's knowledge and skills in a number of topical areas and is used by the military to produce a general standard of trainability and enlistment eligibility for the Armed Forces.  The ASVAB was administered to NLSY79 respondent in 1980. The computer adaptive form of the test, the CAT-ASVAB, was administered to NLSY97 respondents during round 1. This test was sponsored by the Department of Defense. Portions of the ASVAB are used to create the AFQT score.

Armed Forces
This includes the active forces, the reserves, and the guard.  Please note that civilian employees of the Armed Forces are considered federal employees.

Audio computer-assisted self-interview (ACASI)
Self-administered portions of NLSY97 instruments use an ACASI system that allows the respondent to listen to the questions and response categories being read over headphones.  ACASI sections can be heard in either English or Spanish.


Behavior Problems Index (BPI)
NLSY79 mothers are asked 28 questions about specific behaviors that their children age four and over may have exhibited in the previous three months.

A bonus is a sum of money or an equivalent (stocks, company shares) given in addition to usual compensation, normally for outstanding performance and service. See also Commission and Tips.

Bureau of Labor Statistics (BLS)
This agency of the U.S. Department of Labor sponsors and oversees the National Longitudinal Surveys project.

A business exists when one or more of the following conditions is met:  (1) machinery or equipment of substantial value is used in conducting the business; (2) an office, store, or other place of business is maintained; or (3) the business is advertised by listing in the classified section of the phone book, displaying a sign, distributing cards or leaflets, or otherwise publicizing that the work or service is offered to the general public.

Business school
A training program that provides the trainee with business skills, not to be confused with business classes in college or graduate school.  This type of program does not contribute to an undergraduate or professional degree.


See Armed Services Vocational Aptitude Battery (ASVAB).

Center for Human Resource Research (CHRR)
CHRR is a research unit at The Ohio State University that conducts the NLS in partnership with NORC at the University of Chicago.  CHRR's roles include design, management, variable creation, documentation, dissemination, and user services. 

Certificate of deposit (CD)
A certificate of deposit or a savings certificate is issued for a specific deposited amount at a fixed rate of interest for a given time period.  Certificates can be issued by a bank, credit union, or savings & loan association. There is usually a required minimum deposit; the maturity period can vary from a few weeks to several years; there is a penalty for early withdrawal; and deposits are usually insured.

Center for Epidemiologic Studies Depression Scale.  This scale is designed to measure symptoms of depression in the general population.

Check item
Check-item questions are found in the survey questionnaire and are used during the course of the interview to identify the sample universe and denote the skip pattern for a particular set of questions. These questions are answered based on previous responses or direct observations, without asking the respondent.

Children of the NLSY79
This survey group comprises all children born to female NLSY79 respondents.  The group was first surveyed in 1986 and has been reinterviewed biennially.  Since 1994, a separate survey has been administered to children age 15 and older, referred to as the Young Adults.

After a user extracts data from the NLS Investigator, they see a codeblock, which provides information about each variable presented in a consistent form. Most codeblocks provide users with the variable title, reference number, question number, survey year, coding information, and a frequency distribution.

In the NLS Investigator software, the codebook contains complete information about all the variables in a data set.  It comprises a number of codeblocks presenting information about each variable.

A cohort is a group of people who share similar characteristics at a particular point in time. The NLS project consists of multiple cohorts, including the Original Cohorts (Older Men, Mature Women, Young Men, and Young Women), the NLSY79, the NLSY97, the Young Adult and the Children of the NLSY79

Collateral includes property, goods, or other assets which must be pledged as part of a loan.  If the borrower defaults on the loan, the lender has the right to "foreclose on" (take) the collateral.

College or university
A college or university is an educational institution that gives credit toward an academic degree at the post-secondary and/or post-graduate levels.  A college or university offers candidates an associate's, bachelor's, master's, or doctoral degree in a specific academic concentration.

A commission is an amount or percentage of money that is given in addition to one's regular salary.  In some jobs, usually sales, the base pay may be quite low, with most of a person's earnings in the form of commissions. See also Bonus and Tips.

Community or junior college
These colleges provide courses that may result in a 2-year or associate's degree; these courses are considered regular school.  If the courses are taken to improve job skills and do not count toward an academic degree, these courses are considered training rather than regular schooling.

Computer-assisted personal interview (CAPI)
These interviews are administered using a survey instrument on a laptop computer. The early NLS surveys were traditional paper and pencil interviews (PAPI). The NLSY79 switched to using CAPI instruments in 1993, while the Women cohort surveys begin using a CAPI instrument in 1995. The NLSY97 used CAPI instrumentation from the start. CAPI allows for more complex questionnaire programming, bounded interviewing, and faster data dissemination than with PAPI interviews.

Created variables
Created variables, part of the NLS data variables available in the NLS Investigator, summarize complex series of respondent questions into one measure, such as hourly wage for employer 1 in 2000. The components for the created variable may be based on information provided by the respondents or obtained from other outside sources. They are created by survey staff after the interview.

Current Population Survey (CPS)
Conducted by the Census Bureau, the CPS is a series of monthly interviews that collects up-to-date information about the number of persons in the country who are employed, unemployed, or not in the labor force in a specific survey week. Labor force status questions included in select rounds of the NLSY79 and NLSY97 were the same as the CPS questions used to determine employment status and were administered as closely as possible to the method used by the Census Bureau so that findings are comparable. A respondent's current/most recent (main) job is sometimes referred to as a "CPS job."

CVC variable
In the NLSY97, if a created variable has "CVC_" as its question name prefix, it is a special type of created variable created from information from all rounds of the survey, regardless of whether or not the NLSY97 respondent was interviewed for a particular round.


Date of Last Interview (DLI)
DLI, which stands for "date of last [most recent] interview," is a common abbreviation found in NLS question titles.  Because an NLSY respondent may not be able to interview each survey year, many questions are designed to pick up information all the back to the respondent's previous interview. Similar abbreviations include SDLI (since date of last interview), LINT (last interview), and PDLI (prior to date of last interview).    

Delayed Entry Program (DEP)
A program that allows a person to enlist in the military and then report for active duty at a later time (as many as 365 days later).  Individuals enlisting through this program are sworn into their military branch on two occasions:  once at the time that they enlist through DEP and a second time when they actually begin active duty.  DEP enlistees do not always report for active duty and can be guaranteed, in writing, the type of training and the location that they want.

Dictionary of Occupational Titles (DOT)
This occupational directory was developed by the Department of Labor as a comprehensive classification system for occupations.  It was used to code NLSY79 respondents' 1979 current occupation only.  The individual occupations are identified by the 1970 9-digit DOT codes.

Dividend payments, usually in the form of money or stock, are paid to shareholders of a corporation or some other cooperative society or membership club.  The dividend amount is decided by the board of directors and is usually paid on a quarterly basis.  Dividends must be declared as income in the year they are received.

A codebook abbreviation for the "Don't Know" answer a respondent may give.

An occupation code using the 1977 Department of Defense 3-Digit Enlisted Occupational Classification System.  This numeric coding scheme standardizes the occupational coding across all branches of the military. 

Duncan Index
An ordinal measure of socioeconomic status that assigns a two-digit prestige score to the Census occupation codes. The index scores are based on education and income distribution ratings and range from 0 to 97.  (See Otis Dudley Duncan. " Socioeconomic Index for all Occupations." In Occupations and Social Status, Reiss, Jr., A.J., et. al., New York:  The Free Press of Glencoe, 1961).

Dwelling Unit (DU)
A single room, or group of rooms, that is intended for separate living quarters.  To be considered a separate dwelling unit, it must have either a separate entrance or complete kitchen facilities (stove, sink with piped water, and refrigerator) for the sole use of the household.


Educational Tuition Assistance Program (ETAP)
The educational benefit package for the Armed Forces Reserves.  It is comparable to VEAP.

See Labor Force and Employment Status.

Employee-type job
An employee-type job is one in which an individual is working as an employee; that is, he or she has an on-going relationship with a particular employer. See also Freelance Job.

Employer Supplement
The Employer Supplement is an addition to the NLSY79 youth cohort survey instrument. One supplement is completed for each employer a respondent has had since the date of the last interview.  The 1979 interview incorporated five columns in Section 10 of the survey instrument; each column is equivalent to one Employer Supplement. In the NLSY97, the distinction between the employer section and an employer supplement is not made.

Employment Status Recode (ESR)
ESR is a variable created from information collected on employment status in the week before the survey. It provides a standardized employment status code for each member of the sample. It is available for select rounds of the NLSY97 and NLSY79.

Enumeration Districts
Enumeration districts (ED) are areas used in the geographic control of enumeration activities by the Census Bureau.  An ED is the territory assigned to a single enumerator to cover during a census count.

Environmental Variables
County and State codes are assigned for all geographic locations according to the Federal Information Processing Standards (FIPS-5.)  The codes for the respondent's current residence at each interview date are then matched with the 1972, 1977, 1983, 1988, and 1994 City and County Data Books (depending on survey year) to obtain characteristics of the county such as population size, crime statistics, and industrial diversification. (see specific survey year).  These data are available on the Geocode CD to approved researchers.

The assets, debts, and property left by someone at the time of his or her death.  Life insurance proceeds are generally added to the estate.

Even Start
Federally funded program that provides families with early childhood education for their young children, adult education for parents, and parenting education and support.

Event History variables
Weekly/monthly/yearly variables created from respondent-reported survey data. These variables, available to the public in the NLS Investigator, generally give the status (such as employed, participating in a government program, enrolled, married) of the respondent for each time unit from a specific date (usually the 14th birth year) to the latest interview date.

Expulsion occurs when a student is permanently prohibited from attending a learning institution, usually due to misconduct or breaking the school's rules. See also Suspended.


An abbreviation for field interviewer.

Freelance job
A type of employment where the individual does not have long-term commitments to any one employer.  The individual can act independently without regard or deference to authority.  The freelancer may work on one or more tasks for several people and does not have a "boss" (for example, baby-sitting or mowing lawns), or the freelancer may work for himself or herself (for example, running a business). See also Employee-type job.

Futures contract
A purchase of the right to buy or sell commodities, such as wheat, corn, and cocoa, at a specific point in the future.  These contracts are traded on futures exchanges like the Chicago Board of Trade. (Not included in survey help screens; listed here for user reference.)


General Educational Development Test, General Equivalency Diploma (GED)
A certificate, considered by some to be an equivalent to a high school diploma, which is obtained as a result of taking the General Educational Development Test or GED.  The test provides a valid means of measuring the educational proficiency of individuals taking the test in comparison with high school graduates.  (Also known as a general equivalency diploma.)

Geographic codes, published by the National Bureau of Standards as the Federal Information Processing Standards (FIPS), are assigned to respondents' residences.  They can be used to match NLS data with other data (e.g., City and County Data Books).  To preserve respondent confidentiality, geocode data are available only to researchers who satisfactorily complete a BLS accessing agreement. 

Government employee
A government employee can be one of three types:  federal, state, or local.  Respondents are classified according to the following definitions:

  • Federal government employees are respondents working for any branch of the federal government, including those elected to paid federal offices, civilian employees of the Armed Forces, and some members of the National Guard.  Employees of international organizations (e.g., United Nations) and employees of foreign governments (e.g., the French Embassy) are also included.
  • State government employees include paid state officials, state police, and employees of state universities and colleges.
  • Local government employees are respondents employed by cities, towns, counties, and other local areas, including employees of city-owned businesses, water and sewer services, etc.  Employees of public elementary and secondary schools also work for the local government.

Government training
Training sponsored by the government for the general public (e.g., JTPA, Job Corps).  Note that training sponsored by the government for its employees (e.g., Police Academy, computer courses) is considered company training.

Gross Income
Gross income for all nonfarm businesses and professions is defined as all monies received from the sale of goods or for services rendered, as well as the amount of net inventory increase.  It does not include proceeds from the sale of capital items such as land, buildings, and machinery.  For farms, it is defined as all monies received from the sale of farm products, government subsidies on crops and soil conservation, and income from rental of equipment.  It does not include the value of any farm products (such as food and fuel) used by the family or proceeds from the sale of land, buildings, or machinery.


Head Start
Head Start is a federally funded program that provides comprehensive developmental services for disadvantaged, low-income children from birth until they reach school age.

Home equity loan
Any loan which uses the collateral of a person's home and which has a fixed number of payments and a fixed amount borrowed.

Household Income Update
This one-page paper instrument, administered to a parent of those NLSY97 respondents still living at home, collected information in rounds 2-5 about the income of the parent and his or her spouse or partner.

Household unit
A single room, or group of rooms, that is intended as separate living quarters for a family, a group of unrelated persons living together, or for a person living alone.

Household Screener
This survey was administered in late 1978 to the initial sample of NLSY797 households to locate eligible respondents for the NLSY79 civilian sample.  Approximately 75,000 households were screened to identify eligible respondents based on age, sex, ethnicity, and poverty status. A similar screener was administered to households prior to the start of the NLSY97 to locate eligible respondents for the main survey.


Incentive pay
In some jobs, employees receive extra money or other compensation for reaching or exceeding certain levels of performance, such as meeting established sales quotas in a given month or year.

Independent youth
In the NLSY97, an independent youth is a respondent with at least one of the following characteristics:  is age 18 or older, has had a child, is enrolled in a 4-year college, has ever been married or is in a marriage-like relationship at the time of the survey, is no longer enrolled in school, or is living outside his or her parent-figure's home.

Individual Quarters (IQ)
A term used to describe nondwelling unit, noninstitutional living quarters.

Individual Retirement Account (IRA)
An Individual Retirement Account is a personal, tax-advantaged savings account to which any individual under 70 1/2 years of age can transfer funds to save and invest for retirement. The earnings are tax deferred until drawn upon. One can begin withdrawing from his or her IRAs after age 59 1/2; withdrawals prior to this age are generally subject to a tax penalty.

Industry Census code (NLSY97)
A 3-digit numeric code from the 1990 Industrial Classification System (in early rounds) and the 2002 Industrial Classification System (in more recent rounds) used by the Census Bureau to assign codes to industries (Census Bureau. 1990 Census of Population Alphabetical Index of Industries and Occupations.  Washington, DC:  U.S. Government Printing Office, 1991;

Industry Census Code (NLSY79)
A 3-digit numeric code from the Industrial Classification System used by the Census Bureau to assign codes to industries.  The 1970 system consists of 215 industry categories arranged into 12 major groups.  It was developed within the framework of the Standard Industrial Classification (SIC).  The 1970 Census classification system is used to code industry information from the 1979-2000 surveys; industries of a respondent's most recent job identified during the 1982-2000 NLSY79 surveys are doublecoded with the 1970 and 1980 Census codes. Beginning with the 2002 NLSY79 survey all occupations and industries were coded with 2000 codes only.

Information Sheet (NLSY79)
An Information Sheet, which lists pertinent informational items about the respondent that were collected during the previous interview is provided to NORC interviewers.  Info sheet items include date of birth, marital status, date of last interview, and so forth. In PAPI surveys, the interviewers referred to the information sheet during the course of the interview in order to ascertain possible updates. The automated CAPI instruments access it automatically to drive the survey.

Money or property that is legally transmissible to an heir is considered inheritance.

This is an abbreviation for interview.

Int. Check
Interviewer check questions are used during the course of the interview to check the sample universe and denote the skip pattern for a particular set of questions.  The interviewer codes the question based on previous responses or direct observation, without asking the respondent.

Interest on Savings and U.S. Savings Bonds
Includes interest accrued from savings accounts even if the money has been withdrawn.  It does not include interest on unredeemed U.S. Savings Bonds; if the bonds were cashed, only the difference between the amount received and the original cost is considered.

International Classification of Diseases (ICD)
The ICD is a coding system for diseases, injuries, and causes of deaths as adopted by the World Health Assembly.  The coding system used is defined in the International Classification of Diseases, 9th Revision, 1975, with some minor modifications.


Job Characteristics Index.

A job exists when there is a definite arrangement for regular work every week, or every month, for pay or other compensation (e.g., profits; anticipated profits; or pay "in kind" such as meals, living quarters, or supplies received in lieu of cash from someone other than a family member). A formal, definite arrangement with one or more employers to work on a continuing basis for a specified number of hours per week or days per month, but on an irregular schedule during the week or month, is also a job.  Generally speaking, any job that is usually 35 hours or more per week is considered full-time. In some occupations (for example, air traffic controllers), usual weekly schedules of less than 35 hours per week are considered to be full-time.

Job Corps
A program designed to assist economically disadvantaged young men and women who need and can benefit from an intensive educational and vocational training program.  The intent is to help them become more responsible, employable, and productive citizens. The program is operated in a residential group setting.

Job search
To be considered as looking for work a person must have conducted an active search for a job within the four weeks prior to the interview week. See Active Job Search and Passive Job Search.

Job Training Partnership Act (JTPA)
Legislation enacted in the fall of 1983 authorizing federal funds for employment and training. The emphasis is on private sector participation in training, without subsidies for the training participants.


"Knowledge of the World of Work"
The nine multiple-choice items that test the respondent's ability to determine the duties associated with selected occupations.


Labor Force and Employment Status
All civilian respondents who were either employed or unemployed during the survey week are defined as being in the labor force. Employed, unemployed, and out of the labor force are defined as follows:

  • Employed: All respondents who during the survey week were either (1) at work-those who did any work for pay or profit or worked without pay for 15 hours or more on a family farm or business-or (2) with a job but not at work-those who did not work and were not looking for work, but had a job or business from which they were temporarily absent because they were taking time off for various reasons-are classified as employed.
  • Unemployed: All respondents who did not work at all during the survey week and either (1) were looking or had looked for a job in the four-week period prior to the survey; (2) were waiting to be recalled to a job from which they had been laid off; or (3) were waiting to report to a new job within 30 days are considered to be unemployed.
  • Out of the Labor Force (OLF): All respondents who were neither employed nor unemployed during the survey week are considered to be out of the labor force.

Land contract
Also known as a conditional sale agreement.  A contract between a property owner and a potential purchaser, where they agree on the price of the home and the purchaser moves into the property.  However, the seller retains legal rights to the property.  The buyer makes regular monthly payments, which in some cases complete the sale of the property.  In other cases, there is a large balloon payment due which completes the sale.  These are often used when the buyer does not have enough money for a down payment.

Respondents are classified as on layoff if they are waiting to be recalled to a job from which they were temporarily separated for business-related reasons, such as temporary drops in demand, business downturns, plant remodeling, material shortages, and inventory taking.  They must either have been given a date to report back to work or expect to be recalled to their job within six months.

Longitudinal study
A longitudinal study follows the same group of individuals over an extended period of time. The NLS project is a collection of longitudinal studies, following several cohorts.

Low Income Home Energy Assistance Program (LIHEAP)
This federal program assists low-income households in meeting their costs for home energy. The funds may be used for the cost of running energy utilities, low cost weatherization (preparing the home for harsh weather), or other energy-related home repairs.


Managed investment account
A portfolio of stocks and bonds which is managed by a professional agent, usually for a fee based on the value of the assets in the account.

Manpower Development and Training Act (MDTA)
Legislation initially enacted in 1962 and amended in 1963, 1965, 1966, and 1968 to combat poverty by providing various employment assistance and employment training programs for the unemployed and the under-employed. It was subsequently replaced by CETA.

Margin loans through a stock broker
These are stock purchases where the purchaser borrows part of the purchase price from a bank or brokerage firm.  "Margin loan" refers to the amount borrowed for the purchase.  Technically, any time stock is used as collateral for a loan, even if it is already owned, it is called a margin loan.

Mature Women cohort
This group of 5,083 respondents born in April of 1922 through March of 1937 (ages 30-44 on March 31, 1967) was first interviewed in 1967 and was surveyed 21 times before its discontinuation in 2003.  The Mature Women cohort is one of the four NLS Original Cohorts.

A federal health program which pays for health costs of eligible low-income families.  Most families receiving welfare payments are eligible, as are certain institutionalized persons.

A federal health insurance program which pays for most hospital expenses.  Most persons age 65 and older are eligible for Medicare.  Persons under age 65 with major kidney failure and those receiving Social Security Disability payments are also eligible for Medicare.

Metropolitan Statistical Areas
Geographic areas defined by the Office of Management and Budget, based on the population levels and economic and social integration of surrounding areas.  These areas are generally county-based, with New England areas being defined by towns and cities. Definitions have been updated over the last three decades.  Early survey years included Standard Metropolitan Statistical Areas (SMSA). Metropolitan Statistical Areas (MSA), Consolidated Metropolitan Statistical Areas (CMSA) and Primary Metropolitan Statistical Areas (PMSA) were included in subsequent survey years. Core Based Statistical Areas (CBSA) have been included in the most recent survey years. Metropolitan Statistical Area boundaries may cross state lines.

Military Occupational Specialties (MOS)
An alphanumeric jobs/skills classification system for Army, Army Reserves, Army National Guard, Marine Corps, and Marine Reserves that describes the specific job a person is trained for or assigned to in those branches of the military.

Military Pay Grades
A pay level classification system for military personnel, used by all branches of the military, that is associated with ranks.  The ranks are enlisted (E), officer (O), and warrant officer (W).  There are nine enlisted grades, ten officer grades, and four warrant officer grades, with 1 being the lowest grade within each rank.  For example, an E-2 is the second lowest rank for enlisted personnel.

This is any loan that is collateralized by a home or other real estate.  The lender files a lien with the court system, which gives them the right to foreclose on (take over) the property should the borrower default on the loan.


National Longitudinal Survey of Youth 1979 (NLSY79)
This group of 12,686 male and female respondents was first interviewed in 1979 and has been interviewed a total of 24 times through 2010.  Respondents in this cohort were born in 1957 through 1964 (ages 14-21 as of December 31, 1978).

National Longitudinal Survey of Youth 1997 (NLSY97)
Respondents born in 1980-1984 (ages 12-16 as of December 31, 1996), were selected for inclusion in the newest NLS cohort.  The NLSY97 numbers 8,984 respondents.

Net Income
For farms and nonfarm businesses, the amount of income remaining after operating expenses are subtracted from the total or gross income.  For individuals who do not own a business, net income is generally the take-home pay, the amount of money earned after payroll withholdings.

Net Rental Income
Payments received from the rental of room(s), apartment(s), house(s), or any other real estate, after operating expenses are deducted.

NLS Investigator (or Investigator)
The data retrieval system for obtaining all public NLS data. In Investigator, cohort-specific datasets can be searched by Area of Interest, Word in Title, Question Text, Question Name, Reference Number, and Survey Year. A browse index is also available. After a successful variable search, users can save the variables to a tagset. NLS Investigator is accessed free of charge at

This type of organization is not maintained for the making of profit.

NORC at the University of Chicago
NORC, an independent research organization associated with the University of Chicago, conducts the NLS in partnership with the Center for Human Resource Research (CHRR) at The Ohio State University. NORC's roles include design, management, and fielding (conducting interviews). NORC was formerly known as the National Opinion Research Center.


Occupation Census code (NLSY97)
A 3-digit numeric code from the 1990 Occupational Classification System (in early rounds) and 2002 Classification System (in more recent rounds) used by the Census Bureau to assign codes to occupations (Census Bureau.  1990 Census of Population Alphabetical Index of Industries and Occupations.  Washington, DC:  U.S. Government Printing Office, 1991; more recent rounds).

Occupation Census code (NLSY79)
In early rounds, a 3-digit numeric code from the 1970 Occupational Classification System. 1980 codes were also assigned for current/most recent job only. Beginning with round 20 in 2002, the 2000 Classification System has been used to assign codes to occupations. Subsequent to 2002, the 2000 Classification System has incorporated several updates, including an expansion of the codes from 3-digit to 4-digit (Standard Occupational Classification Manual: 2000. U.S. Office of Management and Budget. Lanham, MD: Bernan Press; and Springfield, VA: National Technical Information Service).

Older Men cohort
This group of 5,020 respondents born in April of 1906 through March of 1921 (ages 45-59 on March 31, 1966) was first interviewed in 1966 and was subsequently surveyed 12 additional times before its discontinuation in 1990.  The Older Men cohort is one of the four NLS Original Cohorts.

Operating Expenses
Operating expenses for all nonfarm businesses are defined as the cost of utilities, annual depreciation of machinery and other business property, amount of net inventory decrease, wages and salaries paid to employees, cost of supplies and raw materials, business taxes, and interest on debts.  For farms, they are defined as the cost of feed, tools, livestock purchases, wages to farm workers, and depreciation of equipment or buildings.  They do not include capital expenditures such as purchase of land or machinery.

Original Cohorts
The four cohorts (Older Men, Mature Women, Young Men, and Young Women) selected in 1966 and first surveyed between 1966 and 1968. Data collection for these cohorts has been discontinued.

Out of the labor force (OLF)
See Labor Force and Employment Status.


Paper-and-pencil interview (PAPI)
Traditional paper-and-pencil interviews were used for NLS surveys until the mid-1990s. In 1993, the NLSY79 switched to computerized survey instruments (CAPI) and in 1995 the Women surveys followed suit. The NLSY97 main surveys were administered using computerized instruments from the start, although some traditional paper-and-pencil instruments were used for some NLSY97 screening interviews and for the administration of the NLSY97 Household Income Update.

Passive job search
A passive job search is one that utilizes only methods which could not result in a job offer without any further action on the part of the job seeker.  Methods include:

  • Looking at ads, but not responding
  • Attending job training programs (for example, how to write a resume, how to dress for an interview)
  • Other passive methods (for example, studying for a Real Estate license or picking up a job application)

See also Active job search.

Peabody Individual Achievement Test (PIAT)
The Peabody Individual Achievement Test, the math and reading assessments, were administered to the children of the NLSY79 mothers. For details, see Assessments in the Child/Young Adult Topical Guide. A later version of the PIAT-Revised Math Assessment also was given to a subset of the NLSY97 cohort.

Peabody Picture Vocabulary Test (PPVT).
This test is given to the children of the NLSY79 mothers. For details, see Assessments in the Child/Young adult Topical Guide.

Present value
The amount of money that sale of an asset would bring if it were sold at the time of the interview.

Primary Sampling Unit (PSU)
A primary sampling unit (PSU), as defined by NORC, is composed of either a single county (or the equivalent), a group of counties, or an SMSA and is based on population and area constraints. PSUs are the basic unit of sample selection for the NLSY97.

Primary Variables
Within the NLS Investigator, users have the option of selecting the variable preference level they wish to display, including primary variables, secondary variables, and tertiary variables. Primary variables are considered the most important and generally include all created and event-history variables, all roster variables, and respondents' responses to survey questions that are not superseded by better information in a roster or created variable.

Private employee
A private employee works for wages, salary, commission, tips, piece-rates, or pay in kind; this applies regardless of the occupation.  Respondents who work for settlement houses, churches, unions, and other private nonprofit organizations are also classified as private employees.

Profiles of American Youth
The name given to describe the ASVAB tests taken by NLSY79 respondent in the summer of 1980 and to NLSY97 respondents from summer 1997 to spring 1998.  The ASVAB, a military enlistment test, was administered to NLSY97 respondents and to other youths selected during the same screening process by the Department of Defense in an effort to establish new norms for the recruits entering the Armed Forces.

In NLS Investigator, the unique respondent public identification number that applies to all rounds of an NLS data set. When data are extracted, each respondent record is an observation. To merge multiple data sets from a NLS cohort, this is done using the PUBID. This variable is pre-selected in the NLS Investigator.

Public Assistance
Commonly referred to as "welfare," public assistance refers principally to Aid to Families with Dependent Children (AFDC or ADC).  Other programs include General Assistance (local titles include Outdoor Relief, Direct Relief, and General Relief) and Emergency Assistance.  Food stamps, clothing, free or reduced rent, public housing, or other nonmonetary assistance are not included.  With the Welfare Reform Act passed in August 1996, these types of programs were reconstituted as "Temporary Assistance to Needy Families" (TANF) and returned to state control, with some federal guidelines.

Public housing assistance
Includes rental certificates or vouchers provided by the government for low-income families.

Public Service Employment (PSE)
Authorized under Titles II and VI of CETA, PSE provides public service jobs, either through CETA or WIN, in areas where substantial or temporary service unemployment exists.  PSE placements are in government positions or in jobs with private, nonprofit service organizations.


Question name
A question name (or QNAME) is the code assigned to identify each survey question, which gives the location of the variable in the questionnaire or identifies it as a created variable. When possible, question names remain the same for the same question across survey years.


This is an abbreviation for "respondent."

An alphanumeric jobs/skills classification system for the Navy, Naval Reserves, Coast Guard, and Coast Guard Reserves that describes the specific job to which a person in those branches of the military is trained or assigned.

Reference number
A reference number (or RNUM) is a unique identifying number, originally beginning with "R," which is assigned to each variable in the data set.  Reference numbers never change after they are assigned to the variables from an interview even as additional information is added to the data set from later surveys.  Users should note that, because available "R" numbers have been exhausted, reference numbers can now begin with other letters of the alphabet.

Regular Job
A full-time or part-time civilian job with a definite arrangement to work for pay (or profit) for a specific number of hours or days a month.  It includes unpaid work on a family farm or for a family business.

Regular School
A school that provides credit toward an academic diploma or degree, such as an elementary school, junior high school, high school, college, or university, as contrasted with special schools that offer certificates rather than diplomas or degrees.  Schools or programs (such as technical schools, nursing programs, etc.) that provide credits that can be applied toward a regular academic diploma or degree are also considered regular school.  Courses taken to prepare for the GED are not included as regular school.

Rosenberg Self-Esteem Scale
A ten-item scale using four-point Likert forced-choice response to measure feelings of self-worth and competence taken from Rosenberg, M., Society and the Adolescent Self-Image.  Princeton, N.J.:  Princeton University Press, 1965.

Grids or lists that collect respondent information (known as roster variables) such as a list of children, employers, schools attended, etc. After the roster is created, it can be used to guide subsequent portions of the interview.

Rotter Scale or Internal-External Locus of Control Scale
A set of statements designed to measure the attitudes of respondents about the degree to which they have control over their own lives (Rotter 1966).

Income received from a percentage of gross sales from books, music, and so forth.

A codebook abbreviation for "Refusal." A variable is coded as such when a respondent refuses to answer that particular survey question.


Sampling weights
A numeric value calculated on the basis of each respondent's characteristics (gender, ethnicity, year of birth, sample type, and location).  The value, which is adjusted for differential probabilities of selection into the sample and for attrition, allows for population estimates. 

School Surveys (NLSY97)
Supplemental surveys of the high schools in the NLSY97 primary sampling units, conducted in 1996 and 2000-01. The school surveys collected information about school characteristics (enrollment, library size, vocational programs, ethnic diversity of students and teachers, etc.) and school-based learning programs.

School Survey (NLSY79)
A supplemental survey of the U.S. high schools attended by civilian NLSY79 respondents. The school survey collected information about the characteristics of the school (such as enrollment, library size, vocational programs, ethnic diversity of students and teachers), as well as individual respondent characteristics (such as participation in remedial courses, aptitude and ability test scores, date last enrolled).

School to Work Transition Program (SWTP)
Authorized under Title III of CETA, the School to Work Transition Program includes a number of pilot projects designed to prepare youth to move smoothly from an educational setting to the work force.  Specific goals of the program include helping dropouts obtain a GED while providing them with intensive vocational counseling and a job.

Screener, Household Roster, and Nonresident Roster Questionnaire (NLSY97)
The simple and extended screener sections were administered in round 1 to the initial sample of households to locate respondents eligible for the NLSY97.  NORC interviewers screened 75,291 households to identify eligible respondents based on age, race, and ethnicity.  If an eligible youth resided in the household, the remainder of the questionnaire (household roster and nonresident roster) was administered to collect basic demographic information about other household residents and key nonresident relatives.

Screener, Household Roster, and Nonresident Roster Questionnaire (NLSY79)
The short screening instrument was administered in 1978 to an initial sample of households to locate respondents eligible for the NLSY79. NORC interviewers screened approximately 75,000 dwellings and group quarters to identify eligible civilian respondents based on age, race, and ethnicity. Screening procedures were used to identify individuals eligible for both cross-sectional and supplemental samples. Eligible youth were contacted to participate in round 1 of the NLSY79 in 1979. Military supplemental sample members were sampled from rosters of persons on active duty as of September 30, 1978, with no formal screening interview.

Secondary Variables
Within the NLS Investigator, users have the option of selecting the variable preference level they wish to display, including primary variables, secondary variables, and tertiary variables. Secondary variables are superseded by created or roster variables. While these questions might be useful for very detailed research about a narrow topic, they won't be needed by most researchers.

Selected Reserves
Umbrella term used to refer to both the Reserves and the Guard branches of the military service.

SER-Jobs for Progress
SER (Service, Employment, and Redevelopment) is a private, nonprofit, community-based manpower organization, headquartered in Los Angeles, which seeks to provide education and skills training and employment placement for the economically disadvantaged, with primary emphasis on Hispanic or Latino Americans.

Social Security
Social Security benefits include disability, retirement, and survivors benefits, as well as Black Lung payments made to coal miners and payments made to retired railroad workers under the Railroad Retirement Act.

Special Pay Enlistment Bonus
A bonus paid to encourage enlistment for a 4-year term of service in designated skills of the Armed Forces.

Special Pay Selective Re-Enlistment Bonus
A bonus paid for re-enlistment in critical military specialties.

Summer Vacation
Respondents on summer vacation are considered enrolled.  In ambiguous cases, the respondent is considered to be enrolled if he or she intends to return to school (has not dropped out or formally left school).

Supplemental Security Income (SSI)
Supplemental Social Security is a form of public assistance paid to blind and disabled persons who are not covered under the Social Security program and to some people who are over age 65 whose income falls below a certain level. The program is administered through the Social Security Administration. This program should not be confused with state supplemental assistance or with regular Social Security benefits; checks are labeled "Supplemental Security Income Payment."

Survey year
Identifies survey waves, and is the year in which the survey period began for the particular interview round.

Suspension is a temporary prohibition of a student from access to school grounds.  It is used as a way of punishing the student for engaging in misconduct or breaking the school's rules. See also Expelled.


In NLS Investigator, the term means to select a variable by clicking on a checkbox.

A saved list of variables on NLS Investigator. NLS data users conduct variable searches and then choose a collection of specific variables to save either to the NLS server or to the user's PC for use at a later date.

Temporary Assistance for Needy Families (TANF)
Commonly referred to as welfare, this program helps families with dependent children by providing financial assistance each month.  States and territories operate the programs.  There is a time limit on the cash assistance, and work is a major component of TANF.  Work requirements under the program help recipients gain the experience need to find a job and become self-sufficient.

Tertiary Variables
Within the NLS Investigator, users have the option of selecting the variable preference level they wish to display, including primary variables, secondary variables, and tertiary variables. Tertiary variables are generally machine check items. These are included in the data to enable researchers to follow the flow of the interview, but in most cases they should not be used as input variables in research. These are only available when the "show all" Variable Preference Level is selected.

Payments given in addition to base wage or salary for a service performed or anticipated. See also Bonus and Commission.

Transcript survey (NLSY97)
At two separate points in time, survey staff collected high school transcripts from NLSY97 respondents' high schools after respondents were no longer enrolled as high school students and coded information from these transcripts for use by researchers. The NLSY97 transcript survey processed high school transcripts from 1,417 respondents in 1999-2000 (Wave 1) and from 4,815 respondents in 2004 (Wave 2) for a combined total of 6,232 respondents. 

Transcript Survey (NLSY79)
Sponsored by the National Center for Research in Vocational Education at The Ohio State University, the Transcript Survey for NLSY79 respondents was conducted during 1980–83.  Information collected includes courses, grades, credits, days absent, and rank in class.

Treasury notes, bills, or bonds
These long-term debt agents are issued by the U.S. government and can be owned directly or as part of a mutual fund.  Bills mature in less than a year; notes mature in 1-5 years; and bonds generally have a maturity period of more than 5 years.

A trust is an arrangement whereby the right to financial assets or property is held by one party, the "trustee" (or manager), for the benefit of another, the "beneficiary."  Trusts are often used as a way in which a parent or grandparent can distribute his or her assets to a child or grandchild at a particular point in that person's life.  Trusts require the drafting of legal documents by an attorney.


See Labor Force and Employment Status.

Unemployment Compensation (or Unemployment Insurance) benefits
Payments made by state or local governments to help replace wages lost by a worker who was laid off or fired from her/his job.  Benefits continue only for a set period of time and are taxable by the federal government.

A sample of respondents that received a particular survey question.

Upward Bound
This program is designed to prepare youth for successful postsecondary studies.

Urban League
A nonprofit community service organization that works to secure equal opportunities in all sectors of society for Black Americans and other minorities.  It uses the disciplines of social work, economics, law, and business management to achieve its goals.


Variable Preference Level
When a variable list is displayed in NLS Investigator, users will see a drop-down menu called "Variables Preference Level." In this drop-down menu, users can choose one of three levels of variables to be displayed: Primary, Primary + Secondary, or Show All (Primary, Secondary, and Tertiary). 

Variable title
A description of a particular variable.

Veteran Benefits
Benefits paid by the Veteran's Administration to former members of the Armed Forces for service- or nonservice-related disabilities.  It also includes educational benefits paid to veterans and any payments made to survivors of deceased veterans.

Veteran's Educational Assistance Program (VEAP)
Education assistance program for veterans whose active military service was contracted or began on or after January 1, 1977.  VEAP replaced the GI Bill.

Vocational or technical institute
This training program provides the trainee with vocational or technical skills and is not to be confused with technical classes in college.  This type of program does not contribute to a college degree.  Examples of vocational or technical institutes include beauty school, auto mechanics training, etc.

Vocational rehabilitation center
A facility offering specialized training to prepare disabled persons to enter or re-enter the work force.

Vocational Rehabilitation Programs
Federal/State programs authorized under the Vocational Rehabilitation Act of 1973 that provide a wide range of rehabilitation services for persons with physical and mental disabilities causing a substantial handicap to employment.  The programs focus on the individuals' abilities, interests, and needs in order to enable them to pursue gainful employment.


Women, Infants, and Children Supplemental Nutrition Program (WIC)
WIC is a federal assistance program designed to provide such supplemental dietary products as milk, butter, peanut butter, and orange juice to pregnant women, nursing mothers, infants, and children.

Work includes any activity for wages or salary; for profit or fees; or for payment "in kind" such as meals, living quarters, or supplies received in lieu of cash from someone other than a family member.  One hour or more of such activity constitutes work.  Work also includes unpaid activity of at least 15 hours a week on a family farm or business.  Respondents working as civilian employees of the Armed Forces or the National Guard are classified as working.

Worker's Compensation or Worker's Comp
Money paid to workers who have been hurt or injured on the job.  These benefits are not taxable. (Note:  Worker's Compensation includes payments from insurance companies only when the employer, not the employee, paid the premiums.)

Work-Study Programs
Government-sponsored programs designed to help eligible students finance their college education by providing part-time jobs, generally on campus.

Worker's Compensation or Worker's Comp
Payments made by private insurance companies, self-insured employers, or State funds financed under Federal and State worker's compensation laws to persons injured in work-related accidents.  It includes payments from insurance companies only when the premiums were paid by the employer, not the employee.


XRND (Cross Round)
If a variable has its year listed as cross-round (XRND), it means the information used to create this variable came from more than one interview round. In many cases, these variables aggregate information from the most recent interview round (CVC_RND) for each respondent. For example, the NLSY97 variable "CVC_HGC_EVER" is the highest grade ever reported through the last round of interview and has XRND listed as its survey year because the highest grade completed is present for each respondent, regardless of when the information was collected. In other cases, XRND variables aggregate information collected in several surveys, but not necessarily the most recent. For example, the age 40+ health module in the NLSY79 was asked of respondents in one interview between 1998 and 2006, depending on when they turned 40. Information from all five rounds has been combined into one set of variables for researcher convenience.


Young Adult cohort
This survey group is comprised of the children age 15 and older born to female NLSY79 respondents.  Prior to this age, the respondents were considered part of the Children of the NLSY79 cohort. Since 1994, a separate survey has been administered to children age 15 and up.

Young Men cohort
This group of 5,225 respondents born in April 1941 though March 1952 (ages 14-24 on March 31, 1966) was first interviewed in 1966 and was subsequently surveyed 11 additional times before its discontinuation in 1981.  The Young Men cohort is one of the four NLS Original Cohorts.

Young Women cohort
This group of 5,159 respondents born in 1943 though 1953 (ages 14-24 on December 31, 1967) was first interviewed in 1968 and was surveyed a total of 22 times through 2003, when it was discontinued.  The Young Women cohort is one of the four NLS Original Cohorts.