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NLS Documentation
  • Where to find everything you need to know
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General Documentation
  • NLS Website: www.bls.gov/nls
  • NLS News: Newsletter points out topics of interest, announces data releases, reports significant errors, and lists recent research.
  • NLS Bibliography: Searchable database of all NLS research known to our staff, available online at www.nlsbibliography.org.
  • NLS Investigator: Documentation items are also available through the “documentation” section of the NLS Investigator.
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NLS Website
  • The NLS website at www.bls.gov/nls offers an overview of the survey program and links to various other resources. Features include:
    • General description of each cohort
    • NLS-related press releases
    • Frequently asked questions
    • Links to documentation items
    • Link to online NLS Investigator
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NLS Website
  • The NLS Website includes a link to the order/download page.
    • Complete list of NLS data and documentation.
    • Access items electronically or in hard copy.
    • If the item name is a hyperlink, you can also click on the link to view the item online without downloading.
  • When you place an order or make a download, you will be asked to provide some personal information.
    • We keep this information confidential and don't send you unsolicited emails.
    • We occasionally may need to send out a very important notice about a problem with data for one of the NLS cohorts. In this case we send emails to everyone who downloaded the data so that you will know as quickly as possible if the problem will affect your research.

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NLS News
  • The quarterly newsletter points out topics of interest, announces data releases, reports significant errors, and lists recent NLS research.
  • View PDF versions of current and past newsletters on the NLS Website (under "Publications and Other Documentation")
      • NLS News web page

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NLS Bibliography
  • The annotated bibliography is a searchable database of all NLS research known to our staff. Users can search for research by author, title, source, format, topic keywords, or any word in the citation.
    • Available online at www.nlsbibliography.org.
    • Includes form to submit new citations or correct citations in the bibliography.
    • Provides helpful hints for citing NLS data in research.
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NLS Investigator
  • Another online resource is the “documentation” section of NLS Investigator. The Investigator includes links to the online items and also to an Investigator user manual.
      • Investigator Documentation

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Cohort-Specific Documentation
  • Questionnaires: Show the questions asked of respondents
  • Codebooks: Show the data collected in the interviews
  • User's Guides: Overview survey procedures, sample selection, response rates. Topical sections summarize survey content, describe differences across rounds, give other data notes.
  • Codebook Supplements: Provide detailed technical information on specific variables
  • Geocode Codebook Supplements: Provide detailed information for use with the restricted-use geocode CD
  • Errata: Describe any errors that might be discovered subsequent to data release
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Questionnaires
  • In brief, the goal of the questionnaire is to show the questions asked of the respondents, along with the "skip patterns," so that users know what questions were asked and who answered them. Because the NLS program has been in existence for nearly 4 decades, the format of the questionnaires has changed over time.
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Questionnaires: PAPI years
  • PAPI means Paper-and-Pencil Interview.
  • The early surveys were done entirely with paper and pencil--interviewers had a supply of hard copy questionnaires and filled one out for each respondent. Users can look at the exact paper instrument used by interviewers.
  • We scanned the PAPI instruments and made the resulting images available as PDF files. These can be viewed online or downloaded at the NLS order/download page. (Because they are PDF files with images, these files are quite large.)
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Sample PAPI questionnaire
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Questionnaires: PAPI years
  • PAPI instruments are available for the following cohorts/survey years:
    • Older Men, all surveys (1966-1990)
    • Young Men, all surveys  (1966-1981)
    • Mature Women, 1967-1992
    • Young Women, 1968-1993
    • NLSY79, 1979-1992 plus 1978 household screener
    • NLSY79 child, 1986-1998, plus portions of 2000 administration
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Questionnaires: PAPI years
  • Note that we refer to a single "instrument" for each survey year. However, the "instrument" may actually include several different forms, particularly in the NLSY79 and NLSY79 child interviews. For example, a complete set of instruments for a PAPI-year NLSY79 interview might include the main questionnaire, a Household Record form, an Employer Supplement, a confidential drug use supplement, and a confidential abortion card. When you order or download an instrument for a given year, you will receive all of the pieces used in that year.
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Questionnaires: CAPI years
  • CAPI means Computer-Assisted Personal Interview.
  • NLS interviews are now conducted using laptops. The computer determines which questions to ask based on internal calculations and "skip patterns" not seen by the interviewer or respondent.
  • CAPI questionnaires are more complicated than their PAPI counterparts, because computerization permits more complex skip patterns.
  • To represent this computer-driven interview for researchers, the survey program produces a series of “question records,” which show both the actual questions and the skip pattern instructions that guide the instrument.
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Questionnaires: CAPI years
  • For recent rounds, we have created a hyperlinked version of the questionnaire. Researchers can use the hyperlinks to follow question paths forward or backward through the questionnaire.
  • CAPI questionnaires can be downloaded from the NLS order/download page or can be reached by following the documentation hyperlinks in NLS Investigator.
      • Sample CAPI questionnaire section
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Questionnaires: CAPI years
  • CAPI instruments are available for the following cohorts/survey years:
    • Mature and Young Women, 1995-2003 (beginning in 1995 the two women's cohorts
      were interviewed using the same instrument and field procedures)
    • NLSY79, 1993-present
    • NLSY79 child, 2000-present
    • NLSY79 Young Adult, all surveys (1994-present)
    • NLSY97, all surveys (1997-present)
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Questionnaires: CAPI years
  • Although the term CAPI implies an in-person interview, some respondents are interviewed by telephone in each round. If some aspect of survey procedure differs between in-person and telephone interviews, this will be specified in the user's guide.  Respondents who were interviewed by telephone can be identified by using interview mode variables in the data set.
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Codebooks
  • Questionnaires show what will be asked during the interview; codebooks show the data that was actually collected during the interview and variables that were created later.
  • The codebook is not actually a book or even a set of printouts. Instead, it is a series of computer records, one for each variable in the data set.
  • Codebook pages can be accessed through NLS Investigator.
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Codebooks: List of Variables
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Codebooks: Single Codebook Page
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User's Guides
  • Each data release is accompanied by a detailed cohort-specific user's guide.
  • Technical chapters describe survey procedures, sample selection, response rates, changes to the sample over time, weighting and design effects.
  • Topical chapters summarize survey questions on a given topic, describe changes across rounds, explain which respondents are eligible to answer the questions, describe any created variables related to the topic, and provide special "user notes" with important information about various aspects of the data.
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User's Guides
  • The user’s guides are posted online in HTML.
  • You can browse the entire user’s guide from the BLS website, the NLS order/download page, or the NLS Investigator documentation section.
  • The guides are also linked to the codebook pages for individual variables. We are as thorough and accurate as possible in creating these links, but there may be instances when additional information is available on a topic that does not appear as a link on the codebook page. If you are familiar with the content of the entire guide, you can check in other sections if the initial link does not provide the information you are looking for.
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User’s Guides: Asterisk Tables
  • If you are looking for a quick overview of the questions asked in various rounds, check the “asterisk tables” in the back of each user’s guide.
      • NLSY79 asterisk table
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Codebook Supplements
  • Data releases are accompanied by cohort-specific codebook supplements.
  • These documents, organized in attachments and appendices, contain very detailed technical information about specific NLS variables.
    • Example 1: Industry and Occupation codes
    • Example 2: Programming code for created variables
  • For the NLSY79 and NLSY97, special Geocode Codebook Supplements are also produced. Similar to the main file supplements, these provide coding and other technical information for geographic variables.
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Codebook Supplements
  • For earlier rounds, the codebook supplement was printed in hard copy. Printed codebook supplements can be ordered on the NLS order/download page and can also be viewed in PDF or HTML format from that page.
  • For the last several rounds, the codebook supplement information has also been converted to HTML format and hyperlinked to the codebook pages for individual variables.
  • Beginning with the round 20 (2002) survey of the NLSY79 and the round 6 (2003-2004) survey of the NLSY97, the codebook supplements are available only in HTML.
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Errata
  • Survey staff exercise great care when processing interview data and creating variables. However, in any large data set errors will inevitably be found.
  • Errata pages are maintained for each data set. Links to the errata pages can be found on both the NLS Website (follow the cohort-specific links) and on the NLS order/download page. Users are strongly urged to check these pages regularly to become aware of any issues that might affect their research. For very serious problems, survey staff may attempt to contact known data users via email or, as a last resort, via U.S. mail (this is why we collect contact information).
      • Sample errata page
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For Additional Help
  • If you don't find the answer to your question in our documentation, you can contact NLS User Services for assistance.
    • NLS User Services Office
      921 Chatham Lane, Suite 100
      Columbus, Ohio 43221
      usersvc@postoffice.chrr.ohio-state.edu
      phone 614.442.7366, fax 614.442.7329