NLSY97

Variables present in the NLSY97 main file are documented via (1) codebook; (2) accompanying supplemental documentation; and (3) error updates. This section describes these three components of the NLSY97 documentation and discusses the important types of information found within each.

 NLSY97 variables (as well as the variables from other other NLS cohorts) are accessed using NLS Investigator, which is available as a Web application. The main application of NLS Investigator is to access NLS variables for the purposes of identifying, selecting, extracting, and/or running frequencies or cross-tabulations. This interface allows the researcher to connect to a database and perform variable extractions without installing any software on a local computer.

After each round of the NLSY97, validation reinterviews are conducted with randomly selected respondents. Validation data for many of the rounds are available to public users and offer opportunities for studying response variance, item reliability, and other methodological issues.

The codebook provides information on item nonresponse, that is, which questions respondents declined to answer, answered as "don't know," or were skipped through. Also available in the database are timing variables that provide information on how long it took respondents to complete the total interview and to complete individual sections.

Several types of variables are present in the NLSY97 data, including:

The term "survey instrument" is used to refer to the NLSY97 questionnaires that serve as the primary source of information on a given respondent. In round 1, there were separate and distinctly different questionnaires for the household informant (the Screener, Household Roster, and Nonresident Roster Questionnaire), the NLSY97 respondent (the Youth Questionnaire), and the responding parent (the Parent Questionnaire).

The NLSY97 sampling weights, which are constructed in each survey year, provide the researcher with an estimate of how many individuals in the United States are represented by each NLSY97 respondent. Individual case weights are assigned to produce group population estimates when used in tabulations.

After the interviewer has finished surveying the respondent, the interviewer fills out an interviewer remarks section, providing objective and subjective details about the interview. Interviewers also provide demographic characteristics about themselves. In addition, information on the interviewer's contacts with the respondent (number of attempts at interviewing the respondent, for instance) is available.

The NLS program has established set procedures for ensuring respondent confidentiality and obtaining informed consent. These procedures comply with Federal law and the policies and guidelines of the U.S. Office of Management and Budget (OMB) and the U.S. Bureau of Labor Statistics:

This section provides information on Retention Rates in the NLSY97 and Reasons for Non-Interview.

Retention Rates in the NLSY97

The overall retention rate for round 20 is 74.7 percent. Table 1 shows the retention rates by sample type for rounds 2-20 of the NLSY97.