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PEDAR: Research Methodology Gender Differences in Participation and Completion of Undergraduate Education and How They Have Changed Over Time
Integrated Postsecondary Education Data System
The Current Population Survey
National Postsecondary Student Aid Study
High School and Beyond Longitudinal Study
National Educational Longitudinal Study
Beginning Postsecondary Students Longitudinal Study
1989-90 Beginning Postsecondary Students Longitudinal Study
1995-96 Beginning Postsecondary Students Longitudinal Study
Baccalaureate and Beyond Longitudinal Study
1993/97 Baccalaureate and Beyond Longitudinal Study
2000/01 Baccalaureate and Beyond Longitudinal Study
Accuracy of Estimates
Item Response Rates
Data Analysis System
Statistical Procedures
Differences Between Means
Executive Summary
Full Report (PDF)
Executive Summary (PDF)
 Accuracy of Estimates

The statistics in this report are estimates derived from a sample. Two broad categories of error occur in such estimates: sampling and nonsampling errors. Sampling errors occur because observations are made only on samples of students, not entire populations. Nonsampling errors occur not only in sample surveys but also in complete censuses of entire populations. Nonsampling errors can be attributed to a number of sources: inability to obtain complete information about all students in all institutions in the sample (some students or institutions refused to participate, or students participated but answered only certain items); ambiguous definitions; differences in interpreting questions; inability or unwillingness to give correct information; mistakes in recording or coding data; and other errors of collecting, processing, sampling, and imputing missing data.

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National Center for Education Statistics -
U.S. Department of Education