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NAEP Sample Design → NAEP 2002 Sample Design → 2002 State Assessment Sample Design

2002 State Assessment Sample Design


Target Population

Sampling Frame

New-School Sampling Frame

Stratification of Schools in Public School Sampling Frame

School Sample Selection

Trial Urban District Assessment School Selection

Substitute Schools

Ineligible Schools

Student Sampling

School Participation

Student Participation

The NAEP 2002 state assessment program included assessments of fourth- and eighth-grade students in public schools for both subjects. A representative sample of public school students was drawn in each participating jurisdiction. Each sample was designed to produce aggregate estimates as well as estimates for various student groups of interest with approximately equal precision for all the participating jurisdictions. The target sample in each jurisdiction participating in the operational studies was 6,300 students per grade (see School Sample Selection). With a general target of 60 sampled students per school, approximately 100 schools per participating jurisdiction in each grade were needed.

There were a number of jurisdictions in the United States that declined participation in the state-level operational assessments. These jurisdictions included Alaska, Bureau of Indian Affairs schools, Colorado, New Hampshire, New Jersey, and South Dakota, and Iowa for grade 8 only (i.e., Iowa participated for fourth grade).

The target population for the 2002 state assessment included students in public schools who were enrolled in the fourth and eighth grades at the time of assessment. The sampling frame included public schools having the relevant grade in each jurisdiction. The samples were selected based on a two-stage sample design: selection of schools within participating jurisdictions, and selection of students within schools. The first-stage samples of schools were selected with probability proportional to a measure of size based on the estimated grade enrollment in the schools. Special procedures were used for jurisdictions with many small schools, and for jurisdictions having small numbers of grade-eligible schools.

As part of the selection process, schools were hierarchically stratified by district status (districts with over 20 percent of its state’s students were in a separate stratum), urbanization, and minority class. Within minority strata, schools were sorted by state achievement data for jurisdictions where it was available, and by median household income of the ZIP Code area where the school was located for jurisdictions where state achievement data were not available. Achievement data were supplied by the jurisdictions themselves. Median income data (1989) were obtained from the 1990 Census. Other stratification variables were obtained from the National Center for Education Statistics’ Common Core of Data.

From the stratified frame of public schools within each jurisdiction, for each grade, a systematic random sample of about 100 grade-eligible schools was drawn, with probability proportional to a measure of size based on the estimated grade-specific enrollment of the school. One or more sessions were sampled within each school. The number of sessions selected depended on the school’s estimated grade enrollment, though the majority of schools at grade 4 were allocated a single session.

Five large urban districts participated in the Trial Urban District Assessment (TUDA) program. Additional schools were sampled from these five districts.

Each selected school provided a list of eligible enrolled students, from which a systematic sample of students was drawn. Sixty students, if possible, were selected from each school (30 students for reading and 30 for writing).

Last updated 04 December 2008 (RF)

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