Table of Contents | Search Technical Documentation | References
NAEP Analysis and Scaling → Estimation of Population and Student Group Distributions → Examining the Population-Structure Models Used in NAEP → Proportion of Scale Score Variance Accounted for by the Population-Structure Models → Proportion of Scale Score Variance Accounted for by the Population-Structure Model, Vocabulary National Assessment, by Grade: 2015
NAEP Technical Documentation Proportion of Scale Score Variance Accounted for by the Population-Structure Model, Vocabulary National Assessment, by Grade: 2015
| Grade | Number of initial conditioning contrasts2 | Number of principal components2 | Proportion of scale score variance1 |
|---|---|---|---|
| Scale | |||
| 4 | 2834 | 788 | .61 |
| 8 | 2555 | 650 | .63 |
| 12 | 2417 | 470 | .62 |
|
1 (Total Variance – Residual Variance) / Total Variance, where Total Variance consists of sampling, measurement, and other sources of error. 2 Excluding the constant term. NOTE: Single overall scale. SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2015 Reading Assessment. | |||
Last updated 30 November 2021 (ML)