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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 Variance Accounted for By Principal Components Used in NAEP Population-Structure Models → Proportion of Variance of the Group-Defining Contrasts Accounted for by the Principal Components Used in the Population-Structure Model, Grade 8 Mathematics Combined National and State Main Assessment: 2007
| Type of contrast | Number of contrasts | Mean | Minimum | Maximum | Number of contrasts by proportion1 of variance explained | ||||
|---|---|---|---|---|---|---|---|---|---|
| 0.00 - 0.70 | 0.70 - 0.80 | 0.80 - 0.90 | 0.90 - 0.95 | 0.95 - 1.00 | |||||
| 1 (Total Variance – Residual Variance)/Total Variance, where Total Variance consists of both sampling and measurement error variance. NOTE: NIES = National Indian Education Study; SD/ELL = Students with disabilities/English language learners. SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2007 Mathematics Assessment. |
|||||||||
| All contrasts | 1633 | 0.90 | 0.58 | 1.00 | 21 | 123 | 528 | 521 | 440 |
| Student questionnaire | 195 | 0.90 | 0.58 | 0.99 | 3 | 21 | 48 | 74 | 49 |
| Major reporting variables | 117 | 0.93 | 0.70 | 1.00 | 0 | 3 | 22 | 39 | 53 |
| Interactions between reporting variables | 556 | 0.91 | 0.61 | 0.99 | 12 | 22 | 132 | 184 | 206 |
| Teacher questionnaire | 194 | 0.90 | 0.69 | 0.98 | 1 | 17 | 69 | 64 | 43 |
| School questionnaire | 271 | 0.89 | 0.73 | 0.98 | 0 | 20 | 120 | 103 | 28 |
| NIES questionnaire | 257 | 0.87 | 0.67 | 0.99 | 5 | 36 | 127 | 50 | 39 |
| SD/ELL questionnaire | 43 | 0.92 | 0.74 | 0.99 | 0 | 4 | 10 | 7 | 22 |
Last updated 24 June 2010 (GF)
