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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 Assessments: 2011
| 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), 2011 Mathematics Assessment. |
|||||||||
| All contrasts | 2093 | 0.90 | 0.66 | 1.00 | 9 | 87 | 878 | 720 | 399 |
| Student questionnaire | 63 | 0.90 | 0.69 | 0.99 | 1 | 7 | 15 | 17 | 23 |
| Major reporting variables | 294 | 0.92 | 0.73 | 1.00 | 0 | 17 | 74 | 119 | 84 |
| Interactions between reporting variables | 371 | 0.90 | 0.66 | 0.98 | 6 | 20 | 102 | 180 | 63 |
| Teacher questionnaire | 315 | 0.91 | 0.76 | 0.98 | 0 | 8 | 120 | 89 | 98 |
| School questionnaire | 701 | 0.90 | 0.77 | 0.99 | 0 | 6 | 377 | 238 | 80 |
| NIES questionnaire | 311 | 0.88 | 0.67 | 0.99 | 2 | 25 | 181 | 68 | 35 |
| SD/ELL questionnaire | 38 | 0.92 | 0.78 | 0.99 | 0 | 4 | 9 | 9 | 16 |
Last updated 05 January 2016 (GF)
