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 4 Civics National Assessment: 2010
| 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. SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2010 Civics Assessment. |
|||||||||
| All contrasts | 1304 | 0.90 | 0.68 | 0.99 | 3 | 35 | 630 | 381 | 255 |
| Student questionnaire | 157 | 0.89 | 0.69 | 0.99 | 1 | 13 | 68 | 55 | 20 |
| Major reporting variables | 66 | 0.92 | 0.72 | 0.99 | 0 | 1 | 29 | 13 | 23 |
| Interactions between reporting variables | 393 | 0.91 | 0.68 | 0.99 | 2 | 21 | 113 | 124 | 133 |
| Teacher questionnaire | 396 | 0.89 | 0.80 | 0.99 | 0 | 0 | 250 | 96 | 50 |
| School questionnaire | 254 | 0.90 | 0.85 | 0.99 | 0 | 0 | 147 | 82 | 25 |
| SD/ELL questionnaire | 38 | 0.89 | 0.80 | 0.98 | 0 | 0 | 23 | 11 | 4 |
Last updated 05 January 2016 (GF)