- Surveys & Programs
- Data & Tools
- Fast Facts
- News & Events
- Publications & Products
- About Us
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 12 Science National Main Assessment: 2009
| Type of contrast | Number of contrasts | Mean | Minimum | Maximum | Number of contrasts by proportion1 of variance explained | ||||
|---|---|---|---|---|---|---|---|---|---|
| 0.00 - 0.70 | 0.71 - 0.80 | 0.81 - 0.90 | 0.91 - 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: 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), 2009 Science Assessment. |
|||||||||
| All contrasts | 1,577 | 0.90 | 0.65 | 0.99 | 11 | 69 | 688 | 487 | 322 |
| Student questionnaire | 309 | 0.88 | 0.65 | 0.99 | 6 | 34 | 125 | 96 | 48 |
| Major reporting variables | 62 | 0.91 | 0.74 | 0.99 | 0 | 2 | 30 | 9 | 21 |
| Interaction between reporting variables | 493 | 0.92 | 0.65 | 0.99 | 5 | 30 | 99 | 170 | 189 |
| School questionnaire | 676 | 0.89 | 0.83 | 0.99 | 0 | 0 | 419 | 200 | 57 |
| SD/ELL questionnaire | 37 | 0.89 | 0.77 | 0.98 | 0 | 3 | 15 | 12 | 7 |
Last updated 05 January 2016 (GF)
