- 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 Geography 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 Geography Assessment. |
|||||||||
| All contrasts | 1053 | 0.90 | 0.66 | 1.00 | 10 | 53 | 415 | 343 | 232 |
| Student questionnaire | 238 | 0.89 | 0.67 | 0.99 | 4 | 20 | 98 | 84 | 32 |
| Major reporting variables | 62 | 0.90 | 0.73 | 1.00 | 0 | 3 | 29 | 10 | 20 |
| Interactions between reporting variables | 430 | 0.91 | 0.66 | 0.99 | 6 | 28 | 101 | 152 | 143 |
| School questionnaire | 290 | 0.90 | 0.81 | 0.99 | 0 | 0 | 174 | 82 | 34 |
| SD/ELL questionnaire | 33 | 0.89 | 0.78 | 0.96 | 0 | 2 | 13 | 15 | 3 |
Last updated 13 June 2016 (GF)
