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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 Reading Combined National and State Assessment, by Type of Contrast: 2017
NAEP Technical DocumentationProportion of Variance of the Group-Defining Contrasts Accounted for by the Principal Components Used in the Population-Structure Model, Grade 8 Reading Combined National and State Assessment, by Type of Contrast: 2017
| Type of contrast | Number of contrasts | Mean | Minimum | Maximum | Number of contrasts by proportion of variance explained1 | ||||
|---|---|---|---|---|---|---|---|---|---|
| .00 - .70 | .70 - .80 | .80 - .90 | .90 - .95 | .95 - 1.00 | |||||
| All contrasts | 1741 | .90 | .62 | 1.00 | 14 | 96 | 658 | 599 | 374 |
| Student questionnaire | 440 | .92 | .72 | .99 | 0 | 13 | 103 | 185 | 139 |
| Major reporting variables | 303 | .89 | .74 | 1.00 | 0 | 22 | 135 | 88 | 58 |
| Interactions between reporting variables | 268 | .89 | .62 | .98 | 13 | 14 | 88 | 116 | 37 |
| Teacher questionnaire | 404 | .90 | .71 | .99 | 0 | 20 | 172 | 110 | 102 |
| School questionnaire | 295 | .88 | .73 | .98 | 0 | 19 | 154 | 94 | 28 |
| SD/EL questionnaire | 31 | .88 | .70 | .99 | 1 | 8 | 6 | 6 | 10 |
|
1 (Total Variance – Residual Variance) / Total Variance, where Total Variance consists of sampling, measurement, and other sources of error. NOTE: SD/EL = Students with disabilities/English learners. SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2017 Reading Assessment. | |||||||||
Last updated 11 May 2022 (SK)
