NAEP tdw - Proportion of Variance of the Group-Defining Contrasts Accounted for by the Principal Components Used in the Population-Structure Model, Grade 12 Reading National Assessment: 2013

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 Reading National Assessment: 2013

NAEP Technical DocumentationProportion of variance of the group-defining contrasts accounted for by the principal components used in the population-structure model, grade 12 reading national assessment: 2013
Type of contrast	Number of contrasts	Mean	Minimum	Maximum	Number of contrasts by proportion¹ of variance explained
Type of contrast	Number of contrasts	Mean	Minimum	Maximum	.00 - .70	.70 - .80	.80 - .90	.90 - .95	.95 - 1.00
¹(Total Variance – Residual Variance)/Total Variance, where Total Variance consists of sampling, measurement, and other sources of error. 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), 2013 Reading Assessment.
All contrasts	1256	.90	.69	.99	1	55	555	435	210
Student questionnaire	224	.89	.70	.98	0	28	87	76	33
Major reporting variables	85	.92	.75	.99	0	1	26	26	32
Interactions between reporting variables	313	.90	.69	.98	1	24	90	154	44
School questionnaire	602	.90	.83	.99	0	0	344	170	88
SD/ELL questionnaire	32	.91	.78	.99	0	2	8	9	13

Last updated 21 May 2017 (DC)