Proportion of Variance of the Group-Defining Contrasts Accounted for by the Principal Components Used in the Population-Structure Model, Grade 8 Civics National Assessment: 2014

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 Civics National Assessment: 2014

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Proportion of Variance of the Group-Defining Contrasts Accounted for by the Principal Components Used in the Population-Structure Model, Grade 8 Civics National Assessment: 2014
Proportion of variance of the group-defining contrasts accounted for by the principal components used in the population-structure model, grade 8 civics national assessment: 2014
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/EL = Students with disabilities/English learners. In 2014, grades 4 and 12 were not assessed. SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2014 Civics Assessment.
All contrasts	1236	.90	.67	.99	6	57	484	503	186
Student questionnaire	230	.88	.69	.98	1	33	82	81	33
Major reporting variables	72	.91	.80	.99	0	2	29	22	19
Interactions between reporting variables	247	.89	.67	.98	5	21	76	113	32
Teacher questionnaire	372	.90	.84	.99	0	0	197	117	58
School questionnaire	278	.92	.86	.99	0	0	78	157	43
SD/EL questionnaire	34	.88	.79	.95	0	1	22	10	1
Student questionnaire indices	3	.94	.93	.95	0	0	0	3	0

Last updated 30 August 2021 (ML)