NAEP tdw - Proportion of Variance of the Group-Defining Contrasts Accounted for by the Principal Components Used in the Population-Structure Model, Grade 8 Mathematics Combined National and State 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 8 Mathematics Combined National and State 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 8 mathematics combined national and state 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 Mathematics Assessment.
All contrasts	1564	.90	.64	1.00	6	99	561	582	316
Student questionnaire	225	.89	.72	.99	0	46	38	89	52
Major reporting variables	125	.93	.75	1.00	0	3	28	43	51
Interactions between reporting variables	377	.90	.64	.98	6	18	100	196	57
Teacher questionnaire	277	.91	.73	.98	0	13	101	76	87
School questionnaire	523	.89	.75	.98	0	15	286	170	52
SD/ELL questionnaire	37	.91	.77	1.00	0	4	8	8	17

Last updated 21 May 2017 (DC)