NAEP tdw - Proportion of Scale Score Variance Accounted for by the Conditioning Models, Meaning Vocabulary National Assessment, By Grade: 2013

NAEP Technical DocumentationProportion of scale score variance accounted for by the conditioning models, meaning vocabulary national assessment, by grade: 2013
Grade	Number of initial conditioning contrasts¹	Number of principal components¹	Proportion² of scale score variance
¹¹ Excluding the constant term and including forced-in variables. ²² (Total Variance – Residual Variance)/Total Variance, where Total Variance consists of sampling, measurement, and other sources of error. NOTE: Single overall scale SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2013 Reading Assessment.
4	106	28	.35
8	111	32	.36
12	111	27	.31

Last updated 21 May 2017 (DC)