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NAEP Analysis and ScalingScale Linking and Transformation to the Reporting MetricComparisons of Distributions of Linking Samples for NAEP Assessments → Comparison of Means and Percentiles of 2013 Scores and 2013-Transformed Provisional Scores, Grade 8 Reading Combined National and State Assessment, by Scale: 2015

NAEP Technical DocumentationComparison of Means and Percentiles of 2013 Scores and 2013-Transformed Provisional Scores, Grade 8 Reading Combined National and State Assessment, by Scale: 2015

Original estimates are based on previous assessment data and previous assessment scaling results, transformed to the reporting metric using the transformation identified during the analysis of the previous assessment data. Provisional estimates are based on previous assessment data and current assessment scaling results. These are on the theta metric specified by the scaling program. The original and provisional estimates for the linking sample are used to find the transformation constants necessary to place the current assessment scale scores on the scale used to report previous assessment scale scores. The transformed provisional estimates are based on previous assessment data and current assessment scaling results, transformed to the reporting metric using the transformation constants calculated from the original and provisional estimates for the linking sample. If the transformation constants are correct, the original and transformed provisional means should be the same.

Comparison of means and percentiles of 2013 scores and 2013-transformed provisional scores, grade 8 reading combined national and state assessment, by scale: 2015
ScaleStatistic
Original 2013 estimate 2013-transformed provisional estimateDifference between the provisional estimate and the original estimate
Composite scaleMean267.60267.60#
10th percentile223.12222.29-0.82
25th percentile246.32245.65-0.67
50th percentile269.46269.30-0.16
75th percentile291.17291.610.44
90th percentile309.82310.770.96
LiteraryMean265.15265.15#
10th percentile217.70217.27-0.43
25th percentile242.37242.02-0.35
50th percentile267.06267.02-0.04
75th percentile290.28290.440.16
90th percentile310.39310.700.32
InformationMean269.60269.60#
10th percentile224.88224.79-0.08
25th percentile248.14247.64-0.50
50th percentile271.37271.12-0.25
75th percentile293.30293.420.12
90th percentile312.09312.600.51
# Rounds to zero.
SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2015 Reading Assessment.

Last updated 18 November 2021 (ML)