Table of Contents  |  Search Technical Documentation  |  References

NAEP Analysis and Scaling → Scale Linking and Transformation to the Reporting Metric → Comparisons of Distributions of Linking Samples for NAEP Assessments → Comparison Means and Percentiles of 1998 Scores and 2002 Transformed Provisional Scores in Reading at Grade 8, by Scale: 2002

The 2002 equating estimates were based on the 2002 equating sample, which were placed on the reporting metric through transformation identified by linking the 2000 provisional estimates to the original estimates.The 2002 operational transformed provisional estimates were obtained through a process of scaling and transformation described below. First, the scaling results for the 2002 operational sample were used to obtain the provisional estimates. Second, through common population linking of the results for the equating sample and the corresponding national part of the operational sample, transformation constants were identified and applied to the operational sample results, resulting in the operational transformed provisional estimates shown in the table. If the transformation was done correctly, the equating and operational transformed provisional estimates should have the same mean within each scale.

NAEP Technical DocumentationComparison means and percentiles of 1998 scores and 2002 transformed provisional scores in reading at grade 8, by scale: 2002

Scale	Statistic	1998 scores	2002 transformed provisional scores	Difference between the 2002 provisional scores and the 1998 scores
Composite	Mean	264.34	264.34	#
	10th percentile	218.85	220.20	1.35
	25th percentile	242.13	243.55	1.42
	50th percentile	266.51	266.87	0.36
	75th percentile	288.46	287.70	-0.76
	90th percentile	307.01	305.10	-1.91
Reading for literary experience	Mean	264.54	264.54	#
	10th percentile	218.73	219.37	0.64
	25th percentile	241.55	242.43	0.88
	50th percentile	265.98	266.49	0.51
	75th percentile	288.71	288.62	-0.09
	90th percentile	308.42	307.46	-0.96
Reading to gain information	Mean	264.61	264.61	#
	10th percentile	217.87	217.86	-0.01
	25th percentile	241.88	242.75	0.87
	50th percentile	266.48	267.17	0.69
	75th percentile	289.57	289.21	-0.36
	90th percentile	308.97	308.15	-0.82
Reading to perform a task	Mean	263.40	263.40	#
	10th percentile	208.99	209.78	0.79
	25th percentile	237.15	238.59	1.44
	50th percentile	266.28	266.61	0.33
	75th percentile	292.39	291.65	-0.74
	90th percentile	314.11	313.16	-0.95
# Rounds to zero. SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2002 Reading Assessment.

Printer-friendly Version