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NAEP Analysis and ScalingInitial ActivitiesClassical Item Analysis → Block-Level Descriptive Statistics as Defined After Scaling, Grade 4 Reading Combined National and State Assessment, by Block and School Type: 2017

NAEP Technical DocumentationBlock-Level Descriptive Statistics as Defined After Scaling, Grade 4 Reading Combined National and State Assessment, by Block and School Type: 2017

Block-level descriptive statistics as defined after scaling, grade 4 reading combined national and state assessment, by block and school type: 2017
StatisticType of school1Block R1Block R2Block R3Block R4Block R5Block R6Block R7Block R8Block R9Block R10
Number of scaled items11810101010101098
Unweighted sample sizePublic28,30028,700 28,000 28,100 28,100 28,200 28,600 28,200 28,000 28,000
Nonpublic600600600600600600600600600600
Weighted average item score2
Public.64.58.53.53.44.45.50.46.48.51
Nonpublic.71.66.58.60.52.53.58.54.53.58
Weighted average polyserialPublic.68.70.73.71.68.66.63.70.64.67
Nonpublic.69.69.72.67.67.65.63.67.64.65
Weighted alpha reliabilityPublic.77.71.79.77.76.75.72.78.70.63
Nonpublic.71.68.77.70.73.72.69.76.67.58
Weighted proportion of students attempting last item3
Public.90.87.86.89.87.84.85.84.86.93
Nonpublic.96.91.89.93.94.92.91.90.92.95
† Not applicable.
1 Nonpublic school sample includes only private schools, including Catholic schools. BIE and DoDEA schools are not included in either the public or nonpublic category.
2 The "Weighted average item score" of polytomous items is standardized to have a scale of 0 to 1 so they are comparable to dichotomously scored items.
3 The "Weighted proportion of students attempting last item" is equal to 1 – (Percent not responding to last item / 100).
NOTE: Item statistics in this table are described on the page Blocks of Items
SOURCE: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 2017 Reading Assessment.


Last updated 11 May 2022 (SK)