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NAEP Analysis and ScalingInitial ActivitiesClassical Item Analysis → Block-Level Descriptive Statistics as Defined After Scaling, Grade 4 Mathematics Combined National and State Assessments, by Public and Nonpublic School Sessions: 2011
NAEP TECHNICAL DOCUMENTATIONBlock-level descriptive statistics as defined after scaling, grade 4 mathematics combined national and state assessments, by public and nonpublic school sessions: 2011
StatisticType of school1Block M3Block M4Block M5Block M6Block M7Block M8Block M9Block M10Block M11Block M12
† Not applicable.
Nonpublic school sample includes only private and Catholic schools.
NOTE: The "weighted average item score" of polytomous items are standardized to have a scale of 0 to 1 so they are comparable to dichotomously scored items. The "weighted proportion of students attempting last item" is equal to 1- (percent not responding to last item /100). 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), 2011 Mathematics Assessment.
Number of scaled items15151516151916151616
Unweighted sample sizePublic39,60039,60039,50040,40039,30039,80039,50039,50040,30040,100
Nonpublic1,2001,2001,2001,2001,2001,2001,2001,2001,2001,200
Weighted average item scorePublic.51.53.62.59.51.56.55.56.56.53
Nonpublic.54.57.65.64.55.60.57.59.59.58
Weighted average polyserialPublic.62.60.62.60.59.53.64.59.55.57
Nonpublic.62.61.64.60.57.52.62.57.52.55
Weighted alpha reliabilityPublic.76.74.77.77.76.77.78.70.71.73
Nonpublic.77.74.74.75.74.73.75.67.65.69
Weighted proportion of students attempting last item Public.95.90.90.93.88.67.96.96.93.89
Nonpublic.99.94.96.98.93.81.99.97.98.97

Last updated 05 October 2020 (DS)