parameters: NAEP IRT parameters.
In NAEPirtparams: IRT Parameters for the National Assessment of Education Progress

Description Usage Format References Examples

This data table contains NCES NAEP Assessment IRT parameters from 1990 to 2015. To find all item parameters for an assessment, filter the data table by level, subject, and year. Assessments from 1990 to 2000 also require filtering by assessmentCode and accommodations.

1	parameters

A data frame with columns

source: source of data, character
level: grade or age level of test, integer
levelType: "grade" or "age", character
NAEPid: test item ID, character
assessmentCode: "State" or "National", character
accommodations: "accom" or "no-accom", character
subtest: subtest within subject, character
subject: subject of test, character
year: year of test, integer
a: slope or a parameter, numeric
b: difficulty or d parameter, numeric
c: guessing or g parameter, numeric
d1: location of cut point 1 for polytomous item, numeric
d2: location of cut point 2 for polytomous item, numeric
d3: location of cut point 3 for polytomous item, numeric
d4: location of cut point 4 for polytomous item, numeric
d5: location of cut point 5 for polytomous item, numeric

Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress (NAEP), 1990-2015, various subjects. Retrieved from https://nces.ed.gov/nationsreportcard/tdw/analysis/scaling_irt.aspx

## Not run: 

param <- NAEPirtparams::parameters
param8M2005 <- param[param$level == 8 & param$subject == 'Mathematics' & param$year == 2005, ]
head(param8M2005)
      source level levelType  NAEPid  ...  subtest     subject year    a     b    c  ...  
7657 website     8     grade M066201  ...  algebra Mathematics 2005 0.77 -1.75 0.07  ...  
7658 website     8     grade M067401  ...  algebra Mathematics 2005 0.92  1.28 0.18  ...  
7659 website     8     grade M086101  ...  algebra Mathematics 2005 0.63  0.32 0.11  ...  
7660 website     8     grade M047701  ...  algebra Mathematics 2005 1.01  1.29 0.26  ...  
7661 website     8     grade M067301  ...  algebra Mathematics 2005 1.02 -0.03 0.16  ...  
7662 website     8     grade M067701  ...  algebra Mathematics 2005 0.78 -2.01 0.06  ...  


## End(Not run)