data.pars1.rasch: Item Parameters for Three Studies Obtained by 1PL and 2PL...

data.pars1.raschR Documentation

Item Parameters for Three Studies Obtained by 1PL and 2PL Estimation

Description

The datasets contain item parameters to be prepared for linking using the function linking.haberman.

Usage

data(data.pars1.rasch)
data(data.pars1.2pl)

Format

  • The format of data.pars1.rasch is:

    'data.frame': 22 obs. of 4 variables:
    $ study: chr "study1" "study1" "study1" "study1" ...
    $ item : Factor w/ 12 levels "M133","M176",..: 1 2 3 4 5 1 6 7 3 8 ...
    $ a : num 1 1 1 1 1 1 1 1 1 1 ...
    $ b : num -1.5862 0.40762 1.78031 2.00382 0.00862 ...

    Item slopes a are fixed to 1 in 1PL estimation. Item difficulties are denoted by b.

  • The format of data.pars1.2pl is:

    'data.frame': 22 obs. of 4 variables:
    $ study: chr "study1" "study1" "study1" "study1" ...
    $ item : Factor w/ 12 levels "M133","M176",..: 1 2 3 4 5 1 6 7 3 8 ...
    $ a : num 1.238 0.957 1.83 1.927 2.298 ...
    $ b : num -1.16607 0.35844 1.06571 1.17159 0.00792 ...


alexanderrobitzsch/sirt documentation built on March 18, 2024, 1:29 p.m.