A dataset of item difficulty estimates and associated standard errors compiled from a curated subset of IRW datasets.
Used internally by irw_simu_diff() to generate empirically grounded item parameters for simulation.
Format
A data frame with N rows and 4 variables:
- dataset
Dataset identifier (character). Indicates the source dataset in IRW.
- item
Item identifier (character). A label for each item.
- difficulty
Estimated item difficulty (numeric).
- SE
Standard error of the difficulty estimate (numeric).
Source
Curated and compiled by the IRW package authors from selected datasets in the IRW repository.
Details
This pool includes binary-response items from IRW datasets that passed basic quality checks—
specifically, datasets with less than 50% missing data and without repeated or duplicate responses.
It is accessible to users and is used as the default source in irw_simu_diff().