R/data.R

In mstDIF: A Collection of DIF Tests for Multistage Tests

#' A Toy Example of 1000 Respondents Working on a Multistage Test
#'
#' Data of 1000 respondents working on a multistage test using a (1,2,2) design. The responses were generated
#' based on the 2PL model. Each module consists of 7 items. Data were generated using the mstR package, version 1.2
#' (https://cran.r-project.org/web/packages/mstR/index.html).  
#'
#' @format A list with 7 elements:
#' \describe{
#'   \item{resp}{The response matrix, with rows corresponding to respondents and columns corresponding to items.}
#'   \item{it}{A matrix of item parameters. The columns contain the discrimination, difficulty, pseudo-guessing and 
#'   inattention parameters of the 4PL model. The discrimination parameters were drawn from a N(1,0.2) distribution.
#'   The difficulty parameters were drawn from normal distributions. For module 1 (items 1-7), this distributions was N(0,1),
#'   for modules 2 and 4 (items 8-14 and 22-28) it was N(1,1) and for modules 3 and 5 (items 15-21 and 29-35)
#'   the distribution was N(-1,1).}
#'   \item{theta}{The true ability parameters.}
#'   \item{theta_est}{The ability parameters estimated by the WLE estimator.}
#'   \item{group_categ}{A simulated categorical person covariate. The first 500 respondents belong to group 0, the remaining 500
#'   respondents to group 1.}
#'   \item{group_cont}{A simulated continuous person covariate. It simulates an age covariate, with a uniform distribution between
#'   20 and 60.}
#'   \item{see_est}{The standard errors of the estimated ability parameters.}
#' }
"toydata"