R/PIMap.R

In changxiulee/BayesianRasch: Bayesian Rasch Modeling

#' PIMap
#'
#' Plot a person-item / Wright map
#'
#'
#' @param obj An BPCM model or BRSM model
#' @param g If BPCM / BRSM has DIF, specify group of interest
#' @export PIMap

PIMap = function(obj, g = 1){
  if(obj$DIF == TRUE) {
    show("This is not available for DIF object")
  }else{
    codaSamples = obj$mcmc
    data = obj$data
    item = obj$item

    theta.v = theta(obj, g)[,3]
    data = data[, item]
    if(min(apply(data, 2, min,na.rm = TRUE)) == 0){data = data + 1}
    K = apply(data, 2, max,na.rm = TRUE)
    beta.v  = beta(obj, g)[,3]
    WrightMap::wrightMap(theta.v, sort(beta.v))
  }
}