Plotting in conquestr
In conquestr: An R Package to Extend 'ACER ConQuest'

knitr::opts_chunk$set(
  collapse = TRUE,
  comment = "#>"
)

Introduction

conquestr has two main types of plots. The first is plots based on the plot command in ACER ConQuest. These plots are done using the generic function conquestr::plotRout The second is more general plots, usually of the inputs or outputs of IRT estimate.

Example

plotRout

library(conquestr)
myRout <- ConQuestRout()
plotRout(myRout)

General Plots

You can plot an arbitrary information function against a distribution of students - a so called information Wright map.

myDeltaDots <- data.frame(
  id = c(1:10),
  itemid = paste0("item", 1:10),
  delta = rnorm(10)
)

MyTaus <- data.frame(
  id = c(2L, 10L),
  itemId = NA,
  step = c(1L, 1L),
  tau = rnorm(2)
)

myItemList <- makeItemList(deltaDot = myDeltaDots, tau = MyTaus)

myPersons <- rnorm(500, 1, 1)
informationWrightMap(myItems = myItemList, myAbilities = myPersons, minTheta = -6, maxTheta = 6)