R Snippets for IRT

MORE FLEXIBILITY USING THE PERSON AND ITEM SIDE FUNCTIONS INTRODUCTION Version 1.2 of the WrightMap package allows you to directly access the functions used for drawing the person and item side...

https://www.wrightmap.org/2020/04/25/173151.html

USING CONQUEST OUTPUT AND MAKING THRESHOLDS Updated Fri 24-Apr-2020 INTRO In this part of the tutorial, we’ll show how to load ConQuest output to make a CQmodel object and then WrightMaps. ...

https://www.wrightmap.org/2020/04/25/wrightmap-tutorial.html

PLOTTING MULTIDIMENSIONAL & POLYTOMOUS MODELS Updated Fri 24-Apr-2020 MULTIDIMENSIONAL MODELS We will need again to load RColorBrewer for this example. install.packages("RColorBrewer") libr...

https://www.wrightmap.org/2020/04/24/230721.html

PLOTTING THE ITEMS IN DIFFERENT WAYS Updated Fri 24-Apr-2020 SETUP We start by creating mock person and item estimates. For the person proficiencies we create a single vector with 1000 valu...

https://www.wrightmap.org/2020/04/24/wrightmap-tutorial.html

PLOTTING UNIDIMENSIONAL/DICHOTOMOUS MODELS Updated Fri 24-Apr-2020 SETUP AND BASICS This is an introduction to the wrightMap function in the WrightMap package. The wrightMap function creates ...

https://www.wrightmap.org/2020/04/24/wrightmap-tutorial-plotting.html