IRT with TAM (and other packages)

When the Omega1 macro is used, it creates the two files mentioned earlier, Omega-IScores.csv and Omega-IScoresProg.R


It will always create those two files.  If there is an active internet connection, it may download some additional files.


As of December 2021, files that might be downloaded included these possibles: Omega-From-IScores.Rmd, Rasch-Analysis-TAM.Rmd, and IRTmoduleUWO-1.Rmd


The first of these files is mentioned towards the end of this paper, a paper which should be a general read even for those users whose interests regard the application of the TAM package.


Rasch-Analysis-TAM.Rmd computes Rasch statistics and creates ICCs, item characteristic curves having an empirical overlay, making it possible to visually judge goodness of fit.  It may be used by following the steps mentioned in the paper referenced in the paragraph immediately above -- where that paper references Omega-From-IScores.Rmd (page 11), substitute Rasch-Analysis-TAM.Rmd.


An example of the report produced by the Rasch-Analysis-TAM.Rmd script is shown here.


Other experimental work with related R packages is on-going; this includes, for example, a fairly comprehensive Rmd script for dichotomous IRT models based on work from the University of Western Ontario called "IRTModuleUWO-1.Rmd".  (This UWO paper is a good reference.)


Related tidbits:


Rmd files contain "R Markdown" code.  (Refer to the paper mentioned above.)


The "Omega-From-IScores.Rmd" file may be downloaded from here.


Rasch-Analysis-TAM.Rmd should be available here.


The IRTmodule "UWO-1.Rmd" file may be downloaded from here.