[R] Nominal Respose Model in R

[Dimitrios Rizopoulos]

AFAIK there exist functions to fit IRT models only for ordinal data.

In particular, look at function grm() that fits the Graded Response  
Model in the 'ltm' package (using Marginal Maximum Likelihood),  
function PCM() in the 'eRm' package (using Condtional Maximum  
Likelihood), and function MCMCordfactanal() in the 'MCMCpack' package  
(using a Bayesian approach).

I hope it helps.

Best,
Dimitris

----
Dimitris Rizopoulos
Ph.D. Student
Biostatistical Centre
School of Public Health
Catholic University of Leuven

Address: Kapucijnenvoer 35, Leuven, Belgium
Tel: +32/(0)16/336899
Fax: +32/(0)16/337015
Web: http://med.kuleuven.be/biostat/
      http://www.student.kuleuven.be/~m0390867/dimitris.htm


Quoting Xavier Giovanni Ordóñez Camacho <xavor at edu.ucm.es>:

> Hi:
>
> I have been working in Item Response Theory, exactly, with Nominal   
> Response Model (NRM). Exist in R
> a function for estimate parameter and ability from database for this Model?.
>
> Thank you,
>
>
> Xavier G. Ordóñez
>
>
>
> 	[[alternative HTML version deleted]]
>
>



Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm