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Ability estimates for partial credit model

2 messages · Andrej Kastrin, Doran, Harold

#
Dear all,

I'm working on ability estimates using Rasch model. Using the "ltm" 
package, the procedure is quite simple:

## Factor Scores for the Rasch model
fit <- rasch(LSAT)
factor.scores(fit)

What about Partial Credit Model (PCM)? For PCM I use PCM function from 
eRm package. Is there any similar function like factor.scores to 
estimate ability scores using PCM model?

Best, Andrej
#
Yes, see the irt.ability function in the MiscPsycho package. This has
methods for maximum likelihood, and the two common bayesian estimates
(MAP, EAP). I am right now writing code for test characteristic methods.