Probabilistic Guttman Model
prob.guttman.RdThis function estimates the probabilistic Guttman model which is a special case of an ordered latent trait model (Hanson, 2000; Proctor, 1970).
Usage
prob.guttman(dat, pid=NULL, guess.equal=FALSE, slip.equal=FALSE,
itemlevel=NULL, conv1=0.001, glob.conv=0.001, mmliter=500)
# S3 method for prob.guttman
summary(object,...)
# S3 method for prob.guttman
anova(object,...)
# S3 method for prob.guttman
logLik(object,...)
# S3 method for prob.guttman
IRT.irfprob(object,...)
# S3 method for prob.guttman
IRT.likelihood(object,...)
# S3 method for prob.guttman
IRT.posterior(object,...)Arguments
- dat
An \(N \times I\) data frame of dichotomous item responses
- pid
Optional vector of person identifiers
- guess.equal
Should the same guessing parameters for all the items estimated?
- slip.equal
Should the same slipping parameters for all the items estimated?
- itemlevel
A vector of item levels of the Guttman scale for each item. If there are \(K\) different item levels, then the Guttman scale possesses \(K\) ordered trait values.
- conv1
Convergence criterion for item parameters
- glob.conv
Global convergence criterion for the deviance
- mmliter
Maximum number of iterations
- object
Object of class
prob.guttman- ...
Further arguments to be passed
Value
An object of class prob.guttman
- person
Estimated person parameters
- item
Estimated item parameters
- theta.k
Ability levels
- trait
Estimated trait distribution
- ic
Information criteria
- deviance
Deviance
- iter
Number of iterations
- itemdesign
Specified allocation of items to trait levels