dLR: Dimensionality test for the multidimensional polytomous Rasch...

Description Usage Arguments Details Value Author(s) References See Also Examples

Description

This function tests whether the multidimensional polytomous Rasch model can be reduced to a unidimensional polytomous model.

Usage

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dLRT(MPRMobj)

## S3 method for class 'dLR'
print(x, ...)

## S3 method for class 'dLR'
summary(object, ...)

Arguments

MPRMobj

Object of class MPRM

x

object of class dLR

...

...

object

object of class dLR

Details

For this test, a unidimensional model assuming the categories as linearly dependent is computed. Subsequently a Likelihood Ratio test is conducted.

Value

emp_Chi2

χ^2 distributed value of the Likelihood Ratio test

df

degrees of freedom of the test statistic

pval

p value of the test statistic

Author(s)

Christine Hohensinn

References

Fischer, G. H. (1974). Einfuehrung in die Theorie psychologischer Tests [Introduction to test theory]. Bern: Huber.

See Also

MPRM LRT

Examples

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#simulate data set
simdat <- simMPRM(rbind(matrix(c(-1.5,0.5,0.5,1,0.8,-0.3, 0.2,-1.2), 
   ncol=4),0), 500)

#estimate MPRM item parameters
res_mprm <- MPRM(simdat$datmat)

res_dlrt <- dLRT(res_mprm)
summary(res_dlrt)

pcIRT documentation built on May 1, 2019, 11:09 p.m.