Extract parameter variance covariance matrix

Usage

# S4 method for class 'SingleGroupClass'
vcov(object)

Arguments

object: an object of class SingleGroupClass, MultipleGroupClass, or MixedClass

References

Chalmers, R., P. (2012). mirt: A Multidimensional Item Response Theory Package for the R Environment. Journal of Statistical Software, 48(6), 1-29. doi:10.18637/jss.v048.i06

Examples


if (FALSE) { # \dontrun{
x <- mirt(Science, 1, SE=TRUE)
vcov(x)

} # }