itemplot

itemplot,bfactorClass-method

itemplot,mirtClass-method

itemplot-method

a computed model of class
  <code>bfactorClass</code> or <code>mirtClass</code>

object

a single numeric value indicating which item
  to plot

item

plot type to use, information
  (<code>'info'</code>), information contours
  <code>('infocontour')</code>, or item trace lines
  (<code>'trace'</code>)

type

additional arguments to be passed to lattice

<code>itemplot</code> displays various item based IRT plots.

plot

Analysis of dichotomous and polytomous response data using
        latent trait models under the Item Response Theory paradigm.
        Includes univariate and multivariate one-, two-, three-, and
        four-parameter logistic models, graded response models,
        generalized partial credit models, nominal models, multiple
        choice models, and multivariate partially-compensatory models.
        These can be used in an exploratory or confirmatory manner with
        optional user defined linear constraints. Exploratory models
        can be estimated via quadrature or stochastic methods, a
        generalized confirmatory bi-factor analysis is included, and
        confirmatory models can be fit with a Metropolis-Hastings
        Robbins-Monro algorithm which can include polynomial or product
        constructed latent traits.

itemplot: Displays item surface and information plots

Description

Arguments

See Also

Examples