Calculate the values of the statistics S_x2 from
Maria Orlando and David Thisen (2000).
Usage
orlando_itemf(patterns, G, zeta, model)
Arguments
patterns
list of patterns response (patterns$patterns), the frequency of each pattern (patterns$freq) and the latent traits (patterns$latent_traits).
G
number of quadrature points.
zeta
matrix of estimations of the parameters of the items (alphas, d's, guessing).
model
type of model ( "1PL", 2PL", "3PL" ).
Value
Orlando's statistic, degrees of freedom and p-value for each item.
References
Orlando, M. & Thissen, D. (2000). Likelihood-based item fit indices for dichotomous item
response theory models. Applied Psychological Measurement, 24, 50-64.