CDM (version 8.2-6)

anova: Likelihood Ratio Test for Model Comparisons

Description

This function compares two models estimated with din, gdina or gdm using a likelihood ratio test.

Usage

# S3 method for din
anova(object,...)
# S3 method for gdina
anova(object,...)
# S3 method for gdm
anova(object,...)
# S3 method for mcdina
anova(object,...)
# S3 method for reglca
anova(object,...)
# S3 method for slca
anova(object,...)

Arguments

object

Two objects of class din, gdina, mcdina, slca, gdm, reglca

...

Further arguments to be passed

See Also

din, gdina, gdm, mcdina, slca

Examples

#############################################################################
# EXAMPLE 1: anova with din objects
#############################################################################

# Model 1
d1 <- CDM::din(sim.dina, q.matr=sim.qmatrix )
# Model 2 with equal guessing and slipping parameters
d2 <- CDM::din(sim.dina, q.matr=sim.qmatrix, guess.equal=TRUE, slip.equal=TRUE)
# model comparison
anova(d1,d2)
  ##     Model   loglike Deviance Npars      AIC      BIC    Chisq df  p
  ##   2    d2 -2176.482 4352.963     9 4370.963 4406.886 268.2071 16  0
  ##   1    d1 -2042.378 4084.756    25 4134.756 4234.543       NA NA NA

if (FALSE) {
#############################################################################
# EXAMPLE 2: anova with gdina objects
#############################################################################

# Model 3: GDINA model
d3 <- CDM::gdina( sim.dina, q.matr=sim.qmatrix )

# Model 4: DINA model
d4 <- CDM::gdina( sim.dina, q.matr=sim.qmatrix, rule="DINA")

# model comparison
anova(d3,d4)
  ##     Model   loglike Deviance Npars      AIC      BIC    Chisq df       p
  ##   2    d4 -2042.293 4084.586    25 4134.586 4234.373 31.31995 16 0.01224
  ##   1    d3 -2026.633 4053.267    41 4135.266 4298.917       NA NA      NA
}