CDM (version 4.8-0)

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 class 'din':
anova(object,\dots)

## S3 method for class 'gdina':
anova(object,\dots)

## S3 method for class 'mcdina':
anova(object,\dots)

## S3 method for class 'gdm':
anova(object,\dots)

## S3 method for class 'slca':
anova(object,\dots)

Arguments

object

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

...

Further arguments to be passed

See Also

din, gdina, gdm, mcdina, slca

Examples

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

# Model 1
d1 <- din(sim.dina, q.matr = sim.qmatrix )
# Model 2 with equal guessing and slipping parameters
d2 <- 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

#############################################################################
# EXAMPLE 2: anova with gdina objects
#############################################################################

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

# Model 4: DINA model
d4 <- 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