lrt.asreml {asreml} | R Documentation

## REML Likelihood ratio tests

### Description

Extracts the REML log likelhood and numbers of variance parameters from a sequence of `asreml` objects, and computes a sequence of pairwise likelihood ratio tests.

### Usage

    ## S3 method for class 'asreml'
    lrt(..., boundary = TRUE)

### Arguments

`...` | A sequence of asreml objects assumed nested when arranged in increasing order of number of parameters.
`boundary` | If `TRUE` (the default) hypothesized parameter values being tested lie on the boundary of the parameter space.

### Details

The models are arranged in increasing order of number of variance parameters and assumed nested in this sequence. If the reduced model is obtained by setting positively-constrained variance parameters in the full model to zero, set `boundary` to `TRUE`. In this case the probability is computed using a mixture of chi-square distributions as described in Self and Liang (1987).

### Value

A data frame with a row for each successive pairwise test, and columns for the likelihood ratio statistic, degrees of freedom and number of parameters.

### References

Self SC, Liang KY (1987). “Asymptotic Properties of Maximum Likelihood Estimators and Likelihood Ratio Tests Under Non-standard Conditions.” Journal of the American Statistical Association, 82, 605–610.

[Package asreml version 4.1.0.176 Index]