lmerTest: anova.lmerModLmerTest – R documentation

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anova.lmerModLmerTest

ANOVA Tables for Linear Mixed Models

Description

ANOVA table with F-tests and p-values using Satterthwaite's or Kenward-Roger's method for denominator degrees-of-freedom and F-statistic. Models should be fitted with lmer from the lmerTest-package.

Usage

## S3 method for class 'lmerModLmerTest'
anova(
  object,
  ...,
  type = c("III", "II", "I", "3", "2", "1"),
  ddf = c("Satterthwaite", "Kenward-Roger", "lme4")
)

Arguments

`object`	an `lmerModLmerTest` object; the result of `lmer()` after loading the lmerTest-package.
`...`	potentially additional `lmer` or `lm` model objects for comparison of models in which case `type` and `ddf` arguments are ignored.
`type`	the type of ANOVA table requested (using SAS terminology) with Type I being the familiar sequential ANOVA table.
`ddf`	the method for computing the denominator degrees of freedom and F-statistics. `ddf="Satterthwaite"` (default) uses Satterthwaite's method; `ddf="Kenward-Roger"` uses Kenward-Roger's method, `ddf = "lme4"` returns the lme4-anova table, i.e., using the anova method for `lmerMod` objects as defined in the lme4-package and ignores the `type` argument. Partial matching is allowed.

Details

The "Kenward-Roger" method calls pbkrtest::KRmodcomp internally and reports scaled F-statistics and associated denominator degrees-of-freedom.

Value

an ANOVA table

Author(s)

Rune Haubo B. Christensen and Alexandra Kuznetsova

Examples

data("sleepstudy", package="lme4")
m <- lmer(Reaction ~ Days + (Days | Subject), sleepstudy)
anova(m) # with p-values from F-tests using Satterthwaite's denominator df
anova(m, ddf="lme4") # no p-values

# Use the Kenward-Roger method
if(requireNamespace("pbkrtest", quietly = TRUE))
  anova(m, ddf="Kenward-Roger")

lmerTest

Tests in Linear Mixed Effects Models

v3.1-3

GPL (>= 2)

Authors

Alexandra Kuznetsova [aut], Per Bruun Brockhoff [aut, ths], Rune Haubo Bojesen Christensen [aut, cre], Sofie Pødenphant Jensen [ctb]

Initial release