Methods defined for objects returned from the ANOVA functions aov_car
et al. of class afex_aov
containing both the ANOVA fitted via car::Anova
and base R's aov
.
# S3 method for afex_aov
anova(object, es = afex_options("es_aov"),
observed = NULL, correction = afex_options("correction_aov"),
MSE = TRUE, intercept = FALSE, p_adjust_method = NULL,
sig_symbols = attr(object$anova_table, "sig_symbols"), ...)# S3 method for afex_aov
print(x, ...)
# S3 method for afex_aov
summary(object, ...)
recover_data.afex_aov(object, ..., model = afex_options("emmeans_model"))
emm_basis.afex_aov(object, trms, xlev, grid, ...,
model = afex_options("emmeans_model"))
object of class afex_aov
as returned from aov_car
and related functions.
Effect Size to be reported. The default is given by
afex_options("es_aov")
, which is initially set to "ges"
(i.e., reporting generalized eta-squared, see details). Also supported is
partial eta-squared ("pes"
) or "none"
.
character vector referring to the observed (i.e., non
manipulated) variables/effects in the design. Important for calculation of
generalized eta-squared (ignored if es
is not "ges"
), see
details.
Character. Which sphericity correction of the degrees of
freedom should be reported for the within-subject factors. The default is
given by afex_options("correction_aov")
, which is initially set to
"GG"
corresponding to the Greenhouse-Geisser correction. Possible
values are "GG"
, "HF"
(i.e., Hyunh-Feldt correction), and
"none"
(i.e., no correction).
logical. Should the column containing the Mean Sqaured Error (MSE)
be displayed? Default is TRUE
.
logical. Should intercept (if present) be included in the
ANOVA table? Default is FALSE
which hides the intercept.
character
indicating if p-values for individual effects should be adjusted for multiple comparisons (see p.adjust and details).
Character. What should be the symbols designating
significance? When entering an vector with length(sig.symbol) < 4
only those elements of the default (c(" +", " *", " **", " ***")
)
will be replaced. sig_symbols = ""
will display the stars but not
the +
, sig_symbols = rep("", 4)
will display no symbols. The
default is given by afex_options("sig_symbols")
.
further arguments passed through, see description of return value for details.
argument for emmeans()
and rlated functions that allows to choose on which model the follow-up tests for ANOVAs with repeated-measures factors are based. "univariate"
uses the aov
model and "multivariate"
uses the lm
model. Default given by afex_options("emmeans_mode")
. Multivariate tests likely provide a better correction for violations of sphericity.
same as for emm_basis
.
anova
Returns an ANOVA table of class c("anova", "data.frame")
. Information such as effect size (es
) or df-correction are calculated each time this method is called.
summary
For ANOVAs containing within-subject factors it returns the full output of the within-subject tests: the uncorrected results, results containing Greenhousse-Geisser and Hyunh-Feldt correction, and the results of the Mauchly test of sphericity (all achieved via summary.Anova.mlm
). For other ANOVAs, the anova
table is simply returned.
print
Prints (and invisibly returns) the ANOVA table as constructed from nice
(i.e., as strings rounded nicely). Arguments in ...
are passed to nice
allowing to pass arguments such as es
and correction
.
recover_data
and emm_basis
Provide the backbone for using emmeans
and related functions from emmeans directly on afex_aov
objects by returning a emmGrid-class
object. Should not be called directly but through the functionality provided by emmeans.
Exploratory ANOVA, for which no detailed hypotheses have been specified a priori, harbor a multiple comparison problem (Cramer et al., 2015). To avoid an inflation of familywise Type I error rate, results need to be corrected for multiple comparisons using p_adjust_method
.
p_adjust_method
defaults to the method specified in the call to aov_car
in anova_table
. If no method was specified and p_adjust_method = NULL
p-values are not adjusted.
Cramer, A. O. J., van Ravenzwaaij, D., Matzke, D., Steingroever, H., Wetzels, R., Grasman, R. P. P. P., ... Wagenmakers, E.-J. (2015). Hidden multiplicity in exploratory multiway ANOVA: Prevalence and remedies. Psychonomic Bulletin & Review, 1-8. doi:10.3758/s13423-015-0913-5