Estimate or extract residual or model-based degrees of freedom
from regression models.
Usage
get_df(x, ...)
# S3 method for default
get_df(x, type = "residual", verbose = TRUE, ...)
Arguments
x
A statistical model.
...
Currently not used.
type
Can be "residual", "model" or "analytical". "residual"
tries to extract residual degrees of freedoms. If residual degrees of freedom
could not be extracted, returns analytical degrees of freedom, i.e. n-k
(number of observations minus number of parameters). "model" returns
model-based degrees of freedom, i.e. the number of (estimated) parameters.
# NOT RUN {model <- lm(Sepal.Length ~ Petal.Length * Species, data = iris)
get_df(model) # same as df.residual(model)get_df(model, type = "model") # same as attr(logLik(model), "df")# }