The estimated coefficients at level i are obtained by adding
together the fixed effects estimates and the corresponding random
effects estimates at grouping levels less or equal to i. The
resulting estimates are returned as a data frame, with rows
corresponding to groups and columns to coefficients. Optionally, the
returned data frame may be augmented with covariates summarized over
groups.
an object inheriting from class
lme, representing
a fitted linear mixed-effects model.
OPTIONAL ARGUMENTS:
augFrame
an optional logical value. If
TRUE, the returned
data frame is augmented with variables defined in
data; else,
if
FALSE, only the coefficients are returned. Defaults to
FALSE.
level
an optional positive integer giving the level of grouping
to be used in extracting the coefficients from an object with
multiple nested grouping levels. Defaults to the highest or innermost
level of grouping.
data
an optional data frame with the variables to be used for
augmenting the returned data frame when `augFrame =
TRUE. Defaults to the data frame used to fit
object.
which
an optional positive integer vector specifying which
columns of
data should be used in the augmentation of the
returned data frame. Defaults to all columns in
data.
FUN
an optional summary function or a list of summary functions
to be applied to group-varying variables, when collapsing
data
by groups. Group-invariant variables are always summarized by the
unique value that they assume within that group. If
FUN is a
single function it will be applied to each non-invariant variable by
group to produce the summary for that variable. If
FUN is a
list of functions, the names in the list should designate classes of
variables in the frame such as
ordered,
factor, or
numeric. The indicated function will be applied to any
group-varying variables of that class. The default functions to be
used are
mean for numeric factors, and
Mode for both
factor and
ordered. The
Mode function, defined
internally in
gsummary, returns the modal or most popular
value of the variable. It is different from the
mode function
that returns the S-language mode of the variable.
omitGroupingFactor
an optional logical value. When
TRUE
the grouping factor itself will be omitted from the group-wise
summary of
data but the levels of the grouping factor will
continue to be used as the row names for the returned data frame.
Defaults to
FALSE.
VALUE:
a data frame inheriting from class
coef.lme with the estimated
coefficients at level
level and, optionally, other covariates
summarized over groups. The returned object also inherits from classes
ranef.lme
and
data.frame.
SEE ALSO:
,
,
,
,
EXAMPLES:
fm1 <- lme(distance ~ age, Orthodont, random = ~ age | Subject)
coef(fm1)
coef(fm1, augFrame = TRUE)