getGroups.lmList {nlme} | R Documentation |
The grouping factor determining the partitioning of the observations
used to produce the lm
components of object
is
extracted.
## S3 method for class 'lmList' getGroups(object, form, level, data, sep)
object |
an object inheriting from class |
form |
an optional formula with a conditioning expression on its
right hand side (i.e. an expression involving the |
level |
a positive integer vector with the level(s) of grouping to be used when multiple nested levels of grouping are present. This argument is optional for most methods of this generic function and defaults to all levels of nesting. Not used. |
data |
a data frame in which to interpret the variables named in
|
sep |
character, the separator to use between group levels when
multiple levels are collapsed. The default is |
a vector with the grouping factor corresponding to the lm
components of object
.
Jose Pinheiro and Douglas Bates bates@stat.wisc.edu
fm1 <- lmList(distance ~ age | Subject, Orthodont) getGroups(fm1)