Initialize.varFunc {nlme} | R Documentation |
Initialize varFunc Object
Description
This method initializes object
by evaluating its associated
covariate(s) and grouping factor, if any is present, in data
;
determining if the covariate(s) need to be updated when the
values of the coefficients associated with object
change;
initializing the log-likelihood and the weights associated with
object
; and assigning initial values for the coefficients in
object
, if none were present. The covariate(s) will only be
initialized if no update is needed when coef(object)
changes.
Usage
## S3 method for class 'varFunc'
Initialize(object, data, ...)
Arguments
object |
an object inheriting from class |
data |
a data frame in which to evaluate the variables named in
|
... |
this argument is included to make this method compatible with the generic. |
Value
an initialized object with the same class as object
representing a variance function structure.
Author(s)
José Pinheiro and Douglas Bates bates@stat.wisc.edu
See Also
Examples
vf1 <- varPower( form = ~ age | Sex )
vf1 <- Initialize( vf1, Orthodont )