Initialize.lmeStruct          package:nlme          R Documentation

Initialize an lmeStruct Object

Description:

     The individual linear mixed-effects model components of the
     'lmeStruct' list are initialized.

Usage:

     ## S3 method for class 'lmeStruct':
     Initialize(object, data, groups, conLin, control, ...)

Arguments:

  object: an object inheriting from class 'lmeStruct', representing a
          list of linear mixed-effects model components, such as
          'reStruct', 'corStruct', and 'varFunc' objects.

    data: a data frame in which to evaluate the variables defined in
          'formula(object)'.

  groups: a data frame with the grouping factors corresponding to the
          lme model associated with 'object' as columns, sorted from
          innermost to outermost grouping level.

  conLin: an optional condensed linear model object, consisting of a
          list with components '"Xy"', corresponding to a regression
          matrix ('X') combined with a response vector ('y'), and 
          '"logLik"', corresponding to the log-likelihood of the
          underlying lme model. Defaults to 'attr(object, "conLin")'.

 control: an optional list with control parameters for the
          initialization and optimization algorithms used in 'lme'.
          Defaults to 'list(niterEM=20, gradHess=TRUE)', implying that
          20 EM iterations are to be used in the derivation of initial
          estimates for the coefficients of the 'reStruct' component of
          'object' and, if possible, numerical gradient vectors and
          Hessian matrices for the log-likelihood function are to be
          used in the optimization algorithm.

     ...: some methods for this generic require additional arguments. 
          None are used in this method.

Value:

     an 'lmeStruct' object similar to 'object', but with initialized
     model components.

Author(s):

     Jose Pinheiro Jose.Pinheiro@pharma.novartis.com and Douglas Bates
     bates@stat.wisc.edu

See Also:

     'lme', 'Initialize.reStruct', 'Initialize.corStruct' ,
     'Initialize.varFunc'

