recalc.varFunc             package:nlme             R Documentation

Recalculate for varFunc Object

Description:

     This method function pre-multiples the '"Xy"' component of
     'conLin' by a diagonal matrix with diagonal elements given by the
     weights corresponding to the variance structure represented by
     'object'e and adds the log-likelihood contribution of 'object',
     given by 'logLik(object)', to the '"logLik"' component of
     'conLin'.

Usage:

     ## S3 method for class 'varFunc':
     recalc(object, conLin, ...)

Arguments:

  object: an object inheriting from class 'varFunc', representing a
          variance function structure.

  conLin: a 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 model.

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

Value:

     the recalculated condensed linear model object.

Note:

     This method function is only used inside model fitting functions,
     such as 'lme' and 'gls', that allow heteroscedastic error terms.

Author(s):

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

See Also:

     'varWeights', 'logLik.varFunc'

