\HeaderA{Initialize.reStruct}{Initialize reStruct Object}{Initialize.reStruct}
\keyword{models}{Initialize.reStruct}
\begin{Description}\relax
Initial estimates for the parameters in the \code{pdMat} objects
forming \code{object}, which have not yet been initialized, are
obtained using the methodology described in Bates and Pinheiro
(1998). These estimates may be refined using a series of EM
iterations, as described in Bates and Pinheiro (1998). The number of
EM iterations to be used is defined in \code{control}.
\end{Description}
\begin{Usage}
\begin{verbatim}
## S3 method for class 'reStruct':
Initialize(object, data, conLin, control, ...)
\end{verbatim}
\end{Usage}
\begin{Arguments}
\begin{ldescription}
\item[\code{object}] an object inheriting from class \code{reStruct},
representing a random effects structure and consisting of a list of
\code{pdMat} objects.
\item[\code{data}] a data frame in which to evaluate the variables defined in
\code{formula(object)}.
\item[\code{conLin}] a condensed linear model object, consisting of a list
with components \code{"Xy"}, corresponding to a regression matrix
(\code{X}) combined with a response vector (\code{y}), and
\code{"logLik"}, corresponding to the log-likelihood of the
underlying model.
\item[\code{control}] an optional list with a single component \code{niterEM}
controlling the number of iterations for the EM algorithm used to
refine initial parameter estimates. It is given as a list for
compatibility with other \code{Initialize} methods. Defaults to
\code{list(niterEM = 20)}.
\item[\code{...}] some methods for this generic require additional
arguments.  None are used in this method.
\end{ldescription}
\end{Arguments}
\begin{Value}
an \code{reStruct} object similar to \code{object}, but with all
\code{pdMat} components initialized.
\end{Value}
\begin{Author}\relax
Jose Pinheiro \email{Jose.Pinheiro@pharma.novartis.com} and Douglas Bates \email{bates@stat.wisc.edu}
\end{Author}
\begin{References}\relax
Bates, D.M. and Pinheiro, J.C. (1998) "Computational methods for
multilevel models" available in PostScript or PDF formats at
http://franz.stat.wisc.edu/pub/NLME/
\end{References}
\begin{SeeAlso}\relax
\code{\LinkA{reStruct}{reStruct}}, \code{\LinkA{pdMat}{pdMat}},
\code{\LinkA{Initialize}{Initialize}}
\end{SeeAlso}

