\HeaderA{plot.ranef.lmList}{Plot a ranef.lmList Object}{plot.ranef.lmList}
\keyword{models}{plot.ranef.lmList}
\begin{Description}\relax
If \code{form} is missing, or is given as a one-sided formula, a
Trellis dot-plot of the random effects is generated, with a different
panel for each random effect (coefficient). Rows in the dot-plot are
determined by the \code{form} argument (if not missing) or by the row
names of the random effects (coefficients). If a single factor is
specified in \code{form}, its levels determine the dot-plot rows
(with possibly multiple dots per row); otherwise, if \code{form}
specifies a crossing of factors, the dot-plot rows are determined by
all combinations of the levels of the individual factors in the 
formula. The Trellis function \code{dotplot} is used in this method
function.

If \code{form} is a two-sided formula, a Trellis display is generated,
with a different panel for each variable listed in the right hand side
of \code{form}. Scatter plots are generated for numeric variables and
boxplots are generated for categorical (\code{factor} or
\code{ordered}) variables.
\end{Description}
\begin{Usage}
\begin{verbatim}
## S3 method for class 'ranef.lmList':
plot(x, form, grid, control, ...)
\end{verbatim}
\end{Usage}
\begin{Arguments}
\begin{ldescription}
\item[\code{x}] an object inheriting from class
\code{ranef.lmList}, representing the estimated coefficients or
estimated random effects for the \code{lmList} object from which it was
produced.

\item[\code{form}] an optional formula specifying the desired type of plot. If
given as a one-sided formula, a \code{dotplot} of the estimated
random effects (coefficients) grouped according to all combinations of
the levels of the factors named in \code{form} is returned. Single
factors (\code{\textasciitilde{}g}) or crossed factors (\code{\textasciitilde{}g1*g2}) are
allowed. If given as a two-sided formula, the left hand side must
be a single random effects (coefficient) and the right hand side
is formed by covariates in \code{x} separated by \code{+}. A
Trellis display of the random effect (coefficient) versus the named
covariates is returned in this case. Default is \code{NULL}, in
which case  the row names of the random effects (coefficients) are
used.
\item[\code{grid}] an optional logical value indicating whether a grid should
be added to plot. Only applies to plots associated with two-sided
formulas in \code{form}. Default is \code{FALSE}.
\item[\code{control}] an optional list with control values for the
plot, when \code{form} is given as a two-sided formula. The control
values are referenced by name in the \code{control} list and  only
the ones to be modified from the default need to be
specified. Available values include: \code{drawLine}, a logical
value indicating whether a \code{loess} smoother should be added to
the scatter plots and a line connecting the medians should be added
to the boxplots (default is \code{TRUE}); \code{span.loess}, used
as the \code{span} argument in the call to \code{panel.loess}
(default is \code{2/3}); \code{degree.loess}, used as the
\code{degree} argument in the call to \code{panel.loess} (default
is \code{1}); \code{cex.axis}, the character expansion factor for
the x-axis (default is \code{0.8}); \code{srt.axis}, the rotation
factor for the x-axis (default is \code{0}); and \code{mgp.axis}, the
margin parameters for the x-axis (default is \code{c(2, 0.5, 0)}).
\item[\code{...}] optional arguments passed to the Trellis \code{dotplot}
function.

\end{ldescription}
\end{Arguments}
\begin{Value}
a Trellis plot of the estimated random-effects (coefficients) versus
covariates, or groups.
\end{Value}
\begin{Author}\relax
Jose Pinheiro \email{Jose.Pinheiro@pharma.novartis.com} and Douglas Bates \email{bates@stat.wisc.edu}
\end{Author}
\begin{SeeAlso}\relax
\code{\LinkA{lmList}{lmList}}, \code{\LinkA{dotplot}{dotplot}}
\end{SeeAlso}
\begin{Examples}
\begin{ExampleCode}
fm1 <- lmList(distance ~ age | Subject, Orthodont)
plot(ranef(fm1))
fm1RE <- ranef(fm1, aug = TRUE)
plot(fm1RE, form = ~ Sex)
## Not run: 
plot(fm1RE, form = age ~ Sex)
## End(Not run)
\end{ExampleCode}
\end{Examples}

