\name{FixedQNormalParam}
\alias{FixedQNormalParam}
\alias{getH}
\alias{getHvec}
\alias{getH<-}
\alias{getR}
\alias{getz}
\title{Parameter for the FixedQNormalPM
}
\description{

  The \code{\link{FixedQNormalEM}} is a proficiency model for a single
  time point where both the proficiency and observation are
  multidimensional.
  The parameter consists of a set of proficiency weights, \code{Hvec}, a
  mean vector, \code{z}, and a covariance matrix, \code{R}.

}
\usage{
FixedQNormalParam(...)
getHvec(param)
getH(param,Q)
getH(param,Q) <- value
getz(param)
getR(param)
}
%- maybe also 'usage' for other objects documented here.
\arguments{
  \item{\dots}{
    A list of values.  This should include \code{H} and \code{R}
    matrixes and a \code{z} vector.
  }
  \item{param}{
    A \code{FixedQNormalParam} object whose paramers are desired.
  }
  \item{value}{
    A new value for the indicated parameter.
  }
  \item{Q}{
    A Q-matrix.
  }
}
\details{

  This class is the parameter object corresponding to the
  \code{\link{FixedQNormalEM}} object.  The slot \code{z} contains
  the mean vector for the observables and the slot \code{R} contains the
  covariance matrix.

  The loadings for the proficiency variables are \code{H*Q}, where
  \code{H} is the matrix form of the loadings, and \code{Q} is a
  structural matrix provided by the evidence model.  As elements of
  \code{H} that correspond to zero element of \code{Q} have no impact on
  the distribution of the observable, \code{Hvec} is stored in a way
  that squeezes out these zero elements.  The functions \code{getH} and
  \code{getH<-} manipulate the loadings in the matrix form and the
  function \code{getHvec} works on compress vector.
  
}
\value{

  A \code{FixedQNormalParam} object with slots:
  \item{Hvec}{Loadings (as a vector with zeros removed).}
  \item{z}{Mean vector}
  \item{R}{Covariance matrix}.

  The functions \code{getmu} and \code{getSigma} return the value of the
  corresponding slots.
}
\references{
%% ~put references to the literature/web site here ~
}
\author{Russell Almond}

\seealso{
  Superclass:
  \code{\link{ParameterObject}}
  
  Subclasses:

  
  Used By:
  \code{\link{FixedQNormalEM}}
}
\examples{

Q <- matrix(c(1,0,1,1),2,2)
p1 <- new("FixedQNormalParam",
          Hvec = matrix(c(.7,.3,.3,.7),2,2)[abs(Q)>0],
          z=c(Mechanics=0,Fluencey=0),
          R=diag(c(.65,.65),2,2))

getHvec(p1)
getH(p1,Q)
getR(p1)
getz(p1)
pvec(p1)
diag(getH(p1,Q)) <- c(1,.9)
stopifnot(sum(abs(pvec(p1)[1:3]-c(1,.3,.9))) <.0001)

pvec(p1)[4]<-3
stopifnot (getz(p1)==c(3,0))

pvec(p1)[8] <- .25
stopifnot(abs(getR(p1)[lower.tri(getR(p1))]-.25) < .0001)

}
\keyword{ class }