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\name{cmm_init_vector_kmeans}
\alias{cmm_init_vector_kmeans}
\docType{methods}
\title{Estimate Cauchy Mixture parameters using Expectation Maximization.}
\description{
Estimate an initialization vector for Cauchy mixture fitting using k-means.
R implementation of k-means in kmeans() is used to find data point assignment to clusters.
Then several iterations of Cauchy mixture fitting (per Nahy 2006) is used to derive mixture parameters.
}
\usage{
cmm_init_vector_kmeans( x, m, iter.cauchy = 20 )
}
\arguments{
\item{x}{data vector}
\item{m}{number of mixture components}
\item{iter.cauchy}{number of iterations to fit a single Cauchy component.}
}
\value{
Parameter vector of 3*\emph{n} parameters, where \emph{n} is
number of mixture components. Structure of p vector is
p = c( A1, A2, ..., A\emph{n}, mu1, mu2, ..., mu\emph{n}, gamma1, gamma2, ..., gamma\emph{n} ),
where A\emph{i} is the proportion of \emph{i}-th component,
mu\emph{i} is the center of \emph{i}-th component and
gamma\emph{i} is the Cauchy scale of \emph{i}-th component.
}
\references{
Ferenc Nahy. Parameter Estimation of the Cauchy Distribution in
Information Theory Approach (2006).
Journal of Universal Computer Science
}
\author{Andrius Merkys}
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