swh:1:snp:dc80812a22a7696ce24055bd58afbf9f13e3e78c
Tip revision: c81639b9efbc365dff7f4e9cf6d6f5ff01210771 authored by Friedrich Leisch on 07 September 2007, 00:00:00 UTC
version 2.0-1
version 2.0-1
Tip revision: c81639b
dmft.Rd
\name{dmft}
\alias{dmft}
\docType{data}
\title{Dental data}
\description{
Count data from a dental epidemiological study for evaluation of
various programs for reducing caries collected among school
children from an urban area of Belo Horizonte (Brazil).
}
\usage{data("dmft")}
\format{
A data frame with 797 observations on the following 5 variables.
\describe{
\item{End}{Number of decayed, missing or filled teeth at the end of the study.}
\item{Begin}{Number of decayed, missing or filled teeth at the beginning of the study.}
\item{Gender}{A factor with levels \code{male} and \code{female}.}
\item{Ethnic}{A factor with levels \code{brown}, \code{white} and \code{black}.}
\item{Treatment}{A factor with levels \code{control}, \code{educ}, \code{enrich},
\code{rinse}, \code{hygiene} and \code{all}.}
}
}
\details{
The aim of the caries prevention study was to compare four methods
to prevent dental caries. Interventions were carried out according
to the following scheme:
\describe{
\item{control}{Control group}
\item{educ}{Oral health education}
\item{enrich}{Enrichment of the school diet with rice bran}
\item{rinse}{Mouthwash with 0.2\% sodium floride (NaF) solution}
\item{hygiene}{Oral hygiene}
\item{all}{All four methods together}
}
}
\source{
D. Boehning, E. Dietz, P. Schlattmann, L. Mendonca and U. Kirchner
(1999): The zero-inflated Poisson model and the decayed, missing and
filled teeth index in dental epidemiology. Journal of the Royal
Statistical Society A 162(2), pages 195-209.
}
\examples{
data("dmft")
dmft.flx <- stepFlexmix(End ~ 1, data = dmft, k = 2,
model = FLXMRglmfix(family = "poisson",
fixed = ~ Gender + Ethnic + Treatment))
}
\keyword{datasets}