\name{ex15.15}
\alias{ex15.15}
\docType{data}
\title{data from exercise 15.15}
\description{
The \code{ex15.15} data frame has 15 rows and 2 columns.
}
\format{
This data frame contains the following columns:
\describe{
\item{conc}{
a numeric vector
}
\item{exposed}{
a factor with levels
\code{N} 
\code{Y} 
}
}
}
\details{
}
\source{
  Devore, J. L. (2003) \emph{Probability and Statistics for Engineering and the Sciences (6th ed)}, Duxbury
}
\examples{
data(ex15.15)
}
\keyword{datasets}