\Header{coop}{Co-operative Trial in Analytical Chemistry}
\keyword{datasets}{coop}
\begin{Description}\relax
Seven specimens were sent to 6 laboratories in 3 separate batches and
each analysed for Analyte.  Each analysis was duplicated.
\end{Description}
\begin{Usage}
\begin{verbatim}
data(coop)
\end{verbatim}
\end{Usage}
\begin{Format}\relax
This data frame contains the following columns:
\describe{
\item[\code{Lab}] Laboratory, \code{L1}, \code{L2}, \dots, \code{L6}.

\item[\code{Spc}] Specimen, \code{S1}, \code{S2}, \dots, \code{S6}.

\item[\code{Bat}] Batch, \code{B1}, \code{B2}, \code{B3} (nested within \code{Spc/Lab}),

\item[\code{Conc}] Concentration of Analyte in g/kg.
}
\end{Format}
\begin{Source}\relax
Analytical Methods Committee (1987)
Recommendations for the conduct and
interpretation of co-operative trials,
\emph{The Analyst}
\bold{112}, 679--686.
\end{Source}
\begin{References}\relax
Venables, W. N. and Ripley, B. D. (2002)
\emph{Modern Applied Statistics with S.} Fourth edition.  Springer.
\end{References}
\begin{SeeAlso}\relax
\code{\Link{chem}}, \code{\Link{abbey}}.
\end{SeeAlso}

