\HeaderA{Oxide}{Variability in Semiconductor Manufacturing}{Oxide}
\keyword{datasets}{Oxide}
\begin{Description}\relax
The \code{Oxide} data frame has 72 rows and 5 columns.
\end{Description}
\begin{Format}\relax
This data frame contains the following columns:
\describe{
\item[Source] a factor with levels
\code{1} and
\code{2} 

\item[Lot] a factor giving a unique identifier for each lot.

\item[Wafer] a factor giving a unique identifier for each wafer within a lot.

\item[Site] a factor with levels
\code{1}, 
\code{2}, and 
\code{3} 

\item[Thickness] a numeric vector giving the thickness of the oxide layer.

}
\end{Format}
\begin{Details}\relax
These data are described in Littell et al. (1996, p. 155) as coming
``from a passive data collection study in the semiconductor industry
where the objective is to estimate the variance components to
determine the assignable causes of the observed variability.'' The
observed response is the thickness of the oxide layer on silicon
wafers, measured at three different sites of each of three wafers
selected from each of eight lots sampled from the population of
lots.
\end{Details}
\begin{Source}\relax
Pinheiro, J. C. and Bates, D. M. (2000), \emph{Mixed-Effects Models in S
and S-PLUS}, Springer, New York.  (Appendix A.20)

Littell, R. C., Milliken, G. A., Stroup, W. W. and Wolfinger,
R. D. (1996), \emph{SAS System for Mixed Models}, SAS Institute,
Cary, NC.
\end{Source}

