\Header{longley}{Longley's Regression Data}
\keyword{datasets}{longley}
\begin{Usage}
\begin{verbatim}data(longley)\end{verbatim}
\end{Usage}
\begin{Format}
A data frame with 7 economical variables, observed yearly
from 1947 to 1962 (\eqn{n=16}{}).

\Tabular{rl}{
GNP.deflator: & GNP implicit price deflator (\eqn{1954=100}{})\\{}
GNP:          & Gross National Producr.\\{}
Unemployed:   & number of unemployed \\{}
Armed.Forces: & number of .. in the armed forces\\{}
Population:   & `noninstitutionalized' population\\{}
& \eqn{\ge}{} 14 years of age.\\{} 
Year:         & the year (time).\\{}
Employed:     & number of people employed.
}

The regression \texttt{lm(Employed $\,\tilde{\,}$ .)} is known to be highly
collinear.\end{Format}
\begin{Source}
J. W. Longley (1967).
An appraisal of least-squares programs from the point of view of the
user.
\emph{Journal of the American Statistical Association} \bold{62},
819--841.\end{Source}
\begin{Examples}
\begin{ExampleCode}
# give the data set in the form it is used in S-plus:
data(longley)
longley.x <- data.matrix(longley[, 1:6])
longley.y <- longley[, "Employed"]
\end{ExampleCode}
\end{Examples}

