% File nlme/man/Earthquake.Rd
% Part of the nlme package for R
% Distributed under GPL 2 or later: see nlme/LICENCE.note

\name{Earthquake}
\alias{Earthquake}
\title{Earthquake Intensity}
\description{
    The \code{Earthquake} data frame has 182 rows and 5 columns.
}
\format{
    This data frame contains the following columns:
    \describe{
        \item{Quake}{
            an ordered factor with levels
            \code{20} < \code{16} < \code{14} < \code{10} < \code{3} <
            \code{8} < \code{23} < \code{22} < \code{6} < \code{13} <
            \code{7} < \code{21} < \code{18} < \code{15} < \code{4} <
            \code{12} < \code{19} < \code{5} < \code{9} < \code{1} <
            \code{2} < \code{17} < \code{11} indicating the earthquake
            on which the measurements were made.
        }
        \item{Richter}{
            a numeric vector giving the intensity of the earthquake on
            the Richter scale.
        }
        \item{distance}{
            the distance from the seismological measuring station to the
            epicenter of the earthquake (km).
        }
        \item{soil}{
            a factor with levels \code{0} and \code{1}
            giving the soil condition at the measuring station, either
            soil or rock.
        }
        \item{accel}{
            maximum horizontal acceleration observed (g).
        }
    }
}
\details{
    Measurements recorded at available seismometer locations for 23
    large earthquakes in western North America between 1940 and 1980.
    They were originally given in Joyner and Boore (1981); are
    mentioned in Brillinger (1987); and are analyzed in Davidian
    and Giltinan (1995).
}
\source{
    Pinheiro, J. C. and Bates, D. M. (2000), \emph{Mixed-Effects Models in S
        and S-PLUS}, Springer, New York.  (Appendix A.8)

    Davidian, M. and Giltinan, D. M. (1995), \emph{Nonlinear Models for
        Repeated Measurement Data},  Chapman and Hall, London.

    Joyner and Boore (1981), Peak horizontal acceleration and velocity from
    strong-motion records including records from the 1979 Imperial
    Valley, California, earthquake, \emph{Bulletin of the Seismological
        Society of America}, \bold{71}, 2011-2038.

    Brillinger, D. (1987), Comment on a paper by C. R. Rao,
    \emph{Statistical Science}, \bold{2}, 448-450.
}
%\examples{}
\keyword{datasets}