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Tip revision: 4fe059206e698a4b7135d792f3d533b173ecfe77 authored by Adrian Baddeley on 16 May 2012, 12:44:15 UTC
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redwoodfull.Rd
\name{redwoodfull}
\alias{redwoodfull}
\alias{redwoodfull.extra}
\docType{data}
\title{
  California Redwoods Point Pattern (Entire Dataset)
}
\description{
  These data represent the locations of 195 seedlings and saplings 
  of California redwood trees in a square sampling region.  
  They were described and analysed by Strauss (1975).
  This is the ``\bold{full}'' dataset; most writers have
  analysed a subset extracted by Ripley (1977)
  which is available as \code{\link{redwood}}.
 
  Strauss (1975) divided the sampling region into two subregions I and II
  demarcated by a diagonal line across the region. The spatial pattern
  appears to be slightly regular in region I and strongly clustered in 
  region II.

  The dataset \code{redwoodfull} contains the full point pattern
  of 195 trees. 
  The auxiliary information about the subregions is contained in 
  \code{redwoodfull.extra}, which is a list with entries
  \tabular{ll}{
    \code{diag}\tab The coordinates of the diagonal boundary\cr
               \tab between regions I and II \cr
    \code{regionI} \tab Region I as a window object \cr
    \code{regionII} \tab Region II as a window object \cr
    \code{regionR} \tab Ripley's subrectangle (approximate) \cr
    \code{plot}    \tab Function to plot the full data and auxiliary markings
  }

  Ripley (1977) extracted a subset of these data, containing 62 points,
  lying within a square subregion which overlaps regions I and II.
  He rescaled the data to the unit square. 
  This has been re-analysed many times, and is the dataset usually known as
  ``the redwood data'' in the spatial statistics literature.
  The exact dataset used by Ripley is supplied in the \pkg{spatstat}
  library as \code{\link{redwood}}.
  There are some minor inconsistencies with
  \code{redwood} since it originates from a different digitisation.

  The approximate position of the square chosen by Ripley
  within the \code{redwoodfull} pattern
  is indicated by the window \code{redwoodfull.extra$regionR}.
} 
\format{
  The dataset \code{redwoodfull} is an object of class \code{"ppp"}
  representing the point pattern of tree locations.
  The window has been rescaled to the unit square.
  See \code{\link{ppp.object}} for details of the format of a
  point pattern object.

  The dataset \code{redwoodfull.extra} is a list with entries
  \tabular{ll}{
    \code{diag}\tab coordinates of endpoints of a line,\cr
               \tab in format \code{list(x=numeric(2),y=numeric(2))} \cr
    \code{regionI} \tab a window object \cr
    \code{regionII} \tab a window object \cr
    \code{regionR} \tab a window object \cr
    \code{plot}    \tab Function with no arguments
  }
}
\usage{data(redwoodfull)}
\examples{
       data(redwoodfull)
       plot(redwoodfull)
       redwoodfull.extra$plot()
       # extract the pattern in region II 
       redwoodII <- redwoodfull[, redwoodfull.extra$regionII]
}
\source{Strauss (1975). The plot of the data published by Strauss (1975)
  was scanned and digitised by Sandra Pereira, University of
  Western Australia, 2002.
}
\seealso{
  \code{\link{redwood}}
}
\references{
  Diggle, P.J. (1983)
  \emph{Statistical analysis of spatial point patterns}.
  Academic Press.

  Ripley, B.D. (1977)
  Modelling spatial patterns (with discussion).
  \emph{Journal of the Royal Statistical Society, Series B}
  \bold{39}, 172--212.

  Strauss, D.J. (1975)
  A model for clustering.
  \emph{Biometrika} \bold{63}, 467--475.
}
\keyword{datasets}
\keyword{spatial}
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