R/data-hgrdfir.r

In datana: Datasets and Functions to Accompany Analisis De Datos Con R

#' Tree height growth of Douglas-fir sample trees in the Northwest of
#' the United States
#' @description
#' Data contains 148 observations on the height growth of dominant trees of
#'  Pseudotsguga mensiezzi in the Northwest of the United States.
#' @usage
#' data(hgrdfir)
#' @format The data frame contains seven variables as follows:
#' \describe{
#'   \item{natfor.id}{Code identifier.}
#'   \item{plot.code}{Plot number identification}
#'   \item{tree.code}{Tree number identification.}
#'   \item{dbh}{Diameter at breast height at sampling, in in.}
#'   \item{toth}{Total height at sa,pling, in ft.}
#'   \item{age}{Age of tree, yr.}
#'   \item{height}{Height at a given age, in ft.}
#'  }
#' @source
#' The data were provided by Dr Christian Salas.
#' @references
#' - Monserud RA. 1984. Height growth and site index curves for Inland
#' Douglas-fir based on
#' stem analysis data and forest habitat type. Forest Science 30(4):943-965.
#' @references
#' - Salas C, Stage AR, and Robinson AP. 2008. Modeling effects of
#' overstory density and competing
#' vegetation on tree height growth. Forest Science 54(1):107-122.
#'  \doi{10.1093/forestscience/54.1.107}
#' @examples
#' data(hgrdfir)
#' head(hgrdfir)
#' unique(hgrdfir$tree.code)
#' table(hgrdfir$plot.code,hgrdfir$tree.code)
#' tapply(hgrdfir$dbh, hgrdfir$tree.code, mean)
#' tapply(hgrdfir$dbh, hgrdfir$tree.code, mean) #dbh of each sample tree
#' tapply(hgrdfir$toth, hgrdfir$tree.code, mean) #toth of each sample tree
"hgrdfir"