| % File src/library/datasets/man/Loblolly.Rd |
| % Part of the R package, https://www.R-project.org |
| % Copyright 1995-2011 R Core Team |
| % Distributed under GPL 2 or later |
| |
| \name{Loblolly} |
| \docType{data} |
| \alias{Loblolly} |
| \title{Growth of Loblolly pine trees} |
| \description{ |
| The \code{Loblolly} data frame has 84 rows and 3 columns of records of |
| the growth of Loblolly pine trees. |
| } |
| \usage{Loblolly} |
| \format{ |
| An object of class |
| \code{c("nfnGroupedData", "nfGroupedData", "groupedData", "data.frame")} |
| containing the following columns: |
| \describe{ |
| \item{height}{ |
| a numeric vector of tree heights (ft). |
| } |
| \item{age}{ |
| a numeric vector of tree ages (yr). |
| } |
| \item{Seed}{ |
| an ordered factor indicating the seed source for the tree. |
| The ordering is according to increasing maximum height. |
| } |
| } |
| } |
| \details{ |
| This dataset was originally part of package \code{nlme}, and that has |
| methods (including for \code{[}, \code{as.data.frame}, \code{plot} and |
| \code{print}) for its grouped-data classes. |
| } |
| \source{ |
| Kung, F. H. (1986), |
| Fitting logistic growth curve with predetermined carrying capacity, |
| in \emph{Proceedings of the Statistical Computing Section, |
| American Statistical Association}, 340--343. |
| |
| Pinheiro, J. C. and Bates, D. M. (2000) |
| \emph{Mixed-effects Models in S and S-PLUS}, Springer. |
| } |
| \examples{ |
| require(stats); require(graphics) |
| plot(height ~ age, data = Loblolly, subset = Seed == 329, |
| xlab = "Tree age (yr)", las = 1, |
| ylab = "Tree height (ft)", |
| main = "Loblolly data and fitted curve (Seed 329 only)") |
| fm1 <- nls(height ~ SSasymp(age, Asym, R0, lrc), |
| data = Loblolly, subset = Seed == 329) |
| age <- seq(0, 30, length.out = 101) |
| lines(age, predict(fm1, list(age = age))) |
| } |
| \keyword{datasets} |