Loblolly
Growth of Loblolly pine trees
The Loblolly
data frame has 84 rows and 3 columns of records of
the growth of Loblolly pine trees.
- Keywords
- datasets
Usage
Loblolly
Details
This dataset was originally part of package nlme
, and that has
methods (including for [
, as.data.frame
, plot
and
print
) for its grouped-data classes.
Format
An object of class
c("nfnGroupedData", "nfGroupedData", "groupedData", "data.frame")
containing the following columns:
- height
- a numeric vector of tree heights (ft).
- age
- a numeric vector of tree ages (yr).
- Seed
- an ordered factor indicating the seed source for the tree. The ordering is according to increasing maximum height.
Source
Kung, F. H. (1986), Fitting logistic growth curve with predetermined carrying capacity, in Proceedings of the Statistical Computing Section, American Statistical Association, 340--343. Pinheiro, J. C. and Bates, D. M. (2000) Mixed-effects Models in S and S-PLUS, Springer.
Examples
library(datasets)
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)))
Community examples
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