The ChickWeight data frame has 578 rows and 4 columns from an
experiment on the effect of diet on early growth of chicks.
Usage
ChickWeight
Format
An object of class
c("nfnGroupedData", "nfGroupedData", "groupedData", "data.frame")
containing the following columns:
weight
a numeric vector giving the body weight of the chick (gm).
Time
a numeric vector giving the number of days since birth when
the measurement was made.
Chick
an ordered factor with levels
18 < ... < 48
giving a unique identifier for the chick. The ordering of
the levels groups chicks on the same diet together and
orders them according to their final weight (lightest to
heaviest) within diet.
Diet
a factor with levels 1, ..., 4 indicating which
experimental diet the chick received.
Details
The body weights of the chicks were measured at birth and every
second day thereafter until day 20. They were also measured on day
21. There were four groups on chicks on different protein diets.
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.
Source
Crowder, M. and Hand, D. (1990), Analysis of Repeated Measures,
Chapman and Hall (example 5.3)
Hand, D. and Crowder, M. (1996), Practical Longitudinal Data
Analysis, Chapman and Hall (table A.2)
Pinheiro, J. C. and Bates, D. M. (2000) Mixed-effects Models in
S and S-PLUS, Springer.
See Also
SSlogis for models fitted to this dataset.
Examples
require(graphics)
coplot(weight ~ Time | Chick, data = ChickWeight,
type = "b", show.given = FALSE)
Results
R version 3.3.1 (2016-06-21) -- "Bug in Your Hair"
Copyright (C) 2016 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)
R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.
R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.
Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.
> library(datasets)
> png(filename="/home/ddbj/snapshot/RGM3/R_rel/result/datasets/ChickWeight.Rd_%03d_medium.png", width=480, height=480)
> ### Name: ChickWeight
> ### Title: Weight versus age of chicks on different diets
> ### Aliases: ChickWeight
> ### Keywords: datasets
>
> ### ** Examples
> ## No test:
> require(graphics)
> coplot(weight ~ Time | Chick, data = ChickWeight,
+ type = "b", show.given = FALSE)
> ## End(No test)
>
>
>
>
> dev.off()
null device
1
>