Description: Growth of Orange Trees

The Orange data frame has 35 rows and 3 columns of records of the growth of orange trees.

Variables

• Tree: an ordered factor indicating the tree on which the measurement is made. The ordering is according to increasing maximum diameter.
• age: a numeric vector giving the age of the tree (days since 1968/12/31)
• circumference: a numeric vector of trunk circumferences (mm). This is probably “circumference at breast height”, a standard measurement in forestry.

str(Orange)

## Classes 'nfnGroupedData', 'nfGroupedData', 'groupedData' and 'data.frame':   35 obs. of  3 variables:
##  $ Tree         : Ord.factor w/ 5 levels "3"<"1"<"5"<"2"<..: 2 2 2 2 2 2 2 4 4 4 ...
##  $ age          : num  118 484 664 1004 1231 ...
##  $ circumference: num  30 58 87 115 120 142 145 33 69 111 ...
##  - attr(*, "formula")=Class 'formula'  language circumference ~ age | Tree
##   .. ..- attr(*, ".Environment")=<environment: R_EmptyEnv> 
##  - attr(*, "labels")=List of 2
##   ..$ x: chr "Time since December 31, 1968"
##   ..$ y: chr "Trunk circumference"
##  - attr(*, "units")=List of 2
##   ..$ x: chr "(days)"
##   ..$ y: chr "(mm)"