Growth of Orange Trees

SUMMARY:

Data on five orange trees grown at Riverside, California. Measurements of the trunk circumference (in millimeters) were made on each of the trees at 7 different times. The times are given relative to the arbitrary origin of December 31, 1968.

DATA DESCRIPTION:

This data frame contains the following columns:

VALUE:

Tree
a factor indicating the tree on which the measurement is made.
age
the date of the measurement in days since December 31, 1968.
circumference
the circumference of the tree trunk (mm). This is probably the standard forestry measurement of trunk circumference at breast height.

SOURCE:

These data are quoted in Draper and Smith (1981), Applied Regression Analysis, Wiley, New York (chapter 10, exercise N, page 524).

SEE ALSO:

, , , .

EXAMPLES:

Orange.lis <- nlsList(circumference ~ logistic(age, Asym, T50, scal), 
    data = Orange, cluster = ~ Tree) 
Orange.nlme <- nlme(Orange.lis)