size
| measured size (height times diameter squared) of tree, on log scale. |
Time
| time of measurement in days since 1 January 1988 |
tree
| number of tree |
treat
|
either "ozone" for an ozone-enriched chamber or "control"
|
Sitka89
data frame has 632 rows and 4 columns. It gives repeated
measurements on the log-size of 79 Sitka spruce trees, 54 of which
were grown in ozone-enriched chambers and 25 were controls. The size
was measured eight times in 1989, at roughly monthly intervals.Sitka