Dataset: leaves.csv

Description: Size of maple (Acer platanoides) leaves.

License: CC BY-SA 4.0 https://creativecommons.org/licenses/by-sa/4.0/

Source: The data are from a students course experiment in 2015:

Two groups of students had the task to measure width, length, 
 and stalk length of maple trees.
 
The leaves are from the same trees, but samplig strategy was different:

* Group "HYB" got randomly sampled leaves.
* Group "HSE" hat the freedom to select an individual leave of their choice.

Note also that "length" contains some outliers, because some measurements 
added the stalk length to the leave length.

Thomas Petzoldt, Technische Universitaet Dresden, 
Institute of Hydrobiology, Workgroup Limnology